1998
Swan, J. Shannon; Langlotz, C. P.
In: Invest Radiol, vol. 33, no. 9, pp. 553-9, 1998, ISSN: 0020-9996 (Print) 0020-9996 (Li, ().
@article{Swan1998,
title = {Patient preference for magnetic resonance versus conventional angiography. Assessment methods and implications for cost-effectiveness analysis: an overview},
author = {J. Shannon Swan and C. P. Langlotz},
url = {https://www.ncbi.nlm.nih.gov/pubmed/9766040},
doi = {10.1097/00004424-199809000-00011},
issn = {0020-9996 (Print)
0020-9996 (Li},
year = {1998},
date = {1998-01-01},
journal = {Invest Radiol},
volume = {33},
number = {9},
pages = {553-9},
keywords = {},
pubstate = {published},
tppubtype = {article}
}
Willig, D. S.; Turski, P. A.; Frayne, R.; Graves, V. B.; Korosec, F. R.; Swan, J. Shannon; Mistretta, C. A.; Grist, T. M.
In: Radiology, vol. 208, no. 2, pp. 447-51, 1998, ISSN: 0033-8419 (Print) 0033-8419 (Li, ().
@article{Willig1998,
title = {Contrast-enhanced 3D MR DSA of the carotid artery bifurcation: preliminary study of comparison with unenhanced 2D and 3D time-of-flight MR angiography},
author = {D. S. Willig and P. A. Turski and R. Frayne and V. B. Graves and F. R. Korosec and J. Shannon Swan and C. A. Mistretta and T. M. Grist},
url = {https://www.ncbi.nlm.nih.gov/pubmed/9680574},
doi = {10.1148/radiology.208.2.9680574},
issn = {0033-8419 (Print) 0033-8419 (Li},
year = {1998},
date = {1998-01-01},
urldate = {1998-01-01},
journal = {Radiology},
volume = {208},
number = {2},
pages = {447-51},
keywords = {},
pubstate = {published},
tppubtype = {article}
}
Westmoreland, S. V.; Halpern, Elkan F.; Lackner, A. A.
Simian immunodeficiency virus encephalitis in rhesus macaques is associated with rapid disease progression Journal Article
In: J Neurovirol, vol. 4, pp. 260-8, 1998, ().
@article{Westmoreland1998,
title = {Simian immunodeficiency virus encephalitis in rhesus macaques is
associated with rapid disease progression},
author = {S. V. Westmoreland and Elkan F. Halpern and A. A. Lackner},
url = {http://www.ncbi.nlm.nih.gov/pubmed/9639069},
year = {1998},
date = {1998-01-01},
journal = {J Neurovirol},
volume = {4},
pages = {260-8},
abstract = {Central nervous system (CNS) disease is a major feature of simian
immunodeficiency virus (SIV) infection of macaques. To define the
spectrum of CNS lesions in SIV-infected macaques and the potential
associations with viral strain and disease course, we performed a
retrospective analysis of necropsies on 124 macaques with SIV-induced
AIDS. Histologic evidence of CNS disease was observed in 71 (57.3
of the 124 animals. SIV encephalitis was the most common CNS lesion
occurring in 43.7% (31/71) of the animals with CNS disease and 25%
of all animals. The incidence of SIVE correlated significantly with shortened survival (P=0.0207). In addition, SIVE was seen in 42.9%
(15/35) of rapid progressors (animals that died within 200 days)
compared to only 18% (16/89) of normal progressors (animals that lived longer than 200 days) (P=0.011). Animals with SIVE had higher
viral loads in peripheral blood than those that did not, but this
difference did not reach statistical significance. Similarly, while
animals infected with uncloned SIVmac251 had a higher incidence of
SIVE (27.5 14/51) than animals infected with molecularly cloned SIVmac239
and its T-cell tropic derivatives (18.5 10/54) this difference was
not statistically significant. In this study rapid disease progression
and SIVE were highly correlated making separation of viral determinants
of virulence from those of neurovirulence difficult.},
keywords = {},
pubstate = {published},
tppubtype = {article}
}
Central nervous system (CNS) disease is a major feature of simian
immunodeficiency virus (SIV) infection of macaques. To define the
spectrum of CNS lesions in SIV-infected macaques and the potential
associations with viral strain and disease course, we performed a
retrospective analysis of necropsies on 124 macaques with SIV-induced
AIDS. Histologic evidence of CNS disease was observed in 71 (57.3
of the 124 animals. SIV encephalitis was the most common CNS lesion
occurring in 43.7% (31/71) of the animals with CNS disease and 25%
of all animals. The incidence of SIVE correlated significantly with shortened survival (P=0.0207). In addition, SIVE was seen in 42.9%
(15/35) of rapid progressors (animals that died within 200 days)
compared to only 18% (16/89) of normal progressors (animals that lived longer than 200 days) (P=0.011). Animals with SIVE had higher
viral loads in peripheral blood than those that did not, but this
difference did not reach statistical significance. Similarly, while
animals infected with uncloned SIVmac251 had a higher incidence of
SIVE (27.5 14/51) than animals infected with molecularly cloned SIVmac239
and its T-cell tropic derivatives (18.5 10/54) this difference was
not statistically significant. In this study rapid disease progression
and SIVE were highly correlated making separation of viral determinants
of virulence from those of neurovirulence difficult.
immunodeficiency virus (SIV) infection of macaques. To define the
spectrum of CNS lesions in SIV-infected macaques and the potential
associations with viral strain and disease course, we performed a
retrospective analysis of necropsies on 124 macaques with SIV-induced
AIDS. Histologic evidence of CNS disease was observed in 71 (57.3
of the 124 animals. SIV encephalitis was the most common CNS lesion
occurring in 43.7% (31/71) of the animals with CNS disease and 25%
of all animals. The incidence of SIVE correlated significantly with shortened survival (P=0.0207). In addition, SIVE was seen in 42.9%
(15/35) of rapid progressors (animals that died within 200 days)
compared to only 18% (16/89) of normal progressors (animals that lived longer than 200 days) (P=0.011). Animals with SIVE had higher
viral loads in peripheral blood than those that did not, but this
difference did not reach statistical significance. Similarly, while
animals infected with uncloned SIVmac251 had a higher incidence of
SIVE (27.5 14/51) than animals infected with molecularly cloned SIVmac239
and its T-cell tropic derivatives (18.5 10/54) this difference was
not statistically significant. In this study rapid disease progression
and SIVE were highly correlated making separation of viral determinants
of virulence from those of neurovirulence difficult.
Kong, Chung Yin; Muthukumar, M.
Monte Carlo Study of Adsorption of a Polyelectrolyte onto Charged Surfaces Journal Article
In: J. Chemical Physics, vol. 109, pp. 1522, 1998, ().
@article{Kong1998,
title = {Monte Carlo Study of Adsorption of a Polyelectrolyte onto Charged Surfaces},
author = {Chung Yin Kong and M. Muthukumar},
url = {http://scitation.aip.org/content/aip/journal/jcp/109/4/10.1063/1.476703},
year = {1998},
date = {1998-01-01},
journal = {J. Chemical Physics},
volume = {109},
pages = {1522},
keywords = {},
pubstate = {published},
tppubtype = {article}
}
Goldberg, S. N.; Gazelle, G. Scott; Solbiati, L.; Livraghi, T.; Tanabe, K. K.; Hahn, P. F.; Mueller, P. R.
Ablation of liver tumors using percutaneous RF therapy Journal Article
In: AJR Am J Roentgenol, vol. 170, pp. 1023-8, 1998, ().
@article{Goldberg1998,
title = {Ablation of liver tumors using percutaneous RF therapy},
author = {S. N. Goldberg and G. Scott Gazelle and L. Solbiati and T. Livraghi and K. K. Tanabe and P. F. Hahn and P. R. Mueller},
url = {http://www.ncbi.nlm.nih.gov/pubmed/9530053},
year = {1998},
date = {1998-01-01},
urldate = {1998-01-01},
journal = {AJR Am J Roentgenol},
volume = {170},
pages = {1023-8},
keywords = {},
pubstate = {published},
tppubtype = {article}
}
Goldberg, S. N.; Hahn, P. F.; McGovern, F. J.; Fogle, R. M.; Mueller, P. R.; Gazelle, G. Scott
Benign prostatic hyperplasia: US-guided transrectal urethral enlargement with radio frequency--initial results in a canine model Journal Article
In: Radiology, vol. 208, pp. 491-8, 1998, ().
@article{Goldberg1998c,
title = {Benign prostatic hyperplasia: US-guided transrectal urethral enlargement
with radio frequency--initial results in a canine model},
author = {S. N. Goldberg and P. F. Hahn and F. J. McGovern and R. M. Fogle and P. R. Mueller and G. Scott Gazelle},
url = {http://www.ncbi.nlm.nih.gov/pubmed/9680581},
year = {1998},
date = {1998-01-01},
journal = {Radiology},
volume = {208},
pages = {491-8},
abstract = {PURPOSE: To enlarge the prostatic urethra with thermal coagulation
with transrectal radio-frequency (RF) application in dogs. MATERIALS
AND METHODS: Eight aged dogs underwent RF ablation of periurethral
prostatic tissue for 6 minutes. Eighteen-gauge electrodes were placed
into the periurethral tissues with a transrectal approach and ultrasound
(US) guidance. Prostatic and rectal temperatures were measured during
RF application. US, conventional and computed tomographic (CT) retrograde urethrography (RUG), and CT were performed immediately (n = 8) and at 3-96 days (n = 6) after ablation. Histopathologic analysis was performed at sacrifice immediately (n = 2), at 28 days (n = 2), or at 3 months (n = 4) after treatment. RESULTS: All procedures were
successful with no complications and were performed in less than
30 minutes. Rectal mucosal temperature did not exceed 38 degrees
C. Immediately after treatment, CT and US demonstrated 1.2-cm foci
of altered periurethral tissue that corresponded to solid coagulated
tissue at histopathologic analysis. By day 3, CT, RUG, and US demonstrated
that these foci had begun to cavitate, resulting in enlargement of
the urethra. Complete cavitation was demonstrated by day 28. Minimal
reduction in the degree of urethral enlargement was noted by day
60, but narrowing, urethral strictures, or fistulas were not observed
at 3 months. At histopathologic analysis, focal cavitary enlargement
with at least doubling of the urethral diameter and with normal urothelium
was noted in all dogs surviving at least 28 days. CONCLUSION: Transrectal
RF urethral enlargement is feasible and safe in animals and merits
investigation for alleviating urethral obstruction due to benign
prostatic hyperplasia.},
keywords = {},
pubstate = {published},
tppubtype = {article}
}
PURPOSE: To enlarge the prostatic urethra with thermal coagulation
with transrectal radio-frequency (RF) application in dogs. MATERIALS
AND METHODS: Eight aged dogs underwent RF ablation of periurethral
prostatic tissue for 6 minutes. Eighteen-gauge electrodes were placed
into the periurethral tissues with a transrectal approach and ultrasound
(US) guidance. Prostatic and rectal temperatures were measured during
RF application. US, conventional and computed tomographic (CT) retrograde urethrography (RUG), and CT were performed immediately (n = 8) and at 3-96 days (n = 6) after ablation. Histopathologic analysis was performed at sacrifice immediately (n = 2), at 28 days (n = 2), or at 3 months (n = 4) after treatment. RESULTS: All procedures were
successful with no complications and were performed in less than
30 minutes. Rectal mucosal temperature did not exceed 38 degrees
C. Immediately after treatment, CT and US demonstrated 1.2-cm foci
of altered periurethral tissue that corresponded to solid coagulated
tissue at histopathologic analysis. By day 3, CT, RUG, and US demonstrated
that these foci had begun to cavitate, resulting in enlargement of
the urethra. Complete cavitation was demonstrated by day 28. Minimal
reduction in the degree of urethral enlargement was noted by day
60, but narrowing, urethral strictures, or fistulas were not observed
at 3 months. At histopathologic analysis, focal cavitary enlargement
with at least doubling of the urethral diameter and with normal urothelium
was noted in all dogs surviving at least 28 days. CONCLUSION: Transrectal
RF urethral enlargement is feasible and safe in animals and merits
investigation for alleviating urethral obstruction due to benign
prostatic hyperplasia.
with transrectal radio-frequency (RF) application in dogs. MATERIALS
AND METHODS: Eight aged dogs underwent RF ablation of periurethral
prostatic tissue for 6 minutes. Eighteen-gauge electrodes were placed
into the periurethral tissues with a transrectal approach and ultrasound
(US) guidance. Prostatic and rectal temperatures were measured during
RF application. US, conventional and computed tomographic (CT) retrograde urethrography (RUG), and CT were performed immediately (n = 8) and at 3-96 days (n = 6) after ablation. Histopathologic analysis was performed at sacrifice immediately (n = 2), at 28 days (n = 2), or at 3 months (n = 4) after treatment. RESULTS: All procedures were
successful with no complications and were performed in less than
30 minutes. Rectal mucosal temperature did not exceed 38 degrees
C. Immediately after treatment, CT and US demonstrated 1.2-cm foci
of altered periurethral tissue that corresponded to solid coagulated
tissue at histopathologic analysis. By day 3, CT, RUG, and US demonstrated
that these foci had begun to cavitate, resulting in enlargement of
the urethra. Complete cavitation was demonstrated by day 28. Minimal
reduction in the degree of urethral enlargement was noted by day
60, but narrowing, urethral strictures, or fistulas were not observed
at 3 months. At histopathologic analysis, focal cavitary enlargement
with at least doubling of the urethral diameter and with normal urothelium
was noted in all dogs surviving at least 28 days. CONCLUSION: Transrectal
RF urethral enlargement is feasible and safe in animals and merits
investigation for alleviating urethral obstruction due to benign
prostatic hyperplasia.
Goldberg, S. N.; Hahn, P. F.; Tanabe, K. K.; Mueller, P. R.; Schima, W.; Athanasoulis, C. A.; Compton, C. C.; Solbiati, L.; Gazelle, G. Scott
Percutaneous radiofrequency tissue ablation: does perfusion-mediated tissue cooling limit coagulation necrosis? Journal Article
In: J Vasc Interv Radiol, vol. 9, pp. 101-11, 1998, ().
@article{Goldberg1998b,
title = {Percutaneous radiofrequency tissue ablation: does perfusion-mediated
tissue cooling limit coagulation necrosis?},
author = {S. N. Goldberg and P. F. Hahn and K. K. Tanabe and P. R. Mueller and W. Schima and C. A. Athanasoulis and C. C. Compton and L. Solbiati and G. Scott Gazelle},
url = {http://www.ncbi.nlm.nih.gov/pubmed/9468403},
year = {1998},
date = {1998-01-01},
journal = {J Vasc Interv Radiol},
volume = {9},
pages = {101-11},
abstract = {PURPOSE: To determine, by decreasing hepatic perfusion during radiofrequency
(RF) ablation, whether perfusion-mediated tissue cooling can explain
the reduced coagulation observed in in vivo studies compared to that
seen with RF application in ex vivo tissue. MATERIALS AND METHODS:
RF was applied in vivo with use of cooled-tip electrodes to normal porcine liver without (n = 8) and with balloon occlusion of the portal vein (n = 8), celiac artery (n = 3), or hepatic artery (n = 2), and to ex vivo calf liver (n = 10). In vivo trials of vasopressin (0.3-0.6 U/min) infusion during RF application with (n = 10) and without (n = 2) arterial balloon occlusion were also performed. Intraoperative
RF was subsequently performed in seven patients with hepatic colorectal
metastases with and without portal inflow occlusion. Remote thermometry
was performed in four patients. RESULTS: RF application (12 minutes)
during portal venous occlusion produced larger areas of coagulation
necrosis than RF with unaltered blood flow (2.9 cm +/- 0.1 vs 2.4
cm +/- 0.2 diameter; P textless .01). With celiac and hepatic artery
occlusion, coagulation diameter measured 2.7 cm +/- 0.2 and 2.5 cm
+/- 0.1, respectively. Infusion of vasopressin without vascular occlusion
reduced coagulation diameter to 1.1 cm. However, different methods
of hepatic or celiac arterial balloon occlusion with simultaneous
vasopressin infusion produced a mean 3.4 cm +/- 0.2 of necrosis.
Coagulation in ex vivo liver was 2.9 cm +/- 0.1 in diameter. Clinical
studies demonstrated greater coagulation diameter for metastases
treated during portal inflow occlusion (4.0 cm +/- 1.3) than for
tumors treated with normal blood flow (2.5 cm +/- 0.8; P textless
.05). Thermometry documented a 10 degrees C increase compared to
baseline at 10 mm and 20 mm from the electrode after 5 minutes of
portal inflow occlusion during constant RF application. CONCLUSIONS:
Perfusion-mediated tissue cooling reduces coagulation necrosis achievable
with RF ablation. Reduction of blood flow during RF application increases
coagulation in both an animal model and human liver metastases.},
keywords = {},
pubstate = {published},
tppubtype = {article}
}
PURPOSE: To determine, by decreasing hepatic perfusion during radiofrequency
(RF) ablation, whether perfusion-mediated tissue cooling can explain
the reduced coagulation observed in in vivo studies compared to that
seen with RF application in ex vivo tissue. MATERIALS AND METHODS:
RF was applied in vivo with use of cooled-tip electrodes to normal porcine liver without (n = 8) and with balloon occlusion of the portal vein (n = 8), celiac artery (n = 3), or hepatic artery (n = 2), and to ex vivo calf liver (n = 10). In vivo trials of vasopressin (0.3-0.6 U/min) infusion during RF application with (n = 10) and without (n = 2) arterial balloon occlusion were also performed. Intraoperative
RF was subsequently performed in seven patients with hepatic colorectal
metastases with and without portal inflow occlusion. Remote thermometry
was performed in four patients. RESULTS: RF application (12 minutes)
during portal venous occlusion produced larger areas of coagulation
necrosis than RF with unaltered blood flow (2.9 cm +/- 0.1 vs 2.4
cm +/- 0.2 diameter; P textless .01). With celiac and hepatic artery
occlusion, coagulation diameter measured 2.7 cm +/- 0.2 and 2.5 cm
+/- 0.1, respectively. Infusion of vasopressin without vascular occlusion
reduced coagulation diameter to 1.1 cm. However, different methods
of hepatic or celiac arterial balloon occlusion with simultaneous
vasopressin infusion produced a mean 3.4 cm +/- 0.2 of necrosis.
Coagulation in ex vivo liver was 2.9 cm +/- 0.1 in diameter. Clinical
studies demonstrated greater coagulation diameter for metastases
treated during portal inflow occlusion (4.0 cm +/- 1.3) than for
tumors treated with normal blood flow (2.5 cm +/- 0.8; P textless
.05). Thermometry documented a 10 degrees C increase compared to
baseline at 10 mm and 20 mm from the electrode after 5 minutes of
portal inflow occlusion during constant RF application. CONCLUSIONS:
Perfusion-mediated tissue cooling reduces coagulation necrosis achievable
with RF ablation. Reduction of blood flow during RF application increases
coagulation in both an animal model and human liver metastases.
(RF) ablation, whether perfusion-mediated tissue cooling can explain
the reduced coagulation observed in in vivo studies compared to that
seen with RF application in ex vivo tissue. MATERIALS AND METHODS:
RF was applied in vivo with use of cooled-tip electrodes to normal porcine liver without (n = 8) and with balloon occlusion of the portal vein (n = 8), celiac artery (n = 3), or hepatic artery (n = 2), and to ex vivo calf liver (n = 10). In vivo trials of vasopressin (0.3-0.6 U/min) infusion during RF application with (n = 10) and without (n = 2) arterial balloon occlusion were also performed. Intraoperative
RF was subsequently performed in seven patients with hepatic colorectal
metastases with and without portal inflow occlusion. Remote thermometry
was performed in four patients. RESULTS: RF application (12 minutes)
during portal venous occlusion produced larger areas of coagulation
necrosis than RF with unaltered blood flow (2.9 cm +/- 0.1 vs 2.4
cm +/- 0.2 diameter; P textless .01). With celiac and hepatic artery
occlusion, coagulation diameter measured 2.7 cm +/- 0.2 and 2.5 cm
+/- 0.1, respectively. Infusion of vasopressin without vascular occlusion
reduced coagulation diameter to 1.1 cm. However, different methods
of hepatic or celiac arterial balloon occlusion with simultaneous
vasopressin infusion produced a mean 3.4 cm +/- 0.2 of necrosis.
Coagulation in ex vivo liver was 2.9 cm +/- 0.1 in diameter. Clinical
studies demonstrated greater coagulation diameter for metastases
treated during portal inflow occlusion (4.0 cm +/- 1.3) than for
tumors treated with normal blood flow (2.5 cm +/- 0.8; P textless
.05). Thermometry documented a 10 degrees C increase compared to
baseline at 10 mm and 20 mm from the electrode after 5 minutes of
portal inflow occlusion during constant RF application. CONCLUSIONS:
Perfusion-mediated tissue cooling reduces coagulation necrosis achievable
with RF ablation. Reduction of blood flow during RF application increases
coagulation in both an animal model and human liver metastases.
Goldberg, S. N.; Solbiati, L.; Hahn, P. F.; Cosman, E.; Conrad, J. E.; Fogle, R.; Gazelle, G. Scott
In: Radiology, vol. 209, pp. 371-9, 1998, ().
@article{Goldberg1998a,
title = {Large-volume tissue ablation with radio frequency by using a clustered,
internally cooled electrode technique: laboratory and clinical experience
in liver metastases},
author = {S. N. Goldberg and L. Solbiati and P. F. Hahn and E. Cosman and J. E. Conrad and R. Fogle and G. Scott Gazelle},
url = {http://www.ncbi.nlm.nih.gov/pubmed/9807561},
year = {1998},
date = {1998-01-01},
journal = {Radiology},
volume = {209},
pages = {371-9},
abstract = {PURPOSE: To evaluate whether coagulation necrosis achievable with
radio-frequency (RF) ablation can be increased by using a cluster
of closely spaced electrodes. MATERIALS AND METHODS: RF was applied to ex vivo liver (n = 68), in vivo liver (n = 12), and in vivo muscle (n = 15) by using a cluster array of three separate internally cooled
electrodes spaced 0.5 cm apart. The diameter of coagulation necrosis
achieved with optimal RF deposition (1,400-2,150 peak mA) for 5-60
minutes of RF application was determined for electrode tip lengths
of 1.5-3.0 cm and compared with that obtained by using a single electrode
and otherwise similar technique. Ten patients with solitary intrahepatic
colorectal metastases were also treated by using cluster electrode
RF ablation. RESULTS: In ex vivo liver, simultaneous RF application
to electrode clusters for 15, 30, and 45 minutes produced 4.7 cm
+/- 0.1, 6.2 cm +/- 0.1, and 7.0 cm +/- 0.2 of coagulation necrosis,
respectively. In in vivo liver and muscle, RF applied to electrode
clusters for 12 minutes yielded 3.1 cm +/- 0.2 and 7.6 cm +/- 0.4
of coagulation, respectively. RF application to a single electrode
produced maximal coagulation of 2.9 cm in ex vivo liver, 1.8 cm in
in vivo liver, and 4.3 cm in muscle (P textless .01, all tissues).
In colorectal metastases, a single 12-15-minute application of RF
to an electrode cluster induced 4.5-7.0 cm of coagulation necrosis.
CONCLUSION: Simultaneous RF application to a cluster of three closely
spaced internally cooled electrodes enables a larger volume of coagulation
in ex vivo liver, in vivo tissues, and hepatic colorectal metastases
than previously reported.},
keywords = {},
pubstate = {published},
tppubtype = {article}
}
PURPOSE: To evaluate whether coagulation necrosis achievable with
radio-frequency (RF) ablation can be increased by using a cluster
of closely spaced electrodes. MATERIALS AND METHODS: RF was applied to ex vivo liver (n = 68), in vivo liver (n = 12), and in vivo muscle (n = 15) by using a cluster array of three separate internally cooled
electrodes spaced 0.5 cm apart. The diameter of coagulation necrosis
achieved with optimal RF deposition (1,400-2,150 peak mA) for 5-60
minutes of RF application was determined for electrode tip lengths
of 1.5-3.0 cm and compared with that obtained by using a single electrode
and otherwise similar technique. Ten patients with solitary intrahepatic
colorectal metastases were also treated by using cluster electrode
RF ablation. RESULTS: In ex vivo liver, simultaneous RF application
to electrode clusters for 15, 30, and 45 minutes produced 4.7 cm
+/- 0.1, 6.2 cm +/- 0.1, and 7.0 cm +/- 0.2 of coagulation necrosis,
respectively. In in vivo liver and muscle, RF applied to electrode
clusters for 12 minutes yielded 3.1 cm +/- 0.2 and 7.6 cm +/- 0.4
of coagulation, respectively. RF application to a single electrode
produced maximal coagulation of 2.9 cm in ex vivo liver, 1.8 cm in
in vivo liver, and 4.3 cm in muscle (P textless .01, all tissues).
In colorectal metastases, a single 12-15-minute application of RF
to an electrode cluster induced 4.5-7.0 cm of coagulation necrosis.
CONCLUSION: Simultaneous RF application to a cluster of three closely
spaced internally cooled electrodes enables a larger volume of coagulation
in ex vivo liver, in vivo tissues, and hepatic colorectal metastases
than previously reported.
radio-frequency (RF) ablation can be increased by using a cluster
of closely spaced electrodes. MATERIALS AND METHODS: RF was applied to ex vivo liver (n = 68), in vivo liver (n = 12), and in vivo muscle (n = 15) by using a cluster array of three separate internally cooled
electrodes spaced 0.5 cm apart. The diameter of coagulation necrosis
achieved with optimal RF deposition (1,400-2,150 peak mA) for 5-60
minutes of RF application was determined for electrode tip lengths
of 1.5-3.0 cm and compared with that obtained by using a single electrode
and otherwise similar technique. Ten patients with solitary intrahepatic
colorectal metastases were also treated by using cluster electrode
RF ablation. RESULTS: In ex vivo liver, simultaneous RF application
to electrode clusters for 15, 30, and 45 minutes produced 4.7 cm
+/- 0.1, 6.2 cm +/- 0.1, and 7.0 cm +/- 0.2 of coagulation necrosis,
respectively. In in vivo liver and muscle, RF applied to electrode
clusters for 12 minutes yielded 3.1 cm +/- 0.2 and 7.6 cm +/- 0.4
of coagulation, respectively. RF application to a single electrode
produced maximal coagulation of 2.9 cm in ex vivo liver, 1.8 cm in
in vivo liver, and 4.3 cm in muscle (P textless .01, all tissues).
In colorectal metastases, a single 12-15-minute application of RF
to an electrode cluster induced 4.5-7.0 cm of coagulation necrosis.
CONCLUSION: Simultaneous RF application to a cluster of three closely
spaced internally cooled electrodes enables a larger volume of coagulation
in ex vivo liver, in vivo tissues, and hepatic colorectal metastases
than previously reported.
Boland, G. W.; Lee, M. J.; Gazelle, G. Scott; Halpern, Elkan F.; McNicholas, M. M.; Mueller, P. R.
Characterization of adrenal masses using unenhanced CT: an analysis of the CT literature Journal Article
In: AJR Am J Roentgenol, vol. 171, pp. 201-4, 1998, ().
@article{Boland1998,
title = {Characterization of adrenal masses using unenhanced CT: an analysis
of the CT literature},
author = {G. W. Boland and M. J. Lee and G. Scott Gazelle and Elkan F. Halpern and M. M. McNicholas and P. R. Mueller},
url = {http://www.ncbi.nlm.nih.gov/pubmed/9648789},
year = {1998},
date = {1998-01-01},
journal = {AJR Am J Roentgenol},
volume = {171},
pages = {201-4},
abstract = {OBJECTIVE: Unenhanced CT scanning can reliably characterize incidentally
detected adrenal masses when observers use density measurements of
the adrenal gland. However, controversy exists as to the optimal
density threshold required to differentiate benign from malignant
lesions. This study attempts to establish a consensus by performing
a pooled analysis of data found in the CT literature. MATERIALS AND
METHODS: Ten CT reports were analyzed, from which individual adrenal
lesion density measurements were obtained for 495 adrenal lesions
(272 benign lesions and 223 malignant lesions). Threshold analysis
generated a range of sensitivities and specificities for lesion characterization
at different density thresholds. RESULTS: Sensitivity for characterizing
a lesion as benign ranged from 47% at a threshold of 2 H to 88% at
a threshold of 20 H. Similarly, specificity varied from 100% at a
threshold of 2 H to 84% at a threshold of 20 H. CONCLUSION: The attempt
to be absolutely certain that an adrenal lesion is benign may lead
to an unacceptably low sensitivity for lesion characterization. The
threshold chosen will depend on the patient population and the cost-benefit
approach to patient care.},
keywords = {},
pubstate = {published},
tppubtype = {article}
}
OBJECTIVE: Unenhanced CT scanning can reliably characterize incidentally
detected adrenal masses when observers use density measurements of
the adrenal gland. However, controversy exists as to the optimal
density threshold required to differentiate benign from malignant
lesions. This study attempts to establish a consensus by performing
a pooled analysis of data found in the CT literature. MATERIALS AND
METHODS: Ten CT reports were analyzed, from which individual adrenal
lesion density measurements were obtained for 495 adrenal lesions
(272 benign lesions and 223 malignant lesions). Threshold analysis
generated a range of sensitivities and specificities for lesion characterization
at different density thresholds. RESULTS: Sensitivity for characterizing
a lesion as benign ranged from 47% at a threshold of 2 H to 88% at
a threshold of 20 H. Similarly, specificity varied from 100% at a
threshold of 2 H to 84% at a threshold of 20 H. CONCLUSION: The attempt
to be absolutely certain that an adrenal lesion is benign may lead
to an unacceptably low sensitivity for lesion characterization. The
threshold chosen will depend on the patient population and the cost-benefit
approach to patient care.
detected adrenal masses when observers use density measurements of
the adrenal gland. However, controversy exists as to the optimal
density threshold required to differentiate benign from malignant
lesions. This study attempts to establish a consensus by performing
a pooled analysis of data found in the CT literature. MATERIALS AND
METHODS: Ten CT reports were analyzed, from which individual adrenal
lesion density measurements were obtained for 495 adrenal lesions
(272 benign lesions and 223 malignant lesions). Threshold analysis
generated a range of sensitivities and specificities for lesion characterization
at different density thresholds. RESULTS: Sensitivity for characterizing
a lesion as benign ranged from 47% at a threshold of 2 H to 88% at
a threshold of 20 H. Similarly, specificity varied from 100% at a
threshold of 2 H to 84% at a threshold of 20 H. CONCLUSION: The attempt
to be absolutely certain that an adrenal lesion is benign may lead
to an unacceptably low sensitivity for lesion characterization. The
threshold chosen will depend on the patient population and the cost-benefit
approach to patient care.
Lewin, J. S.; Connell, C. F.; Duerk, J. L.; Chung, Y. C.; Clampitt, M. E.; Spisak, J.; Gazelle, G. Scott; Haaga, J. R.
Interactive MRI-guided radiofrequency interstitial thermal ablation of abdominal tumors: clinical trial for evaluation of safety and feasibility Journal Article
In: J Magn Reson Imaging, vol. 8, no. 1, pp. 40-7, 1998, ISSN: 1053-1807 (Print) 1053-1807 (Lin, ().
@article{Lewin1998,
title = {Interactive MRI-guided radiofrequency interstitial thermal ablation of abdominal tumors: clinical trial for evaluation of safety and feasibility},
author = {J. S. Lewin and C. F. Connell and J. L. Duerk and Y. C. Chung and M. E. Clampitt and J. Spisak and G. Scott Gazelle and J. R. Haaga},
url = {http://www.ncbi.nlm.nih.gov/pubmed/9500259},
issn = {1053-1807 (Print) 1053-1807 (Lin},
year = {1998},
date = {1998-00-01},
urldate = {1998-00-01},
journal = {J Magn Reson Imaging},
volume = {8},
number = {1},
pages = {40-7},
abstract = {This clinical trial was performed to evaluate the safety and feasibility
of interactive MR-guided radiofrequency (RF) interstitial thermal
ablation (ITA) performed entirely within the MR imager. RF-ITA was
performed on 11 intra-abdominal metastatic tumors during 13 sessions.
The RF electrode was placed under MR guidance on a .2-T system using
rapid fast imaging with steady state precession (FISP) and true FISP
images. A custom 17-gauge electrode was used and was modified in
four sessions to allow circulation of iced saline for cooling during
ablation. Tissue necrosis monitoring and electrode repositioning
were based on rapid T2-weighted and short-inversion-time inversion
recovery (STIR) sequences. Morbidity and toxicity were assessed by
clinical and imaging criteria. The region of tissue destruction was
visible in all 11 tumors treated, as confirmed on subsequent contrast-enhanced
images. No significant morbidity was noted, and patient discomfort
was minimal. In conclusion, interactive MR-guided RF-ITA is feasible
on a clinical .2-T C-arm system with supplemental interventional
accessories with only minor patient morbidity. The ability to completely
ablate tumors with RF-ITA depends on tumor size and vascularity.},
keywords = {},
pubstate = {published},
tppubtype = {article}
}
This clinical trial was performed to evaluate the safety and feasibility
of interactive MR-guided radiofrequency (RF) interstitial thermal
ablation (ITA) performed entirely within the MR imager. RF-ITA was
performed on 11 intra-abdominal metastatic tumors during 13 sessions.
The RF electrode was placed under MR guidance on a .2-T system using
rapid fast imaging with steady state precession (FISP) and true FISP
images. A custom 17-gauge electrode was used and was modified in
four sessions to allow circulation of iced saline for cooling during
ablation. Tissue necrosis monitoring and electrode repositioning
were based on rapid T2-weighted and short-inversion-time inversion
recovery (STIR) sequences. Morbidity and toxicity were assessed by
clinical and imaging criteria. The region of tissue destruction was
visible in all 11 tumors treated, as confirmed on subsequent contrast-enhanced
images. No significant morbidity was noted, and patient discomfort
was minimal. In conclusion, interactive MR-guided RF-ITA is feasible
on a clinical .2-T C-arm system with supplemental interventional
accessories with only minor patient morbidity. The ability to completely
ablate tumors with RF-ITA depends on tumor size and vascularity.
of interactive MR-guided radiofrequency (RF) interstitial thermal
ablation (ITA) performed entirely within the MR imager. RF-ITA was
performed on 11 intra-abdominal metastatic tumors during 13 sessions.
The RF electrode was placed under MR guidance on a .2-T system using
rapid fast imaging with steady state precession (FISP) and true FISP
images. A custom 17-gauge electrode was used and was modified in
four sessions to allow circulation of iced saline for cooling during
ablation. Tissue necrosis monitoring and electrode repositioning
were based on rapid T2-weighted and short-inversion-time inversion
recovery (STIR) sequences. Morbidity and toxicity were assessed by
clinical and imaging criteria. The region of tissue destruction was
visible in all 11 tumors treated, as confirmed on subsequent contrast-enhanced
images. No significant morbidity was noted, and patient discomfort
was minimal. In conclusion, interactive MR-guided RF-ITA is feasible
on a clinical .2-T C-arm system with supplemental interventional
accessories with only minor patient morbidity. The ability to completely
ablate tumors with RF-ITA depends on tumor size and vascularity.
1997
Solbiati, L.; Goldberg, S. N.; Ierace, T.; Livraghi, T.; Meloni, F.; Dellanoce, M.; Sironi, S.; Gazelle, G. Scott
Hepatic metastases: percutaneous radio-frequency ablation with cooled-tip electrodes Journal Article
In: Radiology, vol. 205, no. 2, pp. 367-73, 1997, ISSN: 0033-8419 (Print) 0033-8419 (Lin, ().
@article{Solbiati1997a,
title = {Hepatic metastases: percutaneous radio-frequency ablation with cooled-tip
electrodes},
author = {L. Solbiati and S. N. Goldberg and T. Ierace and T. Livraghi and F. Meloni and M. Dellanoce and S. Sironi and G. Scott Gazelle},
url = {http://www.ncbi.nlm.nih.gov/pubmed/9356616},
issn = {0033-8419 (Print) 0033-8419 (Lin},
year = {1997},
date = {1997-11-01},
journal = {Radiology},
volume = {205},
number = {2},
pages = {367-73},
abstract = {PURPOSE: To assess the feasibility and safety of using cooled-tip
electrodes to increase the volume of coagulation necrosis obtained
or reduce the number of treatment sessions necessary with percutaneous
tumor radio-frequency (RF) ablation. MATERIALS AND METHODS: Twenty-nine
patients with 44 hepatic metastases (1.3-5.1 cm diameter) from colorectal (n = 22), gastric (n = 5), pancreatic (n = 1), or breast (n = 1)
carcinoma were treated with RF ablation using cooled-tip, 18-gauge
electrodes with 2-3 cm tip exposure. Each tumor was treated in one
or two treatment sessions. RESULTS: Technical success, ablation of
all visualized tumor, was achieved in 40 (91%) metastases. Findings
at computed tomography (CT) and magnetic resonance (MR) imaging performed
3-6 months after treatment confirmed complete necrosis of the entire
metastasis in 66%. Disease-free survival was 50% at 12 months and
33% at 18 months, with localized progression of disease in 34% of
treated lesions. Overall survival was 100%, 94%, and 89% at 6, 12,
and 18 months, respectively. Only one complication, self-limited
hemorrhage, was seen. CONCLUSION: Use of cooled-tip electrodes was
a safe and feasible adjunct for tumor RF ablation therapy that produced
larger volumes of coagulation necrosis with fewer electrode insertions
than is produced with other RF ablation techniques.},
keywords = {},
pubstate = {published},
tppubtype = {article}
}
PURPOSE: To assess the feasibility and safety of using cooled-tip
electrodes to increase the volume of coagulation necrosis obtained
or reduce the number of treatment sessions necessary with percutaneous
tumor radio-frequency (RF) ablation. MATERIALS AND METHODS: Twenty-nine
patients with 44 hepatic metastases (1.3-5.1 cm diameter) from colorectal (n = 22), gastric (n = 5), pancreatic (n = 1), or breast (n = 1)
carcinoma were treated with RF ablation using cooled-tip, 18-gauge
electrodes with 2-3 cm tip exposure. Each tumor was treated in one
or two treatment sessions. RESULTS: Technical success, ablation of
all visualized tumor, was achieved in 40 (91%) metastases. Findings
at computed tomography (CT) and magnetic resonance (MR) imaging performed
3-6 months after treatment confirmed complete necrosis of the entire
metastasis in 66%. Disease-free survival was 50% at 12 months and
33% at 18 months, with localized progression of disease in 34% of
treated lesions. Overall survival was 100%, 94%, and 89% at 6, 12,
and 18 months, respectively. Only one complication, self-limited
hemorrhage, was seen. CONCLUSION: Use of cooled-tip electrodes was
a safe and feasible adjunct for tumor RF ablation therapy that produced
larger volumes of coagulation necrosis with fewer electrode insertions
than is produced with other RF ablation techniques.
electrodes to increase the volume of coagulation necrosis obtained
or reduce the number of treatment sessions necessary with percutaneous
tumor radio-frequency (RF) ablation. MATERIALS AND METHODS: Twenty-nine
patients with 44 hepatic metastases (1.3-5.1 cm diameter) from colorectal (n = 22), gastric (n = 5), pancreatic (n = 1), or breast (n = 1)
carcinoma were treated with RF ablation using cooled-tip, 18-gauge
electrodes with 2-3 cm tip exposure. Each tumor was treated in one
or two treatment sessions. RESULTS: Technical success, ablation of
all visualized tumor, was achieved in 40 (91%) metastases. Findings
at computed tomography (CT) and magnetic resonance (MR) imaging performed
3-6 months after treatment confirmed complete necrosis of the entire
metastasis in 66%. Disease-free survival was 50% at 12 months and
33% at 18 months, with localized progression of disease in 34% of
treated lesions. Overall survival was 100%, 94%, and 89% at 6, 12,
and 18 months, respectively. Only one complication, self-limited
hemorrhage, was seen. CONCLUSION: Use of cooled-tip electrodes was
a safe and feasible adjunct for tumor RF ablation therapy that produced
larger volumes of coagulation necrosis with fewer electrode insertions
than is produced with other RF ablation techniques.
Steiner, P.; Botnar, R.; Goldberg, S. N.; Gazelle, G. Scott; Debatin, J. F.
Monitoring of radio frequency tissue ablation in an interventional magnetic resonance environment. Preliminary ex vivo and in vivo results Journal Article
In: Invest Radiol, vol. 32, no. 11, pp. 671-8, 1997, ISSN: 0020-9996 (Print) 0020-9996 (Lin, ().
@article{Steiner1997,
title = {Monitoring of radio frequency tissue ablation in an interventional
magnetic resonance environment. Preliminary ex vivo and in vivo results},
author = {P. Steiner and R. Botnar and S. N. Goldberg and G. Scott Gazelle and J. F. Debatin},
url = {http://www.ncbi.nlm.nih.gov/pubmed/9387054},
issn = {0020-9996 (Print) 0020-9996 (Lin},
year = {1997},
date = {1997-11-01},
journal = {Invest Radiol},
volume = {32},
number = {11},
pages = {671-8},
abstract = {RATIONALE AND OBJECTIVES: The authors evaluate the feasibility of
monitoring radio frequency (RF) ablation in an interventional, open-configuration,
0.5-tesla magnetic resonance (MR) environment. METHODS: Ex vivo and
in vivo RF coagulation necrosis were induced in porcine paraspinal
muscle tissue using a 300 kHz monopolar RF generator applying 5 to
20 W over 3 to 9 minutes. Images were acquired simultaneous to RF
application, after RF application, and in an intermittent mode (60
seconds of RF followed by 15 seconds of MR imaging). Temperature
changes were monitored based on amplitude (ex vivo) and phase alterations
(in vivo) of a T1-weighted graded refocused echo (GRE) sequence enabling
an update every 2.5 seconds. A standardized color-coded subtraction
technique enhanced signal changes. Additionally, T2- and T1-weighted
spin echo (SE) images were acquired with and without intravenous
contrast. Macroscopic coagulation size was compared with lesion size
seen on MR images. RESULTS: Although lesion diameters were related
directly to applied RF power, the application mode had no significant
impact on coagulation size (P \> 0.05). As could be expected, MR imaging
during RF ablation resulted in major image distortion. Radio frequency
effects were seen on images acquired in the continuous and intermittent
modes. Coagulation size seen on GRE images correlated well with macroscopy both ex vivo (r = 0.89) and in vivo (r = 0.92). Poorer correlation was found with postinterventional SE sequences (r = 0.78-0.84). CONCLUSIONS:
Magnetic resonance monitoring of RF effects is feasible both ex vivo
as well as in vivo using temperature-sensitive sequences in an open-configuration
MR environment.},
keywords = {},
pubstate = {published},
tppubtype = {article}
}
RATIONALE AND OBJECTIVES: The authors evaluate the feasibility of
monitoring radio frequency (RF) ablation in an interventional, open-configuration,
0.5-tesla magnetic resonance (MR) environment. METHODS: Ex vivo and
in vivo RF coagulation necrosis were induced in porcine paraspinal
muscle tissue using a 300 kHz monopolar RF generator applying 5 to
20 W over 3 to 9 minutes. Images were acquired simultaneous to RF
application, after RF application, and in an intermittent mode (60
seconds of RF followed by 15 seconds of MR imaging). Temperature
changes were monitored based on amplitude (ex vivo) and phase alterations
(in vivo) of a T1-weighted graded refocused echo (GRE) sequence enabling
an update every 2.5 seconds. A standardized color-coded subtraction
technique enhanced signal changes. Additionally, T2- and T1-weighted
spin echo (SE) images were acquired with and without intravenous
contrast. Macroscopic coagulation size was compared with lesion size
seen on MR images. RESULTS: Although lesion diameters were related
directly to applied RF power, the application mode had no significant
impact on coagulation size (P > 0.05). As could be expected, MR imaging
during RF ablation resulted in major image distortion. Radio frequency
effects were seen on images acquired in the continuous and intermittent
modes. Coagulation size seen on GRE images correlated well with macroscopy both ex vivo (r = 0.89) and in vivo (r = 0.92). Poorer correlation was found with postinterventional SE sequences (r = 0.78-0.84). CONCLUSIONS:
Magnetic resonance monitoring of RF effects is feasible both ex vivo
as well as in vivo using temperature-sensitive sequences in an open-configuration
MR environment.
monitoring radio frequency (RF) ablation in an interventional, open-configuration,
0.5-tesla magnetic resonance (MR) environment. METHODS: Ex vivo and
in vivo RF coagulation necrosis were induced in porcine paraspinal
muscle tissue using a 300 kHz monopolar RF generator applying 5 to
20 W over 3 to 9 minutes. Images were acquired simultaneous to RF
application, after RF application, and in an intermittent mode (60
seconds of RF followed by 15 seconds of MR imaging). Temperature
changes were monitored based on amplitude (ex vivo) and phase alterations
(in vivo) of a T1-weighted graded refocused echo (GRE) sequence enabling
an update every 2.5 seconds. A standardized color-coded subtraction
technique enhanced signal changes. Additionally, T2- and T1-weighted
spin echo (SE) images were acquired with and without intravenous
contrast. Macroscopic coagulation size was compared with lesion size
seen on MR images. RESULTS: Although lesion diameters were related
directly to applied RF power, the application mode had no significant
impact on coagulation size (P > 0.05). As could be expected, MR imaging
during RF ablation resulted in major image distortion. Radio frequency
effects were seen on images acquired in the continuous and intermittent
modes. Coagulation size seen on GRE images correlated well with macroscopy both ex vivo (r = 0.89) and in vivo (r = 0.92). Poorer correlation was found with postinterventional SE sequences (r = 0.78-0.84). CONCLUSIONS:
Magnetic resonance monitoring of RF effects is feasible both ex vivo
as well as in vivo using temperature-sensitive sequences in an open-configuration
MR environment.
Hahn, P. F.; Gazelle, G. Scott; Jiang, D. Y.; Compton, C. C.; Goldberg, S. N.; Mueller, P. R.
Liver tumor ablation: real-time monitoring with dynamic CT Journal Article
In: Acad Radiol, vol. 4, no. 9, pp. 634-8, 1997, ISSN: 1076-6332 (Print) 1076-6332 (Lin, ().
@article{Hahn1997,
title = {Liver tumor ablation: real-time monitoring with dynamic CT},
author = {P. F. Hahn and G. Scott Gazelle and D. Y. Jiang and C. C. Compton and S. N. Goldberg and P. R. Mueller},
url = {http://www.ncbi.nlm.nih.gov/pubmed/9288191},
issn = {1076-6332 (Print) 1076-6332 (Lin},
year = {1997},
date = {1997-09-01},
journal = {Acad Radiol},
volume = {4},
number = {9},
pages = {634-8},
abstract = {RATIONALE AND OBJECTIVES: To determine whether incomplete contact
of ethanol with tumor limits the success of percutaneous ethanol
injection therapy. MATERIALS AND METHODS: Percutaneous ethanol injection
was performed in seven normal New Zealand white rabbits and 18 rabbits
with 1-3-cm liver tumors 10-14 days after percutaneous implantation
of suspended tumor cells. A 3-5 mL dose of ethanol was injected at
a rate of 0.2 mL/sec either into normal liver remote from large vessels
or directly into tumor. During and immediately after injection, axial,
2-mm-thick, contrast material-enhanced computed tomography scans
were obtained at reach of three levels every 9 seconds. RESULTS:
In normal animals, virtually all injected ethanol tracked to the
hepatic capsule. As ethanol was injected into tumors, peripheral
tracking, similar to that seen in normal livers, or extratumoral
puddling was observed. Ethanol-tumor contact was incomplete in 16
of 18 animals (89%). Histopathologic analysis showed incomplete tumor
necrosis. CONCLUSION: In this model of hepatic carcinoma metastasis,
the tumor failed to hold sufficient ethanol for successful ablation
by means of percutaneous ethanol injection therapy.},
keywords = {},
pubstate = {published},
tppubtype = {article}
}
RATIONALE AND OBJECTIVES: To determine whether incomplete contact
of ethanol with tumor limits the success of percutaneous ethanol
injection therapy. MATERIALS AND METHODS: Percutaneous ethanol injection
was performed in seven normal New Zealand white rabbits and 18 rabbits
with 1-3-cm liver tumors 10-14 days after percutaneous implantation
of suspended tumor cells. A 3-5 mL dose of ethanol was injected at
a rate of 0.2 mL/sec either into normal liver remote from large vessels
or directly into tumor. During and immediately after injection, axial,
2-mm-thick, contrast material-enhanced computed tomography scans
were obtained at reach of three levels every 9 seconds. RESULTS:
In normal animals, virtually all injected ethanol tracked to the
hepatic capsule. As ethanol was injected into tumors, peripheral
tracking, similar to that seen in normal livers, or extratumoral
puddling was observed. Ethanol-tumor contact was incomplete in 16
of 18 animals (89%). Histopathologic analysis showed incomplete tumor
necrosis. CONCLUSION: In this model of hepatic carcinoma metastasis,
the tumor failed to hold sufficient ethanol for successful ablation
by means of percutaneous ethanol injection therapy.
of ethanol with tumor limits the success of percutaneous ethanol
injection therapy. MATERIALS AND METHODS: Percutaneous ethanol injection
was performed in seven normal New Zealand white rabbits and 18 rabbits
with 1-3-cm liver tumors 10-14 days after percutaneous implantation
of suspended tumor cells. A 3-5 mL dose of ethanol was injected at
a rate of 0.2 mL/sec either into normal liver remote from large vessels
or directly into tumor. During and immediately after injection, axial,
2-mm-thick, contrast material-enhanced computed tomography scans
were obtained at reach of three levels every 9 seconds. RESULTS:
In normal animals, virtually all injected ethanol tracked to the
hepatic capsule. As ethanol was injected into tumors, peripheral
tracking, similar to that seen in normal livers, or extratumoral
puddling was observed. Ethanol-tumor contact was incomplete in 16
of 18 animals (89%). Histopathologic analysis showed incomplete tumor
necrosis. CONCLUSION: In this model of hepatic carcinoma metastasis,
the tumor failed to hold sufficient ethanol for successful ablation
by means of percutaneous ethanol injection therapy.
Lazor, M. A.; Pierce, E. T.; Stanley, G. D.; Cass, J. L.; Halpern, Elkan F.; Bode, Jr. R. H.
Evaluation of the accuracy and response time of STAT-mode continuous cardiac output Journal Article
In: J Cardiothorac Vasc Anesth, vol. 11, no. 4, pp. 432-6, 1997, ISSN: 1053-0770 (Print) 1053-0770 (Lin, ().
@article{Lazor1997,
title = {Evaluation of the accuracy and response time of STAT-mode continuous
cardiac output},
author = {M. A. Lazor and E. T. Pierce and G. D. Stanley and J. L. Cass and Elkan F. Halpern and Jr. R. H. Bode},
url = {http://www.ncbi.nlm.nih.gov/pubmed/9187990},
issn = {1053-0770 (Print) 1053-0770 (Lin},
year = {1997},
date = {1997-06-01},
journal = {J Cardiothorac Vasc Anesth},
volume = {11},
number = {4},
pages = {432-6},
abstract = {OBJECTIVES: This study was conducted to compare continuous cardiac
output (CCO) with bolus thermodilution cardiac output (BTD) at steady
state, and to compare the response time of STAT CCO with that of
trend CCO, mean arterial pressure, and mixed venous oxygen saturation
[SvO2] during an acute hemodynamic change. DESIGN: Prospective study.
SETTING: University hospital. PARTICIPANTS: Twenty-nine patients
undergoing cardiac surgery or liver transplantation. INTERVENTIONS:
STAT and trend CCO were compared with BTD cardiac output during steady
state intraoperatively and postoperatively in the intensive care
unit. Ten patients, who required epicardial pacing after cardiac
surgery, were studied to compare the response time of STAT CCO with
that of trend CCO, mean arterial pressure, and BvO2 after a 10% to
20% increase in pacing rate. MEASUREMENTS AND MAIN RESULTS: A total
of 108 cardiac output data sets were analyzed at steady state. Steady
state was defined as stable heart rate and mean arterial pressure
(+/- 5%) and stable central venous pressure (+/- 2 mmHg) measured
immediately before and after each data set. Cardiac output ranged
from 2.3 to 8.5 L/min. The correlation between STAT CCO and BTD was r = 0.94, and for trend CCO and BTD was r = 0.94. The bies and precision
for STAT CCO versus BTD were 0.06 L/min (Cl 95%: -0.08 to 0.18) and
0.61 L/min. The bias and precision for trend CCO versus BTD were
0.06 L/min (Cl 95%: -0.04 to 0.16) and 0.49 L/min. Eleven data sets
were analyzed to study response time of STAT CCO, which was defined
as the first time the percent change of the mean of each variable
was significantly increased from baseline. Significant increases
in mean arterial pressure and SvO2 were detected after 30 seconds (2.5},
keywords = {},
pubstate = {published},
tppubtype = {article}
}
OBJECTIVES: This study was conducted to compare continuous cardiac
output (CCO) with bolus thermodilution cardiac output (BTD) at steady
state, and to compare the response time of STAT CCO with that of
trend CCO, mean arterial pressure, and mixed venous oxygen saturation
[SvO2] during an acute hemodynamic change. DESIGN: Prospective study.
SETTING: University hospital. PARTICIPANTS: Twenty-nine patients
undergoing cardiac surgery or liver transplantation. INTERVENTIONS:
STAT and trend CCO were compared with BTD cardiac output during steady
state intraoperatively and postoperatively in the intensive care
unit. Ten patients, who required epicardial pacing after cardiac
surgery, were studied to compare the response time of STAT CCO with
that of trend CCO, mean arterial pressure, and BvO2 after a 10% to
20% increase in pacing rate. MEASUREMENTS AND MAIN RESULTS: A total
of 108 cardiac output data sets were analyzed at steady state. Steady
state was defined as stable heart rate and mean arterial pressure
(+/- 5%) and stable central venous pressure (+/- 2 mmHg) measured
immediately before and after each data set. Cardiac output ranged
from 2.3 to 8.5 L/min. The correlation between STAT CCO and BTD was r = 0.94, and for trend CCO and BTD was r = 0.94. The bies and precision
for STAT CCO versus BTD were 0.06 L/min (Cl 95%: -0.08 to 0.18) and
0.61 L/min. The bias and precision for trend CCO versus BTD were
0.06 L/min (Cl 95%: -0.04 to 0.16) and 0.49 L/min. Eleven data sets
were analyzed to study response time of STAT CCO, which was defined
as the first time the percent change of the mean of each variable
was significantly increased from baseline. Significant increases
in mean arterial pressure and SvO2 were detected after 30 seconds (2.5
output (CCO) with bolus thermodilution cardiac output (BTD) at steady
state, and to compare the response time of STAT CCO with that of
trend CCO, mean arterial pressure, and mixed venous oxygen saturation
[SvO2] during an acute hemodynamic change. DESIGN: Prospective study.
SETTING: University hospital. PARTICIPANTS: Twenty-nine patients
undergoing cardiac surgery or liver transplantation. INTERVENTIONS:
STAT and trend CCO were compared with BTD cardiac output during steady
state intraoperatively and postoperatively in the intensive care
unit. Ten patients, who required epicardial pacing after cardiac
surgery, were studied to compare the response time of STAT CCO with
that of trend CCO, mean arterial pressure, and BvO2 after a 10% to
20% increase in pacing rate. MEASUREMENTS AND MAIN RESULTS: A total
of 108 cardiac output data sets were analyzed at steady state. Steady
state was defined as stable heart rate and mean arterial pressure
(+/- 5%) and stable central venous pressure (+/- 2 mmHg) measured
immediately before and after each data set. Cardiac output ranged
from 2.3 to 8.5 L/min. The correlation between STAT CCO and BTD was r = 0.94, and for trend CCO and BTD was r = 0.94. The bies and precision
for STAT CCO versus BTD were 0.06 L/min (Cl 95%: -0.08 to 0.18) and
0.61 L/min. The bias and precision for trend CCO versus BTD were
0.06 L/min (Cl 95%: -0.04 to 0.16) and 0.49 L/min. Eleven data sets
were analyzed to study response time of STAT CCO, which was defined
as the first time the percent change of the mean of each variable
was significantly increased from baseline. Significant increases
in mean arterial pressure and SvO2 were detected after 30 seconds (2.5
Slanetz, P. J.; Moore, R. H.; Hulka, C. A.; Halpern, Elkan F.; Habunek, D. A.; Whitman, G. J.; McCarthy, K. A.; Hall, D. A.; Kopans, D. B.
Screening mammography: effect of national guidelines on current physician practice Journal Article
In: Radiology, vol. 203, no. 2, pp. 335-8, 1997, ISSN: 0033-8419 (Print) 0033-8419 (Lin, ().
@article{Slanetz1997a,
title = {Screening mammography: effect of national guidelines on current physician
practice},
author = {P. J. Slanetz and R. H. Moore and C. A. Hulka and Elkan F. Halpern and D. A. Habunek and G. J. Whitman and K. A. McCarthy and D. A. Hall and D. B. Kopans},
url = {http://www.ncbi.nlm.nih.gov/pubmed/9114084},
issn = {0033-8419 (Print) 0033-8419 (Lin},
year = {1997},
date = {1997-05-01},
journal = {Radiology},
volume = {203},
number = {2},
pages = {335-8},
abstract = {PURPOSE: To evaluate the effect of national breast cancer screening
guidelines on current physician attitudes toward and practice of
screening mammography. MATERIALS AND METHODS: Questionnaire responses
from 278 physicians were analyzed. The questionnaire had four sections:
general information on physician practice and experience, current
use of breast cancer screening, perceptions of screening mammography,
and physician awareness of and response to the controversy in breast
cancer screening. RESULTS: In women aged 40-49 years, 144 (52%) of
278 physicians performed annual clinical breast examination and screening
mammography every 2 years; 57 (21%) favored annual mammography and
clinical breast examination. In women aged 50 years and older, 232
(83%) physicians screened patients annually with clinical breast
examination and mammography. Two hundred seventeen (78%) physicians
were aware of the recommended changes in screening guidelines; 54
(19%) were not aware of the changes. Of those aware of the changes,
56 (26%) changed to the new guidelines, 150 (69%) did not change,
and six (3%) modified their practice somewhat. CONCLUSION: Physician
practice as regards screening mammography is influenced by national
guidelines.},
keywords = {},
pubstate = {published},
tppubtype = {article}
}
PURPOSE: To evaluate the effect of national breast cancer screening
guidelines on current physician attitudes toward and practice of
screening mammography. MATERIALS AND METHODS: Questionnaire responses
from 278 physicians were analyzed. The questionnaire had four sections:
general information on physician practice and experience, current
use of breast cancer screening, perceptions of screening mammography,
and physician awareness of and response to the controversy in breast
cancer screening. RESULTS: In women aged 40-49 years, 144 (52%) of
278 physicians performed annual clinical breast examination and screening
mammography every 2 years; 57 (21%) favored annual mammography and
clinical breast examination. In women aged 50 years and older, 232
(83%) physicians screened patients annually with clinical breast
examination and mammography. Two hundred seventeen (78%) physicians
were aware of the recommended changes in screening guidelines; 54
(19%) were not aware of the changes. Of those aware of the changes,
56 (26%) changed to the new guidelines, 150 (69%) did not change,
and six (3%) modified their practice somewhat. CONCLUSION: Physician
practice as regards screening mammography is influenced by national
guidelines.
guidelines on current physician attitudes toward and practice of
screening mammography. MATERIALS AND METHODS: Questionnaire responses
from 278 physicians were analyzed. The questionnaire had four sections:
general information on physician practice and experience, current
use of breast cancer screening, perceptions of screening mammography,
and physician awareness of and response to the controversy in breast
cancer screening. RESULTS: In women aged 40-49 years, 144 (52%) of
278 physicians performed annual clinical breast examination and screening
mammography every 2 years; 57 (21%) favored annual mammography and
clinical breast examination. In women aged 50 years and older, 232
(83%) physicians screened patients annually with clinical breast
examination and mammography. Two hundred seventeen (78%) physicians
were aware of the recommended changes in screening guidelines; 54
(19%) were not aware of the changes. Of those aware of the changes,
56 (26%) changed to the new guidelines, 150 (69%) did not change,
and six (3%) modified their practice somewhat. CONCLUSION: Physician
practice as regards screening mammography is influenced by national
guidelines.
Hamm, B.; Mahfouz, A. E.; Taupitz, M.; Mitchell, D. G.; Nelson, R.; Halpern, Elkan F.; Speidel, A.; Wolf, K. J.; Saini, S.
Liver metastases: improved detection with dynamic gadolinium-enhanced MR imaging? Journal Article
In: Radiology, vol. 202, no. 3, pp. 677-82, 1997, ISSN: 0033-8419 (Print) 0033-8419 (Lin, ().
@article{Hamm1997,
title = {Liver metastases: improved detection with dynamic gadolinium-enhanced
MR imaging?},
author = {B. Hamm and A. E. Mahfouz and M. Taupitz and D. G. Mitchell and R. Nelson and Elkan F. Halpern and A. Speidel and K. J. Wolf and S. Saini},
url = {http://www.ncbi.nlm.nih.gov/pubmed/9051015},
issn = {0033-8419 (Print) 0033-8419 (Lin},
year = {1997},
date = {1997-03-01},
journal = {Radiology},
volume = {202},
number = {3},
pages = {677-82},
abstract = {PURPOSE: To compare dynamic gadolinium-enhanced with unenhanced magnetic
resonance (MR) imaging in detection of liver metastases. MATERIALS
AND METHODS: Two groups of patients were prospectively examined with
unenhanced and dynamic gadolinium-enhanced MR imaging. The first group (n = 48) had proved liver metastases; the second group (n =
49) did not. One set of unenhanced and one set of gadolinium-enhanced
MR images were selected per patient. Three independent, blinded readers
assessed the images for presence, number, location, and conspicuity
of lesions. Data were analyzed with receiver operating characteristic
curves, and contrast-to-noise ratios were calculated for the images.
RESULTS: There was no statistically significant difference between
the use of unenhanced and gadolinium-enhanced MR images in the differentiation
of patients with from patients without metastases. The numbers of
false-positive and false-negative diagnoses of individual lesions
were higher (not statistically significant) with dynamic MR images
than with unenhanced MR images. At dynamic MR imaging, contrast-to-noise
ratio was highest in the early phase (30 seconds after injection
of the contrast agent) but was not significantly different from the
contrast-to noise ratio of the T2-weighted images. CONCLUSION: Dynamic
gadolinium-enhanced MR imaging showed no improvement over unenhanced
MR imaging in detectability of liver metastases.},
keywords = {},
pubstate = {published},
tppubtype = {article}
}
PURPOSE: To compare dynamic gadolinium-enhanced with unenhanced magnetic
resonance (MR) imaging in detection of liver metastases. MATERIALS
AND METHODS: Two groups of patients were prospectively examined with
unenhanced and dynamic gadolinium-enhanced MR imaging. The first group (n = 48) had proved liver metastases; the second group (n =
49) did not. One set of unenhanced and one set of gadolinium-enhanced
MR images were selected per patient. Three independent, blinded readers
assessed the images for presence, number, location, and conspicuity
of lesions. Data were analyzed with receiver operating characteristic
curves, and contrast-to-noise ratios were calculated for the images.
RESULTS: There was no statistically significant difference between
the use of unenhanced and gadolinium-enhanced MR images in the differentiation
of patients with from patients without metastases. The numbers of
false-positive and false-negative diagnoses of individual lesions
were higher (not statistically significant) with dynamic MR images
than with unenhanced MR images. At dynamic MR imaging, contrast-to-noise
ratio was highest in the early phase (30 seconds after injection
of the contrast agent) but was not significantly different from the
contrast-to noise ratio of the T2-weighted images. CONCLUSION: Dynamic
gadolinium-enhanced MR imaging showed no improvement over unenhanced
MR imaging in detectability of liver metastases.
resonance (MR) imaging in detection of liver metastases. MATERIALS
AND METHODS: Two groups of patients were prospectively examined with
unenhanced and dynamic gadolinium-enhanced MR imaging. The first group (n = 48) had proved liver metastases; the second group (n =
49) did not. One set of unenhanced and one set of gadolinium-enhanced
MR images were selected per patient. Three independent, blinded readers
assessed the images for presence, number, location, and conspicuity
of lesions. Data were analyzed with receiver operating characteristic
curves, and contrast-to-noise ratios were calculated for the images.
RESULTS: There was no statistically significant difference between
the use of unenhanced and gadolinium-enhanced MR images in the differentiation
of patients with from patients without metastases. The numbers of
false-positive and false-negative diagnoses of individual lesions
were higher (not statistically significant) with dynamic MR images
than with unenhanced MR images. At dynamic MR imaging, contrast-to-noise
ratio was highest in the early phase (30 seconds after injection
of the contrast agent) but was not significantly different from the
contrast-to noise ratio of the T2-weighted images. CONCLUSION: Dynamic
gadolinium-enhanced MR imaging showed no improvement over unenhanced
MR imaging in detectability of liver metastases.
Swan, J. Shannon; Fryback, D. G.; Lawrence, W. F.; Katz, D. A.; Heisey, D. M.; Hagenauer, M. E.; Selzer, P. M.; Jacobson, B. K.
MR and conventional angiography: work in progress toward assessing utility in radiology Journal Article
In: Acad Radiol, vol. 4, no. 7, pp. 475-82, 1997, ISSN: 1076-6332 (Print) 1076-6332 (Li, ().
@article{Swan1997,
title = {MR and conventional angiography: work in progress toward assessing utility in radiology},
author = {J. Shannon Swan and D. G. Fryback and W. F. Lawrence and D. A. Katz and D. M. Heisey and M. E. Hagenauer and P. M. Selzer and B. K. Jacobson},
url = {https://www.ncbi.nlm.nih.gov/pubmed/9232166},
doi = {10.1016/s1076-6332(97)80231-0},
issn = {1076-6332 (Print)
1076-6332 (Li},
year = {1997},
date = {1997-01-01},
journal = {Acad Radiol},
volume = {4},
number = {7},
pages = {475-82},
keywords = {},
pubstate = {published},
tppubtype = {article}
}
Solbiati, L.; Ierace, T.; Goldberg, S. N.; Sironi, S.; Livraghi, T.; Fiocca, R.; Servadio, G.; Rizzatto, G.; Mueller, P. R.; Maschio, A. Del; Gazelle, G. Scott
Percutaneous US-guided radio-frequency tissue ablation of liver metastases: treatment and follow-up in 16 patients Journal Article
In: Radiology, vol. 202, no. 1, pp. 195-203, 1997, ISSN: 0033-8419 (Print) 0033-8419 (Lin, ().
@article{Solbiati1997,
title = {Percutaneous US-guided radio-frequency tissue ablation of liver metastases:
treatment and follow-up in 16 patients},
author = {L. Solbiati and T. Ierace and S. N. Goldberg and S. Sironi and T. Livraghi and R. Fiocca and G. Servadio and G. Rizzatto and P. R. Mueller and A. Del Maschio and G. Scott Gazelle},
url = {http://www.ncbi.nlm.nih.gov/pubmed/8988211},
issn = {0033-8419 (Print) 0033-8419 (Lin},
year = {1997},
date = {1997-01-01},
journal = {Radiology},
volume = {202},
number = {1},
pages = {195-203},
abstract = {PURPOSE: To determine the potential efficacy of radio-frequency (RF)
ablation of liver metastases during long-term follow-up. MATERIALS
AND METHODS: Sixteen patients with 31 hepatic metastases were treated
with percutaneous, ultrasound-guided RF ablation. RF was applied
to monopolar electrodes (2-3-cm tip exposure) either individually
or within a multiprobe array (two to four probes) for 6 minutes at
90 degrees C over one to four treatment sessions per metastasis.
RESULTS: In only one of 75 sessions, a moderate complication, self-limited
intraperitoneal hemorrhage, was observed. Four patients (four lesions)
underwent surgical resection 15-60 days after RF treatment. Residual,
viable tumor was seen in all of these patients. The remaining 12
patients were followed up for 9-29 months (mean, 18.1 months). In
these patients, 18 of 27 lesions remained stable or decreased in
size and showed no enhancement at computed tomography and/or magnetic
resonance imaging for at least 9 months. Two patients died of disseminated
disease at 13 months and one at 16 months. Disease-free survival
was achieved in eight patients. CONCLUSIONS: RF ablation appears
to be a simple, safe, and potentially effective treatment for selected
patients with liver metastases and may become a less invasive alternative
to surgical therapy.},
keywords = {},
pubstate = {published},
tppubtype = {article}
}
PURPOSE: To determine the potential efficacy of radio-frequency (RF)
ablation of liver metastases during long-term follow-up. MATERIALS
AND METHODS: Sixteen patients with 31 hepatic metastases were treated
with percutaneous, ultrasound-guided RF ablation. RF was applied
to monopolar electrodes (2-3-cm tip exposure) either individually
or within a multiprobe array (two to four probes) for 6 minutes at
90 degrees C over one to four treatment sessions per metastasis.
RESULTS: In only one of 75 sessions, a moderate complication, self-limited
intraperitoneal hemorrhage, was observed. Four patients (four lesions)
underwent surgical resection 15-60 days after RF treatment. Residual,
viable tumor was seen in all of these patients. The remaining 12
patients were followed up for 9-29 months (mean, 18.1 months). In
these patients, 18 of 27 lesions remained stable or decreased in
size and showed no enhancement at computed tomography and/or magnetic
resonance imaging for at least 9 months. Two patients died of disseminated
disease at 13 months and one at 16 months. Disease-free survival
was achieved in eight patients. CONCLUSIONS: RF ablation appears
to be a simple, safe, and potentially effective treatment for selected
patients with liver metastases and may become a less invasive alternative
to surgical therapy.
ablation of liver metastases during long-term follow-up. MATERIALS
AND METHODS: Sixteen patients with 31 hepatic metastases were treated
with percutaneous, ultrasound-guided RF ablation. RF was applied
to monopolar electrodes (2-3-cm tip exposure) either individually
or within a multiprobe array (two to four probes) for 6 minutes at
90 degrees C over one to four treatment sessions per metastasis.
RESULTS: In only one of 75 sessions, a moderate complication, self-limited
intraperitoneal hemorrhage, was observed. Four patients (four lesions)
underwent surgical resection 15-60 days after RF treatment. Residual,
viable tumor was seen in all of these patients. The remaining 12
patients were followed up for 9-29 months (mean, 18.1 months). In
these patients, 18 of 27 lesions remained stable or decreased in
size and showed no enhancement at computed tomography and/or magnetic
resonance imaging for at least 9 months. Two patients died of disseminated
disease at 13 months and one at 16 months. Disease-free survival
was achieved in eight patients. CONCLUSIONS: RF ablation appears
to be a simple, safe, and potentially effective treatment for selected
patients with liver metastases and may become a less invasive alternative
to surgical therapy.
Trubetskoy, V. S.; Gazelle, G. Scott; Wolf, G. L.; Torchilin, V. P.
In: J Drug Target, vol. 4, pp. 381-8, 1997, ().
@article{Trubetskoy1997,
title = {Block-copolymer of polyethylene glycol and polylysine as a carrier
of organic iodine: design of long-circulating particulate contrast
medium for X-ray computed tomography},
author = {V. S. Trubetskoy and G. Scott Gazelle and G. L. Wolf and V. P. Torchilin},
url = {http://www.ncbi.nlm.nih.gov/pubmed/9239578},
year = {1997},
date = {1997-01-01},
journal = {J Drug Target},
volume = {4},
pages = {381-8},
abstract = {In order to obtain small, polymer-stabilized particulate carriers
for organic iodine to serve as a contrast agent for X-ray computed
tomography (CT) an attempt was made to design a carrier based on
polymeric micelles. Here we describe the synthesis of an iodine-containing
amphiphilic block-copolymer which can micellize in aqueous solutions.
The two blocks of the copolymer consisted of methoxypoly(ethyleneglycol)
and poly[epsilon,N-(triiodobenzoyl)-L-lysine]. Upon dispersion in
water, the block copolymer formed particles with average diameter
80 nm and iodine content up to 44.7 The particles start to dissociate
to the individual polymeric chains in the concentration range of
0.05-0.5 microM in water at 23 degrees C. Upon intravenous injection
at 250 mg of iodine/kg (570 mg of the agent/kg) in rabbits the medium
demonstrated exceptional 24 hr half-life in the blood substantiating
corona/core structure of the particles with PEG chains protecting
the iodine-containing core. The possible use of these particulates
as contrast medium for X-ray computed tomography is discussed.},
keywords = {},
pubstate = {published},
tppubtype = {article}
}
In order to obtain small, polymer-stabilized particulate carriers
for organic iodine to serve as a contrast agent for X-ray computed
tomography (CT) an attempt was made to design a carrier based on
polymeric micelles. Here we describe the synthesis of an iodine-containing
amphiphilic block-copolymer which can micellize in aqueous solutions.
The two blocks of the copolymer consisted of methoxypoly(ethyleneglycol)
and poly[epsilon,N-(triiodobenzoyl)-L-lysine]. Upon dispersion in
water, the block copolymer formed particles with average diameter
80 nm and iodine content up to 44.7 The particles start to dissociate
to the individual polymeric chains in the concentration range of
0.05-0.5 microM in water at 23 degrees C. Upon intravenous injection
at 250 mg of iodine/kg (570 mg of the agent/kg) in rabbits the medium
demonstrated exceptional 24 hr half-life in the blood substantiating
corona/core structure of the particles with PEG chains protecting
the iodine-containing core. The possible use of these particulates
as contrast medium for X-ray computed tomography is discussed.
for organic iodine to serve as a contrast agent for X-ray computed
tomography (CT) an attempt was made to design a carrier based on
polymeric micelles. Here we describe the synthesis of an iodine-containing
amphiphilic block-copolymer which can micellize in aqueous solutions.
The two blocks of the copolymer consisted of methoxypoly(ethyleneglycol)
and poly[epsilon,N-(triiodobenzoyl)-L-lysine]. Upon dispersion in
water, the block copolymer formed particles with average diameter
80 nm and iodine content up to 44.7 The particles start to dissociate
to the individual polymeric chains in the concentration range of
0.05-0.5 microM in water at 23 degrees C. Upon intravenous injection
at 250 mg of iodine/kg (570 mg of the agent/kg) in rabbits the medium
demonstrated exceptional 24 hr half-life in the blood substantiating
corona/core structure of the particles with PEG chains protecting
the iodine-containing core. The possible use of these particulates
as contrast medium for X-ray computed tomography is discussed.
Pauker, S. G.; Stahl, James
Medical informatics: where the action is Journal Article
In: West J Med, vol. 166, pp. 148-50, 1997, ().
@article{Pauker1997,
title = {Medical informatics: where the action is},
author = {S. G. Pauker and James Stahl},
url = {http://www.ncbi.nlm.nih.gov/pubmed/9109336},
year = {1997},
date = {1997-01-01},
journal = {West J Med},
volume = {166},
pages = {148-50},
keywords = {},
pubstate = {published},
tppubtype = {article}
}
Pierce, E. T.; Pomposelli, F. B.; Stanley, G. D.; Lewis, K. P.; Cass, J. L.; LoGerfo, F. W.; Gibbons, G. W.; Campbell, D. R.; Freeman, D. V.; Halpern, Elkan F.; Bode, R. H.
Anesthesia type does not influence early graft patency or limb salvage rates of lower extremity arterial bypass Journal Article
In: J Vasc Surg, vol. 25, pp. 226, 1997, ().
@article{Pierce1997,
title = {Anesthesia type does not influence early graft patency or limb salvage
rates of lower extremity arterial bypass},
author = {E. T. Pierce and F. B. Pomposelli and G. D. Stanley and K. P. Lewis and J. L. Cass and F. W. LoGerfo and G. W. Gibbons and D. R. Campbell and D. V. Freeman and Elkan F. Halpern and R. H. Bode},
url = {http://www.ncbi.nlm.nih.gov/pubmed/9052557},
year = {1997},
date = {1997-01-01},
journal = {J Vasc Surg},
volume = {25},
pages = {226},
abstract = {PURPOSE: The effect of anesthesia type on 30-day graft patency and
limb salvage rates was evaluated in patients who underwent femoral
to distal artery bypass. METHODS: Of 423 patients randomly assigned
to receive general, spinal, or epidural anesthetic, 76 did not meet
protocol standards and 32 had inadequate anesthesia. A chart review
of the remaining 315 patients was undertaken to obtain surgical information
not recorded in the original study. All patients were monitored with
radial and pulmonary artery catheters. After surgery, patients were
in a monitored setting for 48 to 72 hours and had graft function
assessments hourly during the first 24 hours and then every 8 hours
until discharge. RESULTS: Fifty-one patients were lost to follow-up
(15 general, 22 spinal, 14 epidural). Baseline clinical characteristics
were similar for the three groups except prior carotid artery surgery,
which was more common in the spinal group. Indications for surgery
were also similar except for a higher incidence of nonhealing ulcer
in the epidural group. There were no differences among groups for
30-day graft patency with or without reoperation, 30-day graft occlusion,
death, amputation, or length of hospital stay. CONCLUSION: These
results suggest that the type of anesthetic given for femoral to
distal artery bypass does not significantly affect 30-day occlusion
rate, limb salvage rate, or hospital length of stay.},
keywords = {},
pubstate = {published},
tppubtype = {article}
}
PURPOSE: The effect of anesthesia type on 30-day graft patency and
limb salvage rates was evaluated in patients who underwent femoral
to distal artery bypass. METHODS: Of 423 patients randomly assigned
to receive general, spinal, or epidural anesthetic, 76 did not meet
protocol standards and 32 had inadequate anesthesia. A chart review
of the remaining 315 patients was undertaken to obtain surgical information
not recorded in the original study. All patients were monitored with
radial and pulmonary artery catheters. After surgery, patients were
in a monitored setting for 48 to 72 hours and had graft function
assessments hourly during the first 24 hours and then every 8 hours
until discharge. RESULTS: Fifty-one patients were lost to follow-up
(15 general, 22 spinal, 14 epidural). Baseline clinical characteristics
were similar for the three groups except prior carotid artery surgery,
which was more common in the spinal group. Indications for surgery
were also similar except for a higher incidence of nonhealing ulcer
in the epidural group. There were no differences among groups for
30-day graft patency with or without reoperation, 30-day graft occlusion,
death, amputation, or length of hospital stay. CONCLUSION: These
results suggest that the type of anesthetic given for femoral to
distal artery bypass does not significantly affect 30-day occlusion
rate, limb salvage rate, or hospital length of stay.
limb salvage rates was evaluated in patients who underwent femoral
to distal artery bypass. METHODS: Of 423 patients randomly assigned
to receive general, spinal, or epidural anesthetic, 76 did not meet
protocol standards and 32 had inadequate anesthesia. A chart review
of the remaining 315 patients was undertaken to obtain surgical information
not recorded in the original study. All patients were monitored with
radial and pulmonary artery catheters. After surgery, patients were
in a monitored setting for 48 to 72 hours and had graft function
assessments hourly during the first 24 hours and then every 8 hours
until discharge. RESULTS: Fifty-one patients were lost to follow-up
(15 general, 22 spinal, 14 epidural). Baseline clinical characteristics
were similar for the three groups except prior carotid artery surgery,
which was more common in the spinal group. Indications for surgery
were also similar except for a higher incidence of nonhealing ulcer
in the epidural group. There were no differences among groups for
30-day graft patency with or without reoperation, 30-day graft occlusion,
death, amputation, or length of hospital stay. CONCLUSION: These
results suggest that the type of anesthetic given for femoral to
distal artery bypass does not significantly affect 30-day occlusion
rate, limb salvage rate, or hospital length of stay.
Schima, W.; Petersein, J.; Hahn, P. F.; Harisinghani, M.; Halpern, Elkan F.; Saini, S.
Contrast-enhanced MR imaging of the liver: comparison between Gd-BOPTA and Mangafodipir Journal Article
In: J Magn Reson Imaging, vol. 7, pp. 130-5, 1997, ().
@article{Schima1997,
title = {Contrast-enhanced MR imaging of the liver: comparison between Gd-BOPTA
and Mangafodipir},
author = {W. Schima and J. Petersein and P. F. Hahn and M. Harisinghani and Elkan F. Halpern and S. Saini},
url = {http://www.ncbi.nlm.nih.gov/pubmed/9039603},
year = {1997},
date = {1997-01-01},
journal = {J Magn Reson Imaging},
volume = {7},
pages = {130-5},
abstract = {The purpose of the study was to evaluate the MR contrast agents gadolinium
benzyloxypropionictetro-acetate (Gd-BOPTA) and Mangafodipir for liver
enhancement and the lesion-liver contrast on T1W spin-echo (SE) and
gradient-recalled-echo (GRE) images. Fifty-one patients (three groups
of 17 patients each) with known or suspected liver lesions were evaluated
with T1W SE (300/12) and GRE (77-80/2.3-2.5/80 degrees) images before
and after intravenous (IV) Gd-BOPTA (0.1 or 0.05 mmol/kg) or Mangafodipir
(5 mumol/kg) in phase II to III clinical trials. Quantitative analysis
by calculating liver signal-to-noise ratio (SNR), lesion-liver contrast-to-noise
ratio (CNR), and spleen-liver CNR was performed. Liver SNR and spleen-liver
CNR were always significantly increased postcontrast. SNR was highest
after application of 0.1 mmol/kg Gd-BOPTA (51.3 +/- 3.6, P textless
.05). CNR was highest after Mangafodipir (-22.6 +/- 2.7), but this was not significantly different from others (P = .07). Overall, GRE
images were superior to SE images for SNR and CNR. Mangafodipir and
Gd-BOPTA (0.1 mmol/kg) provide equal liver enhancement and lesion
conspicuity postcontrast. By all criteria, contrast-enhanced T1-weighted
GRE were comparable to SE images.},
keywords = {},
pubstate = {published},
tppubtype = {article}
}
The purpose of the study was to evaluate the MR contrast agents gadolinium
benzyloxypropionictetro-acetate (Gd-BOPTA) and Mangafodipir for liver
enhancement and the lesion-liver contrast on T1W spin-echo (SE) and
gradient-recalled-echo (GRE) images. Fifty-one patients (three groups
of 17 patients each) with known or suspected liver lesions were evaluated
with T1W SE (300/12) and GRE (77-80/2.3-2.5/80 degrees) images before
and after intravenous (IV) Gd-BOPTA (0.1 or 0.05 mmol/kg) or Mangafodipir
(5 mumol/kg) in phase II to III clinical trials. Quantitative analysis
by calculating liver signal-to-noise ratio (SNR), lesion-liver contrast-to-noise
ratio (CNR), and spleen-liver CNR was performed. Liver SNR and spleen-liver
CNR were always significantly increased postcontrast. SNR was highest
after application of 0.1 mmol/kg Gd-BOPTA (51.3 +/- 3.6, P textless
.05). CNR was highest after Mangafodipir (-22.6 +/- 2.7), but this was not significantly different from others (P = .07). Overall, GRE
images were superior to SE images for SNR and CNR. Mangafodipir and
Gd-BOPTA (0.1 mmol/kg) provide equal liver enhancement and lesion
conspicuity postcontrast. By all criteria, contrast-enhanced T1-weighted
GRE were comparable to SE images.
benzyloxypropionictetro-acetate (Gd-BOPTA) and Mangafodipir for liver
enhancement and the lesion-liver contrast on T1W spin-echo (SE) and
gradient-recalled-echo (GRE) images. Fifty-one patients (three groups
of 17 patients each) with known or suspected liver lesions were evaluated
with T1W SE (300/12) and GRE (77-80/2.3-2.5/80 degrees) images before
and after intravenous (IV) Gd-BOPTA (0.1 or 0.05 mmol/kg) or Mangafodipir
(5 mumol/kg) in phase II to III clinical trials. Quantitative analysis
by calculating liver signal-to-noise ratio (SNR), lesion-liver contrast-to-noise
ratio (CNR), and spleen-liver CNR was performed. Liver SNR and spleen-liver
CNR were always significantly increased postcontrast. SNR was highest
after application of 0.1 mmol/kg Gd-BOPTA (51.3 +/- 3.6, P textless
.05). CNR was highest after Mangafodipir (-22.6 +/- 2.7), but this was not significantly different from others (P = .07). Overall, GRE
images were superior to SE images for SNR and CNR. Mangafodipir and
Gd-BOPTA (0.1 mmol/kg) provide equal liver enhancement and lesion
conspicuity postcontrast. By all criteria, contrast-enhanced T1-weighted
GRE were comparable to SE images.
Kopans, Daniel B.; Moore, R. H.; McCarthy, K. A.; Hall, D. A.; Hulka, C. A.; Whitman, G. J.; Slanetz, P. J.; Halpern, Elkan F.
Should women with implants or a history of treatment for breast cancer be excluded from mammography screening programs? Journal Article
In: AJR Am J Roentgenol, vol. 168, pp. 29-31, 1997, ().
@article{Kopans1997,
title = {Should women with implants or a history of treatment for breast cancer
be excluded from mammography screening programs?},
author = {Daniel B. Kopans and R. H. Moore and K. A. McCarthy and D. A. Hall and C. A. Hulka and G. J. Whitman and P. J. Slanetz and Elkan F. Halpern},
url = {http://www.ncbi.nlm.nih.gov/pubmed/8976914},
year = {1997},
date = {1997-01-01},
journal = {AJR Am J Roentgenol},
volume = {168},
pages = {29-31},
abstract = {OBJECTIVE: Our objective was to determine whether it is scientifically
justified to require that women with implants or a history of treatment
for breast cancer be screened in a diagnostic mammography setting
and that they be excluded from mammography screening programs. MATERIALS
AND METHODS: The recall rates for women with breast implants or a
history of treatment for breast cancer who were screened in a dedicated
mammography screening program were compared with those of other women
in the screening program. The computerized records for the breast
screening program of the Department of Radiology at our institution
for January 1, 1990, through December 31, 1995, were reviewed. The
recall rates for women who had breast implants and those for women
with a history of treatment for breast cancer were compared with
the recall rates for the other women who underwent screening. Each
recall rate included women who were called back for additional evaluation
in addition to those for whom a biopsy was recommended on the basis
of the screening study. RESULTS: Of 45,134 screening examinations
done during the review period, 43,454 (96 were for women who had
no history of breast cancer or of breast implants; 590 (1 were for
women who had undergone mastectomy; 991 (2 were for women who had
been treated with lumpectomy and irradiation for breast cancer; and
99 (0.2 were for women with breast implants. Among the 43,454 examinations
of women with no history of breast cancer or implants, 3081 examinations
(7 led to interpretations that produced requests for the patient
to return for additional evaluation. Thirty-six women who had been
treated for breast cancer by mastectomy were recalled (6. Seventy-five
women who had undergone lumpectomy and irradiation for breast cancer
were recalled (8. Five women with breast implants were recalled (5.
Statistically, these rates were not significantly different. CONCLUSION:
We find no scientific reason to exclude women who have been treated
for breast cancer or who have breast implants from dedicated screening
programs.},
keywords = {},
pubstate = {published},
tppubtype = {article}
}
OBJECTIVE: Our objective was to determine whether it is scientifically
justified to require that women with implants or a history of treatment
for breast cancer be screened in a diagnostic mammography setting
and that they be excluded from mammography screening programs. MATERIALS
AND METHODS: The recall rates for women with breast implants or a
history of treatment for breast cancer who were screened in a dedicated
mammography screening program were compared with those of other women
in the screening program. The computerized records for the breast
screening program of the Department of Radiology at our institution
for January 1, 1990, through December 31, 1995, were reviewed. The
recall rates for women who had breast implants and those for women
with a history of treatment for breast cancer were compared with
the recall rates for the other women who underwent screening. Each
recall rate included women who were called back for additional evaluation
in addition to those for whom a biopsy was recommended on the basis
of the screening study. RESULTS: Of 45,134 screening examinations
done during the review period, 43,454 (96 were for women who had
no history of breast cancer or of breast implants; 590 (1 were for
women who had undergone mastectomy; 991 (2 were for women who had
been treated with lumpectomy and irradiation for breast cancer; and
99 (0.2 were for women with breast implants. Among the 43,454 examinations
of women with no history of breast cancer or implants, 3081 examinations
(7 led to interpretations that produced requests for the patient
to return for additional evaluation. Thirty-six women who had been
treated for breast cancer by mastectomy were recalled (6. Seventy-five
women who had undergone lumpectomy and irradiation for breast cancer
were recalled (8. Five women with breast implants were recalled (5.
Statistically, these rates were not significantly different. CONCLUSION:
We find no scientific reason to exclude women who have been treated
for breast cancer or who have breast implants from dedicated screening
programs.
justified to require that women with implants or a history of treatment
for breast cancer be screened in a diagnostic mammography setting
and that they be excluded from mammography screening programs. MATERIALS
AND METHODS: The recall rates for women with breast implants or a
history of treatment for breast cancer who were screened in a dedicated
mammography screening program were compared with those of other women
in the screening program. The computerized records for the breast
screening program of the Department of Radiology at our institution
for January 1, 1990, through December 31, 1995, were reviewed. The
recall rates for women who had breast implants and those for women
with a history of treatment for breast cancer were compared with
the recall rates for the other women who underwent screening. Each
recall rate included women who were called back for additional evaluation
in addition to those for whom a biopsy was recommended on the basis
of the screening study. RESULTS: Of 45,134 screening examinations
done during the review period, 43,454 (96 were for women who had
no history of breast cancer or of breast implants; 590 (1 were for
women who had undergone mastectomy; 991 (2 were for women who had
been treated with lumpectomy and irradiation for breast cancer; and
99 (0.2 were for women with breast implants. Among the 43,454 examinations
of women with no history of breast cancer or implants, 3081 examinations
(7 led to interpretations that produced requests for the patient
to return for additional evaluation. Thirty-six women who had been
treated for breast cancer by mastectomy were recalled (6. Seventy-five
women who had undergone lumpectomy and irradiation for breast cancer
were recalled (8. Five women with breast implants were recalled (5.
Statistically, these rates were not significantly different. CONCLUSION:
We find no scientific reason to exclude women who have been treated
for breast cancer or who have breast implants from dedicated screening
programs.
Livraghi, T.; Goldberg, S. N.; Monti, F.; Bizzini, A.; Lazzaroni, S.; Meloni, F.; Pellicano, S.; Solbiati, L.; Gazelle, G. Scott
Saline-enhanced radio-frequency tissue ablation in the treatment of liver metastases Journal Article
In: Radiology, vol. 202, no. 1, pp. 205-10, 1997, ISSN: 0033-8419 (Print) 0033-8419 (Lin, ().
@article{Livraghi1997,
title = {Saline-enhanced radio-frequency tissue ablation in the treatment
of liver metastases},
author = {T. Livraghi and S. N. Goldberg and F. Monti and A. Bizzini and S. Lazzaroni and F. Meloni and S. Pellicano and L. Solbiati and G. Scott Gazelle},
url = {http://www.ncbi.nlm.nih.gov/pubmed/8988212},
issn = {0033-8419 (Print) 0033-8419 (Lin},
year = {1997},
date = {1997-01-01},
journal = {Radiology},
volume = {202},
number = {1},
pages = {205-10},
abstract = {PURPOSE: To assess the effect of intraparenchymal saline injection
on the results of radio-frequency (RF) tissue ablation. MATERIALS
AND METHODS: Ex vivo and in vivo animal RF ablation was performed
with and without intraparenchymal saline injection. Initially, saline
was injected as a bolus (1-20 mL) before RF application. For subsequent
in vivo studies, saline was injected as a bolus before RF application
or continuously (1 mL/min) during RF application. Finally, 14 patients
with liver metastases and one patient with primary cholangiocarcinoma
were treated with the continuous infusion technique. A single RF
electrode (tip exposure, 1-3 cm) was used with various ablation parameters.
RESULTS: With pretreatment bolus injection of saline, lesions measured
1.4 cm +/- 0.1, 1.6 cm +/- 0.2, and 1.2 cm +/- 0.1 in ex vivo liver,
in vivo animal muscle, and in vivo animal liver, respectively. Without
saline enhancement, lesion sizes were 1.0 +/- 0.2, 1.2 +/- 0.2, and
0.8 +/- 0.1 cm, respectively. With continuous saline injection in
in vivo pig liver, lesion size was 1.8 - 4.1 cm in diameter. In human
tumors, necrosis volume was variable, but complete necrosis was seen
in 13 of 25 lesions (diameter, 1.2-3.9 cm). Partial necrosis greater
than 50% was seen in 12 lesions (diameter, 1.5-4.5 cm). CONCLUSION:
Saline-enhanced RF ablation might permit percutaneous destruction
of large liver lesions.},
keywords = {},
pubstate = {published},
tppubtype = {article}
}
PURPOSE: To assess the effect of intraparenchymal saline injection
on the results of radio-frequency (RF) tissue ablation. MATERIALS
AND METHODS: Ex vivo and in vivo animal RF ablation was performed
with and without intraparenchymal saline injection. Initially, saline
was injected as a bolus (1-20 mL) before RF application. For subsequent
in vivo studies, saline was injected as a bolus before RF application
or continuously (1 mL/min) during RF application. Finally, 14 patients
with liver metastases and one patient with primary cholangiocarcinoma
were treated with the continuous infusion technique. A single RF
electrode (tip exposure, 1-3 cm) was used with various ablation parameters.
RESULTS: With pretreatment bolus injection of saline, lesions measured
1.4 cm +/- 0.1, 1.6 cm +/- 0.2, and 1.2 cm +/- 0.1 in ex vivo liver,
in vivo animal muscle, and in vivo animal liver, respectively. Without
saline enhancement, lesion sizes were 1.0 +/- 0.2, 1.2 +/- 0.2, and
0.8 +/- 0.1 cm, respectively. With continuous saline injection in
in vivo pig liver, lesion size was 1.8 - 4.1 cm in diameter. In human
tumors, necrosis volume was variable, but complete necrosis was seen
in 13 of 25 lesions (diameter, 1.2-3.9 cm). Partial necrosis greater
than 50% was seen in 12 lesions (diameter, 1.5-4.5 cm). CONCLUSION:
Saline-enhanced RF ablation might permit percutaneous destruction
of large liver lesions.
on the results of radio-frequency (RF) tissue ablation. MATERIALS
AND METHODS: Ex vivo and in vivo animal RF ablation was performed
with and without intraparenchymal saline injection. Initially, saline
was injected as a bolus (1-20 mL) before RF application. For subsequent
in vivo studies, saline was injected as a bolus before RF application
or continuously (1 mL/min) during RF application. Finally, 14 patients
with liver metastases and one patient with primary cholangiocarcinoma
were treated with the continuous infusion technique. A single RF
electrode (tip exposure, 1-3 cm) was used with various ablation parameters.
RESULTS: With pretreatment bolus injection of saline, lesions measured
1.4 cm +/- 0.1, 1.6 cm +/- 0.2, and 1.2 cm +/- 0.1 in ex vivo liver,
in vivo animal muscle, and in vivo animal liver, respectively. Without
saline enhancement, lesion sizes were 1.0 +/- 0.2, 1.2 +/- 0.2, and
0.8 +/- 0.1 cm, respectively. With continuous saline injection in
in vivo pig liver, lesion size was 1.8 - 4.1 cm in diameter. In human
tumors, necrosis volume was variable, but complete necrosis was seen
in 13 of 25 lesions (diameter, 1.2-3.9 cm). Partial necrosis greater
than 50% was seen in 12 lesions (diameter, 1.5-4.5 cm). CONCLUSION:
Saline-enhanced RF ablation might permit percutaneous destruction
of large liver lesions.
Goldberg, S. N.; Ryan, T. P.; Hahn, P. F.; Schima, W.; Dawson, S. L.; Lawes, K. R.; Mueller, P. R.; Gazelle, G. Scott
Transluminal radiofrequency tissue ablation with use of metallic stents Journal Article
In: J Vasc Interv Radiol, vol. 8, pp. 835-43, 1997, ().
@article{Goldberg1997a,
title = {Transluminal radiofrequency tissue ablation with use of metallic
stents},
author = {S. N. Goldberg and T. P. Ryan and P. F. Hahn and W. Schima and S. L. Dawson and K. R. Lawes and P. R. Mueller and G. Scott Gazelle},
url = {http://www.ncbi.nlm.nih.gov/pubmed/9314376},
year = {1997},
date = {1997-01-01},
journal = {J Vasc Interv Radiol},
volume = {8},
pages = {835-43},
abstract = {PURPOSE: To determine if transluminal coagulative necrosis can be
induced by applying radiofrequency (RF) energy to indwelling metallic
stents. MATERIALS AND METHODS: RF energy was applied to metallic
alloy stents (20-68 mm length, 5-16 mm diameter) in tissue phantom (n = 31), ex vivo bovine liver (n = 10), and in vivo porcine hepatic veins (n = 4). For ex vivo and in vivo liver experiments, RF was
applied for 5-6 minutes, titrating generator output to produce 85
degrees-95 degrees C temperatures at the stent surface. Local and
remote temperature sensing was performed. Imaging and pathologic
studies documented the extent of coagulation necrosis. RESULTS: Phantom
studies demonstrated uniform temperature distribution along the entire
stent length for all Elgiloy stents powered for 2 minutes with a
minimum of 120 watts. Shorter stents required less power or reduced
time to achieve uniform temperature. In ex vivo liver, 25-mm stents (n = 5) showed 8-10 mm of uniform circumferential coagulation necrosis
along the entire stent length. Fifty-millimeter stents showed less
uniform coagulation necrosis. For the in vivo stents (20 mm), 8-10
mm of uniform circumferential coagulation necrosis surrounded the
stent along its entire length. CONCLUSION: Metallic stents can be
used to deliver transluminal RF energy from an external source, inducing
heat deposition with resultant circumferential tissue coagulation.
Clinical applications might include reduction of intimal proliferation
in vascular diseases and/or treatment of periluminal tumors compressing
the bile ducts, the urethra, or other luminal structures.},
keywords = {},
pubstate = {published},
tppubtype = {article}
}
PURPOSE: To determine if transluminal coagulative necrosis can be
induced by applying radiofrequency (RF) energy to indwelling metallic
stents. MATERIALS AND METHODS: RF energy was applied to metallic
alloy stents (20-68 mm length, 5-16 mm diameter) in tissue phantom (n = 31), ex vivo bovine liver (n = 10), and in vivo porcine hepatic veins (n = 4). For ex vivo and in vivo liver experiments, RF was
applied for 5-6 minutes, titrating generator output to produce 85
degrees-95 degrees C temperatures at the stent surface. Local and
remote temperature sensing was performed. Imaging and pathologic
studies documented the extent of coagulation necrosis. RESULTS: Phantom
studies demonstrated uniform temperature distribution along the entire
stent length for all Elgiloy stents powered for 2 minutes with a
minimum of 120 watts. Shorter stents required less power or reduced
time to achieve uniform temperature. In ex vivo liver, 25-mm stents (n = 5) showed 8-10 mm of uniform circumferential coagulation necrosis
along the entire stent length. Fifty-millimeter stents showed less
uniform coagulation necrosis. For the in vivo stents (20 mm), 8-10
mm of uniform circumferential coagulation necrosis surrounded the
stent along its entire length. CONCLUSION: Metallic stents can be
used to deliver transluminal RF energy from an external source, inducing
heat deposition with resultant circumferential tissue coagulation.
Clinical applications might include reduction of intimal proliferation
in vascular diseases and/or treatment of periluminal tumors compressing
the bile ducts, the urethra, or other luminal structures.
induced by applying radiofrequency (RF) energy to indwelling metallic
stents. MATERIALS AND METHODS: RF energy was applied to metallic
alloy stents (20-68 mm length, 5-16 mm diameter) in tissue phantom (n = 31), ex vivo bovine liver (n = 10), and in vivo porcine hepatic veins (n = 4). For ex vivo and in vivo liver experiments, RF was
applied for 5-6 minutes, titrating generator output to produce 85
degrees-95 degrees C temperatures at the stent surface. Local and
remote temperature sensing was performed. Imaging and pathologic
studies documented the extent of coagulation necrosis. RESULTS: Phantom
studies demonstrated uniform temperature distribution along the entire
stent length for all Elgiloy stents powered for 2 minutes with a
minimum of 120 watts. Shorter stents required less power or reduced
time to achieve uniform temperature. In ex vivo liver, 25-mm stents (n = 5) showed 8-10 mm of uniform circumferential coagulation necrosis
along the entire stent length. Fifty-millimeter stents showed less
uniform coagulation necrosis. For the in vivo stents (20 mm), 8-10
mm of uniform circumferential coagulation necrosis surrounded the
stent along its entire length. CONCLUSION: Metallic stents can be
used to deliver transluminal RF energy from an external source, inducing
heat deposition with resultant circumferential tissue coagulation.
Clinical applications might include reduction of intimal proliferation
in vascular diseases and/or treatment of periluminal tumors compressing
the bile ducts, the urethra, or other luminal structures.
Graf, O.; Gazelle, G. Scott; Kreuzer, S.; Halpern, Elkan F.; Boehm, P.; Lechner, G.; Mueller, P. R.
Enhancement of hepatic parenchyma, aorta, and portal vein in helical CT: comparison of iodixanol and iopromide Journal Article
In: AJR Am J Roentgenol, vol. 168, no. 1, pp. 213-7, 1997, ISSN: 0361-803X (Print) 0361-803X (Lin, ().
@article{Graf1997,
title = {Enhancement of hepatic parenchyma, aorta, and portal vein in helical
CT: comparison of iodixanol and iopromide},
author = {O. Graf and G. Scott Gazelle and S. Kreuzer and Elkan F. Halpern and P. Boehm and G. Lechner and P. R. Mueller},
url = {http://www.ncbi.nlm.nih.gov/pubmed/8976948},
issn = {0361-803X (Print) 0361-803X (Lin},
year = {1997},
date = {1997-01-01},
journal = {AJR Am J Roentgenol},
volume = {168},
number = {1},
pages = {213-7},
abstract = {OBJECTIVE: The purpose of this study was to determine hepatic, aortic,
and portal vein enhancement with a new dimeric, nonionic, isotonic
contrast medium (iodixanol) in a routinely performed helical CT protocol
and compare enhancement characteristics with those of a monomeric,
nonionic, low-osmolality contrast medium (iopromide). SUBJECTS AND
METHODS: In 81 patients, we injected 150 ml of iodixanol (320 mg
I/ml), iodixanol (300 mg I/ml), or iopromide (300 mg I/ml). Injection
rate was 5 ml/sec. A dual-phase helical CT scan was obtained (first
helical scan began at 30 sec. second helical scan began at 70 sec),
and enhancement characteristics were assessed. Results were analyzed
taking into account various intrinsic parameters of patients. RESULTS:
During the second imaging phase, iodixanol at 320 mg I/ml and iodixanol
at 300 mg I/ml provided significantly higher enhancement of the liver
(75 H, 69 H, 62 H), aorta (144 H, 140 H, 122 H), and portal vein
(147 H, 147 H, 118 H) than did iopromide at 300 mg I/ml. No significant
differences were observed during the first imaging phase. CONCLUSION:
The combination of higher vascular and parenchymal enhancement levels
after injection of the isotonic agent may represent a different quality
of tissue enhancement. Such an enhancement would be characterized
more by a higher contribution of the blood pool compartment to absolute
enhancement levels than by a contribution of the interstitial compartment.
Further studies are needed to determine whether the use of isotonic
agents effects lesion conspicuity.},
keywords = {},
pubstate = {published},
tppubtype = {article}
}
OBJECTIVE: The purpose of this study was to determine hepatic, aortic,
and portal vein enhancement with a new dimeric, nonionic, isotonic
contrast medium (iodixanol) in a routinely performed helical CT protocol
and compare enhancement characteristics with those of a monomeric,
nonionic, low-osmolality contrast medium (iopromide). SUBJECTS AND
METHODS: In 81 patients, we injected 150 ml of iodixanol (320 mg
I/ml), iodixanol (300 mg I/ml), or iopromide (300 mg I/ml). Injection
rate was 5 ml/sec. A dual-phase helical CT scan was obtained (first
helical scan began at 30 sec. second helical scan began at 70 sec),
and enhancement characteristics were assessed. Results were analyzed
taking into account various intrinsic parameters of patients. RESULTS:
During the second imaging phase, iodixanol at 320 mg I/ml and iodixanol
at 300 mg I/ml provided significantly higher enhancement of the liver
(75 H, 69 H, 62 H), aorta (144 H, 140 H, 122 H), and portal vein
(147 H, 147 H, 118 H) than did iopromide at 300 mg I/ml. No significant
differences were observed during the first imaging phase. CONCLUSION:
The combination of higher vascular and parenchymal enhancement levels
after injection of the isotonic agent may represent a different quality
of tissue enhancement. Such an enhancement would be characterized
more by a higher contribution of the blood pool compartment to absolute
enhancement levels than by a contribution of the interstitial compartment.
Further studies are needed to determine whether the use of isotonic
agents effects lesion conspicuity.
and portal vein enhancement with a new dimeric, nonionic, isotonic
contrast medium (iodixanol) in a routinely performed helical CT protocol
and compare enhancement characteristics with those of a monomeric,
nonionic, low-osmolality contrast medium (iopromide). SUBJECTS AND
METHODS: In 81 patients, we injected 150 ml of iodixanol (320 mg
I/ml), iodixanol (300 mg I/ml), or iopromide (300 mg I/ml). Injection
rate was 5 ml/sec. A dual-phase helical CT scan was obtained (first
helical scan began at 30 sec. second helical scan began at 70 sec),
and enhancement characteristics were assessed. Results were analyzed
taking into account various intrinsic parameters of patients. RESULTS:
During the second imaging phase, iodixanol at 320 mg I/ml and iodixanol
at 300 mg I/ml provided significantly higher enhancement of the liver
(75 H, 69 H, 62 H), aorta (144 H, 140 H, 122 H), and portal vein
(147 H, 147 H, 118 H) than did iopromide at 300 mg I/ml. No significant
differences were observed during the first imaging phase. CONCLUSION:
The combination of higher vascular and parenchymal enhancement levels
after injection of the isotonic agent may represent a different quality
of tissue enhancement. Such an enhancement would be characterized
more by a higher contribution of the blood pool compartment to absolute
enhancement levels than by a contribution of the interstitial compartment.
Further studies are needed to determine whether the use of isotonic
agents effects lesion conspicuity.
Haimovici, J. B.; Trotman-Dickenson, B.; Halpern, Elkan F.; Dec, G. W.; Ginns, L. C.; Shepard, J. A.; McLoud, T. C.
In: Acad Radiol, vol. 4, pp. 327-34, 1997, ().
@article{Haimovici1997,
title = {Relationship between pulmonary artery diameter at computed tomography
and pulmonary artery pressures at right-sided heart catheterization.
Massachusetts General Hospital Lung Transplantation Program},
author = {J. B. Haimovici and B. Trotman-Dickenson and Elkan F. Halpern and G. W. Dec and L. C. Ginns and J. A. Shepard and T. C. McLoud},
url = {http://www.ncbi.nlm.nih.gov/pubmed/9156228},
year = {1997},
date = {1997-01-01},
journal = {Acad Radiol},
volume = {4},
pages = {327-34},
abstract = {RATIONALE AND OBJECTIVES: The purpose of the study was to determine
the relationship between pulmonary artery (PA) size at computed tomography
(CT) and PA pressures, to develop a noninvasive CT method of PA pressure
measurement, and to determine a PA diameter that can enable differentiation
of normal subjects from those with pulmonary hypertension. METHODS:
PA vessel diameters in 55 candidates for lung and heart-lung transplantation
were measured at CT and correlated with PA pressures with both linear
and stepwise multiple regression. The multiple regression equations
were then tested prospectively in 35 pretransplantation patients.
RESULTS: Combined main and left main PA cross-sectional area corrected
for body surface area showed the best correlation with mean PA pressure (r = .87). The multiple regression equations helped predict mean
PA pressure within 5 mm Hg in 50% of patients with chronic lung disease
and in only 8% of patients with pulmonary vascular disease. CONCLUSION:
There was a very good correlation between main and left main PA size
and mean PA pressure. At present, however, CT has not demonstrated
sufficient accuracy to be used clinically.},
keywords = {},
pubstate = {published},
tppubtype = {article}
}
RATIONALE AND OBJECTIVES: The purpose of the study was to determine
the relationship between pulmonary artery (PA) size at computed tomography
(CT) and PA pressures, to develop a noninvasive CT method of PA pressure
measurement, and to determine a PA diameter that can enable differentiation
of normal subjects from those with pulmonary hypertension. METHODS:
PA vessel diameters in 55 candidates for lung and heart-lung transplantation
were measured at CT and correlated with PA pressures with both linear
and stepwise multiple regression. The multiple regression equations
were then tested prospectively in 35 pretransplantation patients.
RESULTS: Combined main and left main PA cross-sectional area corrected
for body surface area showed the best correlation with mean PA pressure (r = .87). The multiple regression equations helped predict mean
PA pressure within 5 mm Hg in 50% of patients with chronic lung disease
and in only 8% of patients with pulmonary vascular disease. CONCLUSION:
There was a very good correlation between main and left main PA size
and mean PA pressure. At present, however, CT has not demonstrated
sufficient accuracy to be used clinically.
the relationship between pulmonary artery (PA) size at computed tomography
(CT) and PA pressures, to develop a noninvasive CT method of PA pressure
measurement, and to determine a PA diameter that can enable differentiation
of normal subjects from those with pulmonary hypertension. METHODS:
PA vessel diameters in 55 candidates for lung and heart-lung transplantation
were measured at CT and correlated with PA pressures with both linear
and stepwise multiple regression. The multiple regression equations
were then tested prospectively in 35 pretransplantation patients.
RESULTS: Combined main and left main PA cross-sectional area corrected
for body surface area showed the best correlation with mean PA pressure (r = .87). The multiple regression equations helped predict mean
PA pressure within 5 mm Hg in 50% of patients with chronic lung disease
and in only 8% of patients with pulmonary vascular disease. CONCLUSION:
There was a very good correlation between main and left main PA size
and mean PA pressure. At present, however, CT has not demonstrated
sufficient accuracy to be used clinically.
Harisinghani, M. G.; Saini, S.; Weissleder, R.; Halpern, Elkan F.; Schima, W.; Rubin, D. L.; Stillman, A. E.; Sica, G. T.; Small, W. C.; Hahn, P. F.
In: Radiology, vol. 202, pp. 687-91, 1997, ().
@article{Harisinghani1997,
title = {Differentiation of liver hemangiomas from metastases and hepatocellular
carcinoma at MR imaging enhanced with blood-pool contrast agent Code-7227},
author = {M. G. Harisinghani and S. Saini and R. Weissleder and Elkan F. Halpern and W. Schima and D. L. Rubin and A. E. Stillman and G. T. Sica and W. C. Small and P. F. Hahn},
url = {http://www.ncbi.nlm.nih.gov/pubmed/9051017},
year = {1997},
date = {1997-01-01},
journal = {Radiology},
volume = {202},
pages = {687-91},
abstract = {PURPOSE: To evaluate differentiation of liver lesions at magnetic
resonance (MR) imaging enhanced with Code-7227. MATERIALS AND METHODS:
Thirty-five patients with 38 proved liver lesions (15 hemangiomas,
17 metastases, six hepatocellular carcinomas [HCCs]) underwent T1-weighted
gradient-echo and T2-weighted fast-spin-echo MR imaging at 1.5 T
before and after intravenous administration of Code-7227 (1.1 mg
iron per kilogram of body weight). RESULTS: In hemangiomas, the mean
contrast-to-noise ratio on precontrast and postcontrast images, respectively,
increased from -4.51 +/- 4.7 (standard deviation) to 5.19 +/- 6.3
on T1-weighted images and decreased from 14.73 +/- 7.4 to 0.64 +/-
5.1 on T2-weighted images. In comparison, metastases remained hypointense
to liver on T1-weighted images (from -5.77 +/- 5.9 to -7.8 +/- 6.8)
and hyperintense on T2-weighted images (from 8.73 +/- 5.4 to 12.61
+/- 6.1). Although HCC enhanced more than metastases, they also remained
hypointense to liver on T1-weighted images (from -4.87 +/- 6.1 to
-1.79 +/- 5.7) and hyperintense on T2-weighted images (from 10.12
+/- 7.9 to 8.7 +/- 6.4). The degree of enhancement on T1-weighted
images and of signal intensity drop on T2-weighted images were significantly
lower in malignant liver masses than in hemangiomas (P textless .001).
CONCLUSION: Distinctly different enhancement patterns with Code-7227
helped accurate differentiation of liver lesions.},
keywords = {},
pubstate = {published},
tppubtype = {article}
}
PURPOSE: To evaluate differentiation of liver lesions at magnetic
resonance (MR) imaging enhanced with Code-7227. MATERIALS AND METHODS:
Thirty-five patients with 38 proved liver lesions (15 hemangiomas,
17 metastases, six hepatocellular carcinomas [HCCs]) underwent T1-weighted
gradient-echo and T2-weighted fast-spin-echo MR imaging at 1.5 T
before and after intravenous administration of Code-7227 (1.1 mg
iron per kilogram of body weight). RESULTS: In hemangiomas, the mean
contrast-to-noise ratio on precontrast and postcontrast images, respectively,
increased from -4.51 +/- 4.7 (standard deviation) to 5.19 +/- 6.3
on T1-weighted images and decreased from 14.73 +/- 7.4 to 0.64 +/-
5.1 on T2-weighted images. In comparison, metastases remained hypointense
to liver on T1-weighted images (from -5.77 +/- 5.9 to -7.8 +/- 6.8)
and hyperintense on T2-weighted images (from 8.73 +/- 5.4 to 12.61
+/- 6.1). Although HCC enhanced more than metastases, they also remained
hypointense to liver on T1-weighted images (from -4.87 +/- 6.1 to
-1.79 +/- 5.7) and hyperintense on T2-weighted images (from 10.12
+/- 7.9 to 8.7 +/- 6.4). The degree of enhancement on T1-weighted
images and of signal intensity drop on T2-weighted images were significantly
lower in malignant liver masses than in hemangiomas (P textless .001).
CONCLUSION: Distinctly different enhancement patterns with Code-7227
helped accurate differentiation of liver lesions.
resonance (MR) imaging enhanced with Code-7227. MATERIALS AND METHODS:
Thirty-five patients with 38 proved liver lesions (15 hemangiomas,
17 metastases, six hepatocellular carcinomas [HCCs]) underwent T1-weighted
gradient-echo and T2-weighted fast-spin-echo MR imaging at 1.5 T
before and after intravenous administration of Code-7227 (1.1 mg
iron per kilogram of body weight). RESULTS: In hemangiomas, the mean
contrast-to-noise ratio on precontrast and postcontrast images, respectively,
increased from -4.51 +/- 4.7 (standard deviation) to 5.19 +/- 6.3
on T1-weighted images and decreased from 14.73 +/- 7.4 to 0.64 +/-
5.1 on T2-weighted images. In comparison, metastases remained hypointense
to liver on T1-weighted images (from -5.77 +/- 5.9 to -7.8 +/- 6.8)
and hyperintense on T2-weighted images (from 8.73 +/- 5.4 to 12.61
+/- 6.1). Although HCC enhanced more than metastases, they also remained
hypointense to liver on T1-weighted images (from -4.87 +/- 6.1 to
-1.79 +/- 5.7) and hyperintense on T2-weighted images (from 10.12
+/- 7.9 to 8.7 +/- 6.4). The degree of enhancement on T1-weighted
images and of signal intensity drop on T2-weighted images were significantly
lower in malignant liver masses than in hemangiomas (P textless .001).
CONCLUSION: Distinctly different enhancement patterns with Code-7227
helped accurate differentiation of liver lesions.
Hulka, C. A.; Slanetz, P. J.; Halpern, Elkan F.; Hall, D. A.; McCarthy, K. A.; Moore, R.; Boutin, S.; Kopans, D. B.
Patients' opinion of mammography screening services: immediate results versus delayed results due to interpretation by two observers Journal Article
In: AJR Am J Roentgenol, vol. 168, pp. 1085-9, 1997, ().
@article{Hulka1997,
title = {Patients' opinion of mammography screening services: immediate results
versus delayed results due to interpretation by two observers},
author = {C. A. Hulka and P. J. Slanetz and Elkan F. Halpern and D. A. Hall and K. A. McCarthy and R. Moore and S. Boutin and D. B. Kopans},
url = {http://www.ncbi.nlm.nih.gov/pubmed/9124120},
year = {1997},
date = {1997-01-01},
journal = {AJR Am J Roentgenol},
volume = {168},
pages = {1085-9},
abstract = {OBJECTIVE: The purpose of this study was to evaluate by random questionnaire
mailings the preferences of women who have undergone mammography
in our region regarding communication of mammography screening results.
MATERIALS AND METHODS: Questionnaires were mailed to 400 randomly
selected women who were more than 35 years old and who had been treated
at our institution for medical or surgical reasons. Questions regarding
use of mammography screening at our institution versus services at
other locations were included. The questionnaire described two possible
mammography services; either a double reading service that would
provide delayed reports (DRDR) with the benefit of extra cancers
detected, and a service that provides immediate reports given directly
to the patient by an on-site radiologist. The presentation of the
services was reversed in half the questionnaires to avoid bias. Patients'
choices were collected, as were demographic data. The choice of one
system over the other was evaluated using the one-sample lest for
binomial probability. The chi-square test was used to determine if
the order of questions on the survey or the site of patients' screening
mammography affected responses. RESULTS: The response rate was 42% (n = 168). Of these, one response informed us of the death of a patient. Of the remaining 167 respondents, 75% (n = 126) preferred the DRDR system, 13% (n = 22) preferred the system providing immediate results
(p textless .0001), and the other 19 respondents did not select a
preference. Of the 167 respondents, 156 answered the question regarding
previous screening mammography experience. Of the 105 patients who had undergone screening mammography at our institution, 78% (n =
82) preferred the DRDR system. Of the 51 patients who had undergone
mammography elsewhere or who had never undergone mammography, 75% (n = 38) preferred the DRDR system. We found that ordering of presentation
of the systems in the questionnaire had no effect on responses. Likewise,
whether a respondent had undergone mammography at our institution had no effect on responses (p = 1.0). CONCLUSION: A statistically
significant number of women who responded to our questionnaire preferred
the DRDR system of reporting screening mammographic results. Educational
material about double reading that we included with each patient's
questionnaire could account for these results. If the use of a second
interpreter is feasible and is done for batch interpretation of screening
mammograms, then education of patients about this process may increase
acceptance of a delayed mammographic report.},
keywords = {},
pubstate = {published},
tppubtype = {article}
}
OBJECTIVE: The purpose of this study was to evaluate by random questionnaire
mailings the preferences of women who have undergone mammography
in our region regarding communication of mammography screening results.
MATERIALS AND METHODS: Questionnaires were mailed to 400 randomly
selected women who were more than 35 years old and who had been treated
at our institution for medical or surgical reasons. Questions regarding
use of mammography screening at our institution versus services at
other locations were included. The questionnaire described two possible
mammography services; either a double reading service that would
provide delayed reports (DRDR) with the benefit of extra cancers
detected, and a service that provides immediate reports given directly
to the patient by an on-site radiologist. The presentation of the
services was reversed in half the questionnaires to avoid bias. Patients'
choices were collected, as were demographic data. The choice of one
system over the other was evaluated using the one-sample lest for
binomial probability. The chi-square test was used to determine if
the order of questions on the survey or the site of patients' screening
mammography affected responses. RESULTS: The response rate was 42% (n = 168). Of these, one response informed us of the death of a patient. Of the remaining 167 respondents, 75% (n = 126) preferred the DRDR system, 13% (n = 22) preferred the system providing immediate results
(p textless .0001), and the other 19 respondents did not select a
preference. Of the 167 respondents, 156 answered the question regarding
previous screening mammography experience. Of the 105 patients who had undergone screening mammography at our institution, 78% (n =
82) preferred the DRDR system. Of the 51 patients who had undergone
mammography elsewhere or who had never undergone mammography, 75% (n = 38) preferred the DRDR system. We found that ordering of presentation
of the systems in the questionnaire had no effect on responses. Likewise,
whether a respondent had undergone mammography at our institution had no effect on responses (p = 1.0). CONCLUSION: A statistically
significant number of women who responded to our questionnaire preferred
the DRDR system of reporting screening mammographic results. Educational
material about double reading that we included with each patient's
questionnaire could account for these results. If the use of a second
interpreter is feasible and is done for batch interpretation of screening
mammograms, then education of patients about this process may increase
acceptance of a delayed mammographic report.
mailings the preferences of women who have undergone mammography
in our region regarding communication of mammography screening results.
MATERIALS AND METHODS: Questionnaires were mailed to 400 randomly
selected women who were more than 35 years old and who had been treated
at our institution for medical or surgical reasons. Questions regarding
use of mammography screening at our institution versus services at
other locations were included. The questionnaire described two possible
mammography services; either a double reading service that would
provide delayed reports (DRDR) with the benefit of extra cancers
detected, and a service that provides immediate reports given directly
to the patient by an on-site radiologist. The presentation of the
services was reversed in half the questionnaires to avoid bias. Patients'
choices were collected, as were demographic data. The choice of one
system over the other was evaluated using the one-sample lest for
binomial probability. The chi-square test was used to determine if
the order of questions on the survey or the site of patients' screening
mammography affected responses. RESULTS: The response rate was 42% (n = 168). Of these, one response informed us of the death of a patient. Of the remaining 167 respondents, 75% (n = 126) preferred the DRDR system, 13% (n = 22) preferred the system providing immediate results
(p textless .0001), and the other 19 respondents did not select a
preference. Of the 167 respondents, 156 answered the question regarding
previous screening mammography experience. Of the 105 patients who had undergone screening mammography at our institution, 78% (n =
82) preferred the DRDR system. Of the 51 patients who had undergone
mammography elsewhere or who had never undergone mammography, 75% (n = 38) preferred the DRDR system. We found that ordering of presentation
of the systems in the questionnaire had no effect on responses. Likewise,
whether a respondent had undergone mammography at our institution had no effect on responses (p = 1.0). CONCLUSION: A statistically
significant number of women who responded to our questionnaire preferred
the DRDR system of reporting screening mammographic results. Educational
material about double reading that we included with each patient's
questionnaire could account for these results. If the use of a second
interpreter is feasible and is done for batch interpretation of screening
mammograms, then education of patients about this process may increase
acceptance of a delayed mammographic report.
Goldberg, M. A.; Gazelle, G. Scott; Boland, G. W.; Hahn, P. F.; Mayo-Smith, W. W.; Pivovarov, M.; Halpern, Elkan F.; Wittenberg, J.
Focal hepatic lesions: effect of three-dimensional wavelet compression on detection at CT Journal Article
In: Radiology, vol. 202, pp. 159-65, 1997, ().
@article{Goldberg1997,
title = {Focal hepatic lesions: effect of three-dimensional wavelet compression on detection at CT},
author = {M. A. Goldberg and G. Scott Gazelle and G. W. Boland and P. F. Hahn and W. W. Mayo-Smith and M. Pivovarov and Elkan F. Halpern and J. Wittenberg},
url = {http://www.ncbi.nlm.nih.gov/pubmed/8988206},
year = {1997},
date = {1997-01-01},
journal = {Radiology},
volume = {202},
pages = {159-65},
abstract = {PURPOSE: To evaluate the effect of three-dimensional, wavelet-based
compression on the detection of focal hepatic lesions at computed
tomography (CT). MATERIALS AND METHODS: CT images obtained in 69
patients with focal hepatic lesions were studied (35 consecutive
cases and 34 cases selected to be difficult on the basis of lesion
size or contrast). Image data were compressed by means of a three-dimensional,
wavelet-based algorIthm at ratios of 10:1, 15:1, and 20:1. Normal
and abnormal sections (on original and compressed images) were reviewed
by using an interactive workstation. Four readers rated the presence
or absence of a lesion with a five-point scale. RESULTS: At receiver
operating characteristic analysis, no statistically significant difference
was detected for all cases considered together. Differences approached
but did not reach statistical significance for the diagnostic performance of one reader with compressed images (15:},
keywords = {},
pubstate = {published},
tppubtype = {article}
}
PURPOSE: To evaluate the effect of three-dimensional, wavelet-based
compression on the detection of focal hepatic lesions at computed
tomography (CT). MATERIALS AND METHODS: CT images obtained in 69
patients with focal hepatic lesions were studied (35 consecutive
cases and 34 cases selected to be difficult on the basis of lesion
size or contrast). Image data were compressed by means of a three-dimensional,
wavelet-based algorIthm at ratios of 10:1, 15:1, and 20:1. Normal
and abnormal sections (on original and compressed images) were reviewed
by using an interactive workstation. Four readers rated the presence
or absence of a lesion with a five-point scale. RESULTS: At receiver
operating characteristic analysis, no statistically significant difference
was detected for all cases considered together. Differences approached
but did not reach statistical significance for the diagnostic performance of one reader with compressed images (15:
compression on the detection of focal hepatic lesions at computed
tomography (CT). MATERIALS AND METHODS: CT images obtained in 69
patients with focal hepatic lesions were studied (35 consecutive
cases and 34 cases selected to be difficult on the basis of lesion
size or contrast). Image data were compressed by means of a three-dimensional,
wavelet-based algorIthm at ratios of 10:1, 15:1, and 20:1. Normal
and abnormal sections (on original and compressed images) were reviewed
by using an interactive workstation. Four readers rated the presence
or absence of a lesion with a five-point scale. RESULTS: At receiver
operating characteristic analysis, no statistically significant difference
was detected for all cases considered together. Differences approached
but did not reach statistical significance for the diagnostic performance of one reader with compressed images (15:
McDowell, R. K.; Gazelle, G. Scott; Murphy, B. L.; Boland, G. W.; Mayo-Smith, W. W.; Warshaw, A. L.; Mueller, P. R.
Mucinous ductal ectasia of the pancreas Journal Article
In: J Comput Assist Tomogr, vol. 21, no. 3, pp. 383-8, 1997, ISSN: 0363-8715 (Print) 0363-8715 (Lin, ().
@article{McDowell1997,
title = {Mucinous ductal ectasia of the pancreas},
author = {R. K. McDowell and G. Scott Gazelle and B. L. Murphy and G. W. Boland and W. W. Mayo-Smith and A. L. Warshaw and P. R. Mueller},
url = {http://www.ncbi.nlm.nih.gov/pubmed/9135644},
issn = {0363-8715 (Print) 0363-8715 (Lin},
year = {1997},
date = {1997-00-01},
journal = {J Comput Assist Tomogr},
volume = {21},
number = {3},
pages = {383-8},
abstract = {PURPOSE: Pancreatic mucinous ductal ectasia (MDE) is a recently described
and poorly understood disorder, with few cases reported in the imaging
literature. We undertook this study to describe the spectrum of CT
and pancreatographic findings of MDE and to investigate the incidence
of associated pancreatic malignancy. METHOD: The medical records,
CT scans, and pancreatograms of 12 consecutive patients with pathologically
proven MDE were retrospectively reviewed. There were nine men and
three women, ranging in age from 37 to 72 years (mean 59 years).
RESULTS: Focal lesions involved primarily the uncinate (two patients)
and head (eight patients) by CT imaging. The entire gland was involved
in two patients. CT findings were variable and included focal pancreatic
enlargement, a low attenuation or cystic mass, low attenuation of
the entire gland, or marked ductal dilatation. Pancreatographic findings
were more consistent, showing ductal dilatation with or without intraluminal
filling defects, obstruction, or displacement. In all cases, findings
at endoscopy were felt to be characteristic, with ductal dilatation,
filling defects, or abundant mucus seen upon cannulation of the pancreatic
duct. Carcinoma-in-situ was present in six cases, cellular atypia
without malignancy in two, and in three cases the lesions were histologically
benign. One case demonstrated invasive adenocarcinoma. No finding
or group of findings on CT or pancreatography permitted differentiation
between benign and malignant lesions. CONCLUSION: MDE can present
with a variety of appearances on CT, none of which is diagnostic.
Pancreatography can be diagnostic if dilatation and intraluminal
filling defects are seen. Carcinoma-in-situ, invasive adenocarcinoma,
or cellular atypia is present in approximately 75%, but cannot be
accurately diagnosed prospectively.},
keywords = {},
pubstate = {published},
tppubtype = {article}
}
PURPOSE: Pancreatic mucinous ductal ectasia (MDE) is a recently described
and poorly understood disorder, with few cases reported in the imaging
literature. We undertook this study to describe the spectrum of CT
and pancreatographic findings of MDE and to investigate the incidence
of associated pancreatic malignancy. METHOD: The medical records,
CT scans, and pancreatograms of 12 consecutive patients with pathologically
proven MDE were retrospectively reviewed. There were nine men and
three women, ranging in age from 37 to 72 years (mean 59 years).
RESULTS: Focal lesions involved primarily the uncinate (two patients)
and head (eight patients) by CT imaging. The entire gland was involved
in two patients. CT findings were variable and included focal pancreatic
enlargement, a low attenuation or cystic mass, low attenuation of
the entire gland, or marked ductal dilatation. Pancreatographic findings
were more consistent, showing ductal dilatation with or without intraluminal
filling defects, obstruction, or displacement. In all cases, findings
at endoscopy were felt to be characteristic, with ductal dilatation,
filling defects, or abundant mucus seen upon cannulation of the pancreatic
duct. Carcinoma-in-situ was present in six cases, cellular atypia
without malignancy in two, and in three cases the lesions were histologically
benign. One case demonstrated invasive adenocarcinoma. No finding
or group of findings on CT or pancreatography permitted differentiation
between benign and malignant lesions. CONCLUSION: MDE can present
with a variety of appearances on CT, none of which is diagnostic.
Pancreatography can be diagnostic if dilatation and intraluminal
filling defects are seen. Carcinoma-in-situ, invasive adenocarcinoma,
or cellular atypia is present in approximately 75%, but cannot be
accurately diagnosed prospectively.
and poorly understood disorder, with few cases reported in the imaging
literature. We undertook this study to describe the spectrum of CT
and pancreatographic findings of MDE and to investigate the incidence
of associated pancreatic malignancy. METHOD: The medical records,
CT scans, and pancreatograms of 12 consecutive patients with pathologically
proven MDE were retrospectively reviewed. There were nine men and
three women, ranging in age from 37 to 72 years (mean 59 years).
RESULTS: Focal lesions involved primarily the uncinate (two patients)
and head (eight patients) by CT imaging. The entire gland was involved
in two patients. CT findings were variable and included focal pancreatic
enlargement, a low attenuation or cystic mass, low attenuation of
the entire gland, or marked ductal dilatation. Pancreatographic findings
were more consistent, showing ductal dilatation with or without intraluminal
filling defects, obstruction, or displacement. In all cases, findings
at endoscopy were felt to be characteristic, with ductal dilatation,
filling defects, or abundant mucus seen upon cannulation of the pancreatic
duct. Carcinoma-in-situ was present in six cases, cellular atypia
without malignancy in two, and in three cases the lesions were histologically
benign. One case demonstrated invasive adenocarcinoma. No finding
or group of findings on CT or pancreatography permitted differentiation
between benign and malignant lesions. CONCLUSION: MDE can present
with a variety of appearances on CT, none of which is diagnostic.
Pancreatography can be diagnostic if dilatation and intraluminal
filling defects are seen. Carcinoma-in-situ, invasive adenocarcinoma,
or cellular atypia is present in approximately 75%, but cannot be
accurately diagnosed prospectively.
1996
Frayne, R.; Grist, T. M.; Korosec, F. R.; Willig, D. S.; Swan, J. Shannon; Turski, P. A.; Mistretta, C. A.
MR angiography with three-dimensional MR digital subtraction angiography Journal Article
In: Top Magn Reson Imaging, vol. 8, no. 6, pp. 366-88, 1996, ISSN: 0899-3459 (Print) 0899-3459 (Li, ().
@article{Frayne1996,
title = {MR angiography with three-dimensional MR digital subtraction angiography},
author = {R. Frayne and T. M. Grist and F. R. Korosec and D. S. Willig and J. Shannon Swan and P. A. Turski and C. A. Mistretta},
url = {https://www.ncbi.nlm.nih.gov/pubmed/9402678},
issn = {0899-3459 (Print)
0899-3459 (Li},
year = {1996},
date = {1996-01-01},
journal = {Top Magn Reson Imaging},
volume = {8},
number = {6},
pages = {366-88},
keywords = {},
pubstate = {published},
tppubtype = {article}
}
Grist, T. M.; Swan, J. Shannon; Korosec, F. R.
Investigators refine MR angio methods Journal Article
In: Diagn Imaging (San Franc), vol. 18, no. 4, pp. 45-50, 1996, ISSN: 0194-2514 (Print) 0194-2514 (Li, ().
@article{Grist1996,
title = {Investigators refine MR angio methods},
author = {T. M. Grist and J. Shannon Swan and F. R. Korosec},
url = {https://www.ncbi.nlm.nih.gov/pubmed/10159857},
issn = {0194-2514 (Print)
0194-2514 (Li},
year = {1996},
date = {1996-01-01},
journal = {Diagn Imaging (San Franc)},
volume = {18},
number = {4},
pages = {45-50},
keywords = {},
pubstate = {published},
tppubtype = {article}
}
Swan, J. Shannon
Intrapelvic two-dimensional time-of-flight magnetic resonance angiography in healthy and diseased subjects Journal Article
In: Acad Radiol, vol. 3, no. 7, pp. 607-9; discussion 60, 1996, ISSN: 1076-6332 (Print) 1076-6332 (Li, ().
@article{Swan1996,
title = {Intrapelvic two-dimensional time-of-flight magnetic resonance angiography in healthy and diseased subjects},
author = {J. Shannon Swan},
url = {https://www.ncbi.nlm.nih.gov/pubmed/8796723},
doi = {10.1016/s1076-6332(96)80227-3},
issn = {1076-6332 (Print)
1076-6332 (Li},
year = {1996},
date = {1996-01-01},
journal = {Acad Radiol},
volume = {3},
number = {7},
pages = {607-9; discussion 60},
keywords = {},
pubstate = {published},
tppubtype = {article}
}
1995
Alley, M. T.; Grist, T. M.; Swan, J. Shannon
Development of a phased-array coil for the lower extremities Journal Article
In: Magn Reson Med, vol. 34, no. 2, pp. 260-7, 1995, ISSN: 0740-3194 (Print) 0740-3194 (Li, ().
@article{Alley1995,
title = {Development of a phased-array coil for the lower extremities},
author = {M. T. Alley and T. M. Grist and J. Shannon Swan},
url = {https://www.ncbi.nlm.nih.gov/pubmed/7476086},
doi = {10.1002/mrm.1910340218},
issn = {0740-3194 (Print)
0740-3194 (Li},
year = {1995},
date = {1995-01-01},
journal = {Magn Reson Med},
volume = {34},
number = {2},
pages = {260-7},
keywords = {},
pubstate = {published},
tppubtype = {article}
}
Swan, J. Shannon; Grist, T. M.; Sproat, I. A.; Heiner, J. P.; Wiersma, S. R.; Heisey, D. M.
Musculoskeletal neoplasms: preoperative evaluation with MR angiography Journal Article
In: Radiology, vol. 194, no. 2, pp. 519-24, 1995, ISSN: 0033-8419 (Print) 0033-8419 (Li, ().
@article{Swan1995,
title = {Musculoskeletal neoplasms: preoperative evaluation with MR angiography},
author = {J. Shannon Swan and T. M. Grist and I. A. Sproat and J. P. Heiner and S. R. Wiersma and D. M. Heisey},
url = {https://www.ncbi.nlm.nih.gov/pubmed/7529935},
doi = {10.1148/radiology.194.2.7529935},
issn = {0033-8419 (Print)
0033-8419 (Li},
year = {1995},
date = {1995-01-01},
journal = {Radiology},
volume = {194},
number = {2},
pages = {519-24},
keywords = {},
pubstate = {published},
tppubtype = {article}
}
Swan, J. Shannon; Korosec, F. R.; Heisey, D. M.; Grist, T. M.
In: J Vasc Interv Radiol, vol. 6, no. 6, pp. 965-70, 1995, ISSN: 1051-0443 (Print) 1051-0443 (Li, ().
@article{Swan1995a,
title = {Evaluation of presaturation pulse thickness and gap for lower extremity peripheral two-dimensional time-of-flight MR angiography with a signa 1.5-T unit},
author = {J. Shannon Swan and F. R. Korosec and D. M. Heisey and T. M. Grist},
url = {https://www.ncbi.nlm.nih.gov/pubmed/8850678},
doi = {10.1016/s1051-0443(95)71223-4},
issn = {1051-0443 (Print)
1051-0443 (Li},
year = {1995},
date = {1995-01-01},
journal = {J Vasc Interv Radiol},
volume = {6},
number = {6},
pages = {965-70},
keywords = {},
pubstate = {published},
tppubtype = {article}
}
Tuite, M. J.; Smet, A. A. De; Swan, J. Shannon; Keene, J. S.
MR imaging of a meniscal ossicle Journal Article
In: Skeletal Radiol, vol. 24, no. 7, pp. 543-5, 1995, ISSN: 0364-2348 (Print)0364-2348 (Li, ().
@article{Tuite1995,
title = {MR imaging of a meniscal ossicle},
author = {M. J. Tuite and A. A. De Smet and J. Shannon Swan and J. S. Keene},
url = {https://www.ncbi.nlm.nih.gov/pubmed/8545656},
doi = {10.1007/BF00202157},
issn = {0364-2348 (Print)0364-2348 (Li},
year = {1995},
date = {1995-01-01},
journal = {Skeletal Radiol},
volume = {24},
number = {7},
pages = {543-5},
keywords = {},
pubstate = {published},
tppubtype = {article}
}
1994
Smet, A. A. De; Tuite, M. J.; Norris, M. A.; Swan, J. Shannon
MR diagnosis of meniscal tears: analysis of causes of errors Journal Article
In: AJR Am J Roentgenol, vol. 163, no. 6, pp. 1419-23, 1994, ISSN: 0361-803X (Print) 0361-803X (Li, ().
@article{DeSmet1994,
title = {MR diagnosis of meniscal tears: analysis of causes of errors},
author = {A. A. De Smet and M. J. Tuite and M. A. Norris and J. Shannon Swan},
url = {https://www.ncbi.nlm.nih.gov/pubmed/7992739},
doi = {10.2214/ajr.163.6.7992739},
issn = {0361-803X (Print)
0361-803X (Li},
year = {1994},
date = {1994-01-01},
journal = {AJR Am J Roentgenol},
volume = {163},
number = {6},
pages = {1419-23},
keywords = {},
pubstate = {published},
tppubtype = {article}
}
1993
Damron, T. A.; Brodke, D. S.; Heiner, J. P.; Swan, J. Shannon; DeSouky, S.
Case report 803: Gorham's disease (Gorham-Stout syndrome) of scapula Journal Article
In: Skeletal Radiol, vol. 22, no. 6, pp. 464-7, 1993, ISSN: 0364-2348 (Print) 0364-2348 (Li, ().
@article{Damron1993,
title = {Case report 803: Gorham's disease (Gorham-Stout syndrome) of scapula},
author = {T. A. Damron and D. S. Brodke and J. P. Heiner and J. Shannon Swan and S. DeSouky},
url = {https://www.ncbi.nlm.nih.gov/pubmed/8248825},
doi = {10.1007/BF00538454},
issn = {0364-2348 (Print)
0364-2348 (Li},
year = {1993},
date = {1993-01-01},
journal = {Skeletal Radiol},
volume = {22},
number = {6},
pages = {464-7},
keywords = {},
pubstate = {published},
tppubtype = {article}
}