Search

Your search keyword '"Lewin, J S"' showing total 233 results
Start Over Author "Lewin, J S"
233 results on '"Lewin, J S"'

3. The Aortic Arch

Author

Lewin, J. S., Baert, A. L., editor, Heuck, F. H. W., editor, Youker, J. E., editor, Brady, L. W., editor, Heilmann, H.-P., editor, Arlart, Ingolf P., editor, Bongartz, Georg M., editor, and Marchal, Guy, editor

Published
1996
Full Text
View/download PDF

11. Sex and electroencephalographic synchronization after photic stimulation predict signal changes in the visual cortex on functional MR images

Author

Peter Hedera, Wu, D., Collins, S., Lewin, J. S., Miller, D., Lerner, A. J., Klein, S., and Friedland, R. P.

Subjects
genetic structures, Journal Article, sense organs
Abstract

PURPOSE: We evaluated factors that influence MR signal changes during photic stimulation of the visual cortex. We also tested the hypothesis that functional MR imaging response corresponds to electroencephalographic (EEG) synchronization after photic stimulation. METHODS: Thirty-eight healthy subjects, 20 men and 18 women, underwent photic stimulation of the visual cortex. They were studied with a 1.5-T MR unit, and photic stimulation was induced via 8-Hz LED goggles. Seven subjects with and seven without detectable functional MR imaging response to photic stimulation underwent further studies with 16-channel EEG after 2- to 30-Hz stroboscopic stimulation. RESULTS: Thirteen men and 18 women had a significant increase in MR signal in the visual cortex; seven men showed no visual cortex activation during more than two repeated studies. Six of seven volunteers with increased functional MR imaging signal after photic stimulation also showed signs of EEG synchronization when an 8-Hz stroboscopic flash was used; six of seven subjects with no functional MR imaging lacked EEG synchronization at 8-Hz stimulation. CONCLUSIONS: Men were more likely than women to have undetectable MR signal changes after photic stimulation. This finding should be considered when interpreting results of functional MR imaging studies. EEG with stroboscopic examination is a good predictor of functional MR imaging sensitivity to changes in regional cerebral blood flow induced by sensory stimulation.

Published
1998

12. Malignant hemangioendothelioma (angiosarcoma) of the skull: plain film, CT, and MR appearance

Author

Bourekas, E C, Cohen, M L, Kamen, C S, Tarr, R W, Lanzieri, C F, and Lewin, J S

Subjects
Male, stomatognathic diseases, Adolescent, Hemangiosarcoma, Skull, Skull Neoplasms, Humans, Case Reports, Tomography, X-Ray Computed, Magnetic Resonance Imaging
Abstract

Hemangioendothelioma is a rare neoplasm of bone that uncommonly involves the skull. We present a case of grade III malignant hemangioendothelioma (also known as angiosarcoma) of the skull in a 13-year-old boy and describe the plain film, CT, and MR appearance of this neoplasm as well as its histopathology.

Published
1996

13. Aggressive fibromatosis of the prevertebral and retropharyngeal spaces: MR and CT characteristics

Author

Lewin, J S and Lavertu, P

Subjects
Gadolinium DTPA, Male, Spinal Neoplasms, Contrast Media, Pharyngeal Neoplasms, Case Reports, Fibroma, Middle Aged, Pentetic Acid, Magnetic Resonance Imaging, Diagnosis, Differential, Drug Combinations, Meglumine, Head and Neck Neoplasms, Neck Muscles, Cervical Vertebrae, Organometallic Compounds, Humans, Tomography, X-Ray Computed
Abstract

A 47-year-old man had aggressive fibromatosis, and CT and MR showed a large, multilobulated soft-tissue mass within the prevertebral and retropharyngeal spaces. On CT, the lesion was slightly higher in attenuation than adjacent muscle; on MR, it was intermediate between muscle and fat on unenhanced T1-weighted images, isointense with fat on intermediate-weighted images, hyperintense relative to fat on T2-weighted images, and markedly enhanced after administration of gadopentetate dimeglumine. Multiple small focal and linear areas of decreased signal intensity that did not enhance with gadopentetate dimeglumine were observed on all pulse sequences.

Published
1995

25. Metastases to the pancreas.

Author

Merkle, E M, primary, Boaz, T, additional, Kolokythas, O, additional, Haaga, J R, additional, Lewin, J S, additional, and Brambs, H J, additional

Published
1998
Full Text
View/download PDF

33. Papillary endolymphatic sac tumors: CT, MR imaging, and angiographic findings in 20 patients.

Author

Mukherji, S K, primary, Albernaz, V S, additional, Lo, W W, additional, Gaffey, M J, additional, Megerian, C A, additional, Feghali, J G, additional, Brook, A, additional, Lewin, J S, additional, Lanzieri, C F, additional, Talbot, J M, additional, Meyer, J R, additional, Carmody, R F, additional, Weissman, J L, additional, Smirniotopoulos, J G, additional, Rao, V M, additional, Jinkins, J R, additional, and Castillo, M, additional

Published
1997
Full Text
View/download PDF

41. 2D and 3D high resolution gradient echo functional imaging of the brain: Venous contributions to signal in motor cortex studies

Author

Haacke, E. M., primary, Hopkins, A., additional, Lai, S., additional, Buckley, P., additional, Friedman, L., additional, Meltzer, H., additional, Hedera, P., additional, Friedland, R., additional, Klein, S., additional, Thompson, L., additional, Detterman, D., additional, Tkach, J., additional, and Lewin, J. S., additional

Published
1994
Full Text
View/download PDF

44. MR imaging-guided radiofrequency thermal ablation in the porcine brain at 0.2 T.

Author

Merkle, Elmar M., Shonk, Jason R., Zheng, Lan., Duerk, Jeffrey L., Lewin, Jonathan S., Merkle, E M, Shonk, J R, Zheng, L, Duerk, J L, and Lewin, J S

Subjects
MAGNETIC resonance imaging, RADIO frequency, ABLATION techniques, PORCINE somatotropin, SOMATOTROPIN, SWINE growth
Abstract

The aim of this study was to test the hypotheses that (a) MR imaging-guided radiofrequency (RF) thermal ablation is safe and feasible in porcine brain using an open C-arm-shaped low-field MR system, and that (b) induced thermal lesion size can be predicted using low-field MR imaging. Magnetic resonance-guided RF ablation was performed in the cerebral frontal lobes of six pigs. An 18-G monopolar RF electrode was inserted into the porcine brain using MR image guidance and RF was then applied for 10 min. After post-procedure imaging (T2-weighted, T1-weighted before and after gadodiamide administration), the pigs were killed and the brains were used for pathologic examination. Successful RF electrode placement was accomplished in all cases without complications; total magnet time ranged from 73 to 189 min. The thermal lesion size varied from 10 to 12 mm perpendicular to the electrode track and was easily visualized on T2-weighted and enhanced T1-weighted images. Enhanced T1-weighted imaging demonstrated the highest brain-to-RF thermal lesion contrast-to-noise ratio with an average of 1.5 +/- 1.6. Enhanced T1-weighted imaging never underestimated pathologic lesion diameter with a mean difference of 2.3 +/- 1.0 mm and a radiologic/pathologic correlation of 0.69. Magnetic resonance imaging-guided RF thermal ablation is feasible and safe in the porcine brain using an open MR low-field system. Induced-thermal lesion size can best be monitored using enhanced T1-weighted images. In the future, RF ablation under low-field MR guidance may offer an alternative treatment option for primary and secondary brain tumors. [ABSTRACT FROM AUTHOR]

Published
2001
Full Text
View/download PDF

Catalog

Books, media, physical & digital resources
See catalog results