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PT  - JOURNAL ARTICLE
AU  - Chappell, P M
AU  - Pelc, N J
AU  - Foo, T K
AU  - Glover, G H
AU  - Haros, S P
AU  - Enzmann, D R
TI  - Comparison of lesion enhancement on spin-echo and gradient-echo images.
DP  - 1994 Jan 01
TA  - American Journal of Neuroradiology
PG  - 37--44
VI  - 15
IP  - 1
4099  - http://www.ajnr.org/content/15/1/37.short
4100  - http://www.ajnr.org/content/15/1/37.full
SO  - Am. J. Neuroradiol.1994 Jan 01; 15
AB  - PURPOSE To compare lesion enhancement after injection of gadopentetate dimeglumine on spin-echo and gradient-echo T1-weighted images. METHODS A total of 48 contrast-enhancing intracranial lesions were evaluated using a spin-echo and two gradient-echo T1-weighted pulse sequences. Percent contrast, contrast-to-noise, and signal-to-noise measurements were made on the spin-echo T1-weighted, three-dimensional gradient-echo, and multiplanar gradient-echo sequences. RESULTS The measurements were somewhat different for the following categories of lesions: extraaxial, intraaxial with edema, and intraaxial without edema. The latter group provided the greatest diagnostic challenge: three of 19 such lesions 1 cm in size or smaller could not be identified on three-dimensional gradient-echo images, and one could not be identified on multi-planar gradient-echo images. The spin-echo T1-weighted sequence demonstrated significantly higher percent contrast (P &amp;lt; .05) and greater contrast to noise (P &amp;lt; .03) than either gradient-echo sequence for these small intraaxial lesions without edema. For extraaxial and intraaxial lesions with edema, percent C was similar for spin-echo T1-weighted and three-dimensional gradient-echo images, while contrast to noise was greater for spin-echo T1-weighted images. This reflected greater tissue noise with gradient-echo sequences. CONCLUSION The T1-weighted spin-echo sequence was preferred for detecting the full spectrum of contrast-enhancing lesions of the central nervous system.