TY - JOUR T1 - Comparison of lesion enhancement on spin-echo and gradient-echo images. JF - American Journal of Neuroradiology JO - Am. J. Neuroradiol. SP - 37 LP - 44 VL - 15 IS - 1 AU - P M Chappell AU - N J Pelc AU - T K Foo AU - G H Glover AU - S P Haros AU - D R Enzmann Y1 - 1994/01/01 UR - http://www.ajnr.org/content/15/1/37.abstract N2 - 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 < .05) and greater contrast to noise (P < .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. ER -