Filippi M, Rocca M A, Wiessmann M, Mennea S, Cercignani M, Yousry T A, Sormani M P, Comi G
Department of Neuroscience, Scientific Institute Ospedale San Raffaele, University of Milan, Italy.
AJNR Am J Neuroradiol. 1999 Nov-Dec;20(10):1931-8.
Fast fluid-attenuated inversion-recovery (FLAIR) sequences are sensitive for detecting lesions in patients with multiple sclerosis (MS). More rapid fast-FLAIR imaging of the brain can be achieved by the concomitant use of half-Fourier acquisition single-shot turbo spin-echo (HASTE-FLAIR) and echo-planar imaging (EPI-FLAIR). The present study was performed in a large cohort of subjects to assess and compare the number and volume of brain lesions detected by the fast-FLAIR, HASTE-FLAIR, and EPI-FLAIR sequences in patients with MS.
Fast-FLAIR, HASTE-FLAIR, and EPI-FLAIR sequences were obtained from 46 consecutive MS patients. Lesions seen on each type of sequence were counted and classified by consensus by two observers. Lesion volumes were measured using a semiautomated segmentation technique based on local thresholding.
The quality of the fast-FLAIR images was significantly better than that of HASTE-FLAIR and EPI-FLAIR images. Fast-FLAIR revealed significantly more lesions and higher lesion volumes than did HASTE-FLAIR and EPI-FLAIR. A similar number of large lesions was detected by the three sequences, but HASTE-FLAIR and EPI-FLAIR showed significantly fewer small and intermediate lesions than did fast-FLAIR. The number of lesions seen on HASTE-FLAIR and EPI-FLAIR images was similar.
HASTE-FLAIR and EPI-FLAIR sequences revealed as many large MS lesions as fast-FLAIR. Because their acquisition times are only a fraction of that needed for fast-FLAIR sequences, they may be useful for making a rapid diagnosis of MS in uncooperative patients. Their reduced ability to detect smaller lesions indicates that they should not be used as a routine approach to imaging patients with MS.
快速液体衰减反转恢复（FLAIR）序列对检测多发性硬化症（MS）患者的病灶很敏感。通过同时使用半傅里叶采集单次激发快速自旋回波（HASTE-FLAIR）和平面回波成像（EPI-FLAIR），可以实现更快速的脑部快速FLAIR成像。本研究在一大群受试者中进行，以评估和比较MS患者中快速FLAIR、HASTE-FLAIR和EPI-FLAIR序列检测到的脑病灶数量和体积。
对46例连续的MS患者进行快速FLAIR、HASTE-FLAIR和EPI-FLAIR序列检查。由两名观察者通过共识对每种序列上看到的病灶进行计数和分类。使用基于局部阈值的半自动分割技术测量病灶体积。
快速FLAIR图像的质量明显优于HASTE-FLAIR和EPI-FLAIR图像。与HASTE-FLAIR和EPI-FLAIR相比，快速FLAIR显示出明显更多的病灶和更大的病灶体积。三种序列检测到的大病灶数量相似，但与快速FLAIR相比，HASTE-FLAIR和EPI-FLAIR显示出的小病灶和中等病灶明显更少。HASTE-FLAIR和EPI-FLAIR图像上看到的病灶数量相似。
HASTE-FLAIR和EPI-FLAIR序列检测到的大MS病灶与快速FLAIR一样多。由于它们的采集时间仅为快速FLAIR序列所需时间的一小部分，因此它们可能有助于对不合作的患者进行MS的快速诊断。它们检测较小病灶的能力降低表明，它们不应作为MS患者成像的常规方法。
