常规磁共振与FLAIR序列对多发性硬化诊断的对比研究

A Comparative Study on the Efficacy of Routine MRI and FLAIR Sequence in the Diagnosis of Multiple Sclerosis

目的比较常规磁共振(MRI)检查和快速液体衰减翻转恢复序列(FLAIR)技术对颅脑多发性硬化症(MS)的诊断价值。方法采用美国GE公司生产的Signa 1.5T Twin Speed磁共振机,对58例经临床与实验室检查明确的MS病例(男34例、女24例,平均年龄35.95岁);例行T1FLAIR、T2WI及FLAIR技术检查,并对所检病灶进行对比。结果(1)FLAIR成像技术共检出病灶877个,T1FLAIR捡出病灶651个,为FLAIR序列总数的74%;T2加权成像检出病灶776个,为FLAIR序列总数的88%;对脑室周围及皮髓交界处病灶的检出率FLAIR序列明显优于T1FLAIR及T2WI。(2)MS病灶主要分布在脑室周围白质和半卵元中心区,两处病灶占总病灶数的96.1%。(3)病灶形态多为斑片状、圆形及/或卵圆形,也有少部分可见大片状病灶,甚至有的表现为假瘤样病灶。病灶的直径多小于1.5 cm。结论FLAIR序列对诊断MS优于T1FLAIR、T2WI,其发现MS病灶明显多于后者,且重复性好,能较好的显示近皮层处和脑室旁等传统T2易漏诊病灶,尤其对小病灶显示情况明显优于T1FLAIR、T2WI。

Objective To compare the efficacy of routine magnetic resonance imaging （MRI） to that of fluid-attenuated inversion recovery （FLAIR） sequence in the detection of lesions in patients with multiple sclerosis （MS）. Methods （1） Device： Signa 1.5T Twin Speed MRI scanner from General Electric, USA; （2）Cases： 58 patients with multiple sclerosis confirmed by clinical manifestation and laboratory exam, including 34 males and 24 females （mean age： 35.95）, were examined by MRI with T1FLAIR, T2-weighted imaging （T2WI） and FLAIR sequences and the lesion detectability by each of the sequences were compared. Results （1）A total of 877 lesions were found using FLAIR sequence, while 651 and 776 lesions were found with the T1 FLAIR and T2-weighted imaging （T2 WI）. The lesions detected by T1 FLAIR and T2 WI were 74% and 88%, respectively, of those detected by FLAIR sequence. FLAIR sequence was of greater value than T1 FLAIR and T2-weighted imaging in the detection of the periventricular lesions and lesions locating in the cortico-medullary junction; （2） The majority of the lesions distributed in the periventricular and centrum ovale white matter, which account for 96.1% of the lesions detected; （3） The lesions displayed in shape of plaque, spherical, ovale and, in rare cases, massive plaque and pseudoneoplasm, most of which were 〈1.5 cm in diameter. Conclusion FLAIR sequence outweighs T1 FLAIR and T2WI in the diagnosis of multiple sclerosis. With the FLAIR sequence, 23 % and 10% more lesions were detected than with T1 FLAIR and T2 WI, respectively. FLAIR is useful in the detection of lesions within juxtacortical and periventricular region which are readily be missed by routine T2 WI, and is especially advantageous in finding relatively small lesions.