超高场强磁共振扩散张量成像对脑白质疏松症的诊断价值

目的探讨超高场强磁共振扩散张量成像(DTI)对老年脑白质疏松症(LA)的诊断价值。方法单纯老年LA患者68例,应用超高场强3.0T磁共振行常规MRI及DTI检查,根据脑室周围高信号(PVH)分型,分别于侧脑室前角、后角周围脑白质及半卵圆中心测量脑白质病灶的平均扩散系数(ADC)和部分各向异性分数(FA)值,并进行统计分析。结果 68例老年中,PVH 1型42例,2型18例,3型6例,4型2例。随着PVH分型级别越高,ADC值越高,FA值越低(P<0.05,P<0.01),PVH与ADC值呈正相关(r=0.7328,P<0.01),与FA值呈负相关(r=-0.5816,P<0.01)。LA病灶在侧脑室前角、后角周围白质区和半卵圆中心区的ADC值逐渐升高,FA值则逐渐降低,差异有统计学意义(P<0.05)。结论应用超高场强DTI技术,可在特定脑白质病变区域通过更为准确的量化指标辅助临床对老年LA进行定性及定量的诊断。

Evaluation of uitra-high field MR diffusion tensor imaging in diagnosis of leukoaraiosis

Objective To study the role of 3.OT MR diffusion tensor imaging(DTI) in diagnosis of leukoaraiosis(LA).Methods Sixty-eight LA patients underwent 3.0 T conventional MRI and DTI.Average diffusion coefficient(ADC) and fractional anisotropy(FA) values of LA lesions, measured at the anterior and posterior horns of lateral ventricle and at the half-oval center,were compared and analyzed.Results Of the 68 elderly LA patients,42,18,6 and 2 were diagnosed with type 1 periventricular hyperintensity(PVH D.type 2 PVFKPVH 2),type 3 PVH(PVH 3) and type 4 PVH(PVH 4),respectively.The PVH was positively related with the ADC(r = 0.7328,P<0.01)and negatively related with the FA values(r=-0.5816,P<0.01).The ADC values were higher than the FA values measured at the anterior and posterior horn of lateral ventricle and at the half-oval center for the LA lesions(P<0.05).Conclusion Ultra-high field MR DTI,as a more accurate quantitative indication for specific LA lesions,can contribute to the qualitative and quantitative diagnosis of LA in elderly subjects.