磁共振弥散张量成像对Wallerian变性诊断价值的评价

Role of diffusion tensor imaging in diagnosing Wallerian degeneration

目的:探讨磁共振弥散张量成像技术(diffusion tensor imaging,DTI)在Wallerian变性中的诊断价值。方法:对40例正常志愿者、10例正常变异者和40例病变者分别进行DTI和常规MRI扫描。结果:正常志愿者大脑脚、脑桥基底部皮质脊髓束走行区各向异性分数(fractional anisotropy,FA)均值分别为0.73和0.63,其FA比值(数值小的一侧比大的一侧)分别为97.6%和96.8%;正常变异者大脑脚、脑桥基底部皮质脊髓束走行区FA均值分别为0.72和0.64,其FA值比值分别为96%和95%,与正常志愿者相比,差异无统计学意义(P>0.05);病变者患侧大脑脚、脑桥基底部FA均值分别为0.64及0.52。其FA比值(患侧FA值比健侧FA值)分别为76.0%和77.0%,患侧大脑脚、脑桥基底部皮质脊髓束的FA值及其比值较正常者明显减小,差异有统计学意义(P<0.05)。结论:DTI技术通过测量FA值及其比值及神经纤维束的三维重建,较常规MRI更为准确客观地诊断Wallerian变性。

Objective： To explore the value of the diffusion tensor imaging （DTI） in diagnosing Wallerian degeneration. Methods： DTI and MRI protocols were performed on 40 healthy volunteers, 10 normal variants and 40 patients, respectively. Results： The mean FA ratios of the corticospinal tracts in cerebral peduncle and basilar part of pons were 0.73 （97.6%） and 0.63 （96.8%） in 40 healthy volunteers, and they were 0.72 （96.0%） and 0.64 （95.0%） in 10 normal variants; No significant difference was found between the healthy volunteers and normal variants （P 〉0.05）. Whereas, they were 0.64（77.0%） and 0.52（76.0%） in40 patients, significantly reduced compared with the healthy volunteers and the normal variants（ P 〈 0.05）. Conclusion： DTI is more accurate than MRI in diagnosing Wallerian degeneration.