三叉神经脑池段的扩散张量成像观测及临床应用

目的为三叉神经痛的临床诊断提供微细结构变化的影像依据。方法选取颅脑部扩散张量成像(DTI)扫描检查正常者150例和原发性单侧三叉神经痛患者100例,按照病变程度分为A组(接近或接触组)、B组(轻度压迫组)、C组(重度压迫组)、D组(压迫变形且萎缩组),在工作站划分三叉神经脑池段和三叉神经痛病变部位的感兴趣区,测量感兴趣区的表观扩散系数(ADC)和各向异性分数(FA)。比较三叉神经脑池段不同年龄、部位和三叉神经痛患侧、健侧及不同病变程度的ADC值和FA值。结果35岁以下组、35~55岁组、55岁以上组的三叉神经脑池段,除距离脑干6mm、9mm处的ADC值外,其他ADC值和FA值均无统计学差异(P>0.05)。三叉神经脑池段距离脑干0、3、6、9mm处,除6mm、9mm处的FA值外,其他FA值和ADC值均有统计学差异(P<0.05)。三叉神经痛患侧组与健侧组、正常组的ADC值和FA值均有统计学差异(P<0.05),健侧组与正常组的ADC值和FA值无统计学差异(P>0.05)。三叉神经痛患侧A组、B组、C组、D组的ADC值和FA值均有统计学差异(P<0.05)。结论三叉神经脑池段的ADC值和FA值与年龄、部位及三叉神经痛的患侧受血管压迫程度等密切相关,DTI为三叉神经脑池段的微细结构变化提供了客观影像诊断依据。

Diffusion tensor imaging observation and clinical application of the cisternal segment of trigeminalnerve

Objective　To provide the imaging basis on microstructure changing for the clinical diagnosis of trigeminal neuralgia.　Methods　There were 150 normal persons and 100 patients with primary trigeminal neuralgia selected by diffusion tensor imaging (DTI) scanning of the cranial brain, and all patients were unilateral. The patients were divided into group A (close or contact group), group B (mild compression group), group C (severe compression group) and group D (compression deformation and atrophy group) according to the degree of lesion. The region of interest was divided into the cisternal segment of trigeminal nerve and the lesion site of trigeminal neuralgia at workstation, and the apparent diffusion coefficient (ADC) value and fractional anisotropy (FA) value of the region of interest were measured. ADC values and FA values of different ages, sites, the affected and healthy sides of trigeminal neuralgia, and different lesions of the trigeminal cerebral cistern were compared.　Results　There was no statistical differences in other ADC values and FA values between the groups under 35 years old, 35~55 years old and over 55 years old except the ADC value at 6 mm and 9 mm from the brainstem (P＞0.05). Apart from the FA values at 6 mm and 9 mm, statistical differences in other FA values and ADC values between the 0 mm, 3 mm, 6 mm and 9 mm length from brainstem of the cisternal segment of trigeminal nerve were found (P＜0.05). statistical differences in the ADC values and FA values among the affected-side group, the healthy-side group of trigeminal neuralgia and the normal group were found(P＜0.05), and no statistical difference in ADC values and FA values between the healthy-side group of trigeminal neuralgia and normal group was found (P＞0.05). Statistical differences in ADC values and FA values among the A, B, C and D groups on the affected side of trigeminal neuralgia were found (P＜0.05).　Conclusions　The ADC values and FA values of the cisternal segment of trigeminal nerve are closely related to the age, position and the degree of vascular compression on the affected side of trigeminal neuralgia. DTI can provide an objective imaging diagnostic basis for the changes in the microstructure of the trigeminal cistern.