海马硬化MR质子波谱分析与MRI的对比研究

目的　评价MR质子波谱分析 (1HMRS)和MRI对海马硬化的诊断价值。方法　对 8例病理证实的海马硬化病人和 8例健康志愿者分别进行1HMRS和MRI海马体积定量研究。通过计算峰下面积 ,对代谢产物氮 乙酰天门冬氨酸 (NAA)、肌酸 (Cr)及胆碱复合物 (Cho)的浓度进行定量并观察NAA/Cr、NAA/ (Cr Cho)及Cho/Cr各参数的变化 ,同时用右侧海马体积和左侧海马体积差值(DHF)的方法分析形态学的异常。结果　病变组病侧NAA/Cr、NAA/ (Cr Cho)及Cho/Cr值分别为0 5 5、1 77及 1 38,对照组分别为 0 77、1 38及 1 0 6。海马硬化病人NAA/Cr和NAA/ (Cr Cho)值下降 ,统计学上差异有显著性意义 (t值分别为 2 15和 4 83,P值均 <0 0 5 ) ,Cho/Cr值升高 ,统计学上差异有显著性意义 (t值为 2 34 ,P <0 0 5 )。根据NAA/ (Cr Cho)值的不对称降低可对 6例病人进行定侧诊断 ,其中错误 1例 ;根据DHF值的变化可诊断海马萎缩 2例。所有病例均经手术病理证实为海马硬化 ,病变程度与NAA/ (Cr Cho)值的降低相一致。NAA/ (Cr Cho)减低与癫痫发作次数无相关性 (r=- 0 134 ,P >0 0 5 )。结论　1HMRS能够早期发现海马硬化。1HMRS和MRI互相补充有利于海马硬化的术前诊断。

Studies on hippocampal sclerosis by ~1H MRS and MRI

Objective To determine the relative utility of 1H MRS and MRI for presurgical diagnosis of hippocampal sclerosis by the study on metabolic abnormalities and anatomical alterations in the brain of patients with temporal lobe epilepsy (TLE). Methods 1H MRS and MRI were performed on 8 patients with pathologically confirmed hippocampal sclerosis and 8 healthy volunteers on 2.0 T 1H MRS/MRI system. The values of NAA, Cr and Cho were calculated by integration of their peaks and the ratios of NAA/Cr, NAA/(Cr Cho), and Cho/Cr were measured. The volumes of both hippocampal formations in every case were observed and the differences of hippocampal formation (DHF) were analyzed. Results The ratios of NAA/Cr, NAA/(Cr Cho), and Cho/Cr in ipsilateral side were 0.55, 1.77, and 1.38, and in control subjects were 0.77, 1.38, and 1.06 separately. The ratios of NAA/Cr and NAA/(Cr Cho) were decreased on ipsilateral side (t=2.15, 4.83 separately, P<0.05), and the ratio of Cho/Cr was increased on ipsilateral side (t=2.34, P<0.05). Based on the value of NAA/(Cr Cho), six cases were lateralized with one case incorrect, and five cases showing bilateral abnormal. According to the value of DHF, two cases showed hippocampal atrophy. Therefore, by the combination of 1H MRS and MRI, seven of eight cases could be lateralized. Conclusion 1H MRS is sensitive to the diagnosis of neuron abnormality and coincident well with the pathological results. 1H MRS and MRI correctly lateralize most patients with hippocampal sclerosis and complement each other in final lateralization. The combination of 1H MRS and MRI can provide useful information for presurgical diagnosis of hippocampal sclerosis.