应用MRI海马体积测量评价颞叶癫痫、局灶性颞叶外癫癎和原发性癫痫大发作

MRI Hippocampal Volumetry in Temporal,Extratemporal and Idiopathic Generalized Epilepsy

目的:应用MRI体积测量评价颞叶癫癎、局灶性颞叶外癫癎和原发性癫癎大发作患者的海马体积改变,探讨海马硬化与癫癎发作的关系。材料和方法:74例癫癎患者和30例健康志愿者为研究对象,其中50例颞叶癫癎手术病理证实为海马硬化,6例局灶性颞叶外癫癎为临床诊断和证实,其余18例为原发性癫癎大发作。三组病例的平均病程无明显统计学差异。以正常对照组双侧海马体积的平均值减2倍标准差作为正常下限值来判断病例组双侧海马的绝对体积是否异常,绝对体积行标化处理。结果:50例颞叶癫癎患者中,33例(66%)的病侧海马体积小于正常,其中10例(20%)的对侧海马体积也小于正常。在6例局灶性颞叶外癫癎和18例癫癎大发作患者中,所有病例的双侧海马体积均在正常范围内。结论:颞叶癫癎具有特殊的病理改变,而有别于局灶性颞叶外癫癎和原发性癫癎大发作。MRI海马体积测量对探讨海马硬化与癫癎发作的关系具有很好的研究价值。

Purpose： To evaluate the hippocampal volumetric changes in temporal, extratemporal and idiopathic generalized epilepsy using MRI volumetry, and to explore the relationship between hippocampal sclerosis and epileptic seizure. Materials and Methods： Seventy-four epileptic patients and 30 healthy volunteers were studied by using MRI vohimetry of hippocampal formation （HF）. Fifty patients with intractable temporal lobe epilepsy（TLE） were verified as hippocampal sclerosis by operation and pathology, 6 patients had focal extratemporal lobe epilepsy, and 18 had idiopathic generalized epilepsy. The mean seizure duration among three groups had no significant difference. The mean value of normal hippocampal volume minus two times the standard deviation was set as the normal lower limit to evaluate whether the absolute volume of HF was abnormal or not. The absolute volume was normalized. Results： Among the 50 TLE patients, 33 （66%） had significant small HF volume ipsilateral to the operated side. Among them, 10 （20%） also had significant small HF volume on the contralateral side. While among the 6 patients with focal extratemporal lobe epilepsy and 18 with idiopathic generalized epilepsy, all the volumes of HF were beyond the normal lower limit. No significant smallness was demonstrated in them. Conclusion： TLE had special pathology substrate which is different from focal extratemporal lobe epilepsy and idiopathic generalized epilepsy. MRI hippocampal volumetry can help to explore the rela- tionship between hippocampal sclerosis and epileptic seizure.