伴少突胶质细胞增生的轻微皮质发育畸形:一种新的额叶癫痫病理类型

Mild malformation of cortical development with oligodendroglial hyperplasia:a new pathologicalsubtype of frontal lobe epilepsy

目的通过对1例病理诊断为伴少突胶质细胞增生的轻微皮质发育畸形的额叶癫痫的报道,分析其临床和病理特征,提高对这一新的癫痫病理诊断的认识。方法收集2016年3月就诊于北京协和医院神经科的1例临床表现为额叶癫痫患者的临床资料,总结其影像学和电生理特征及手术切除后病理形态和免疫组织化学染色特征,并与国际文献报道的相关病例和病理改变进行对比。结果患者女性,16岁,癫痫病程12年,临床表现为发作性愣神伴手部摸索和发声,约10次/d,有时表现为全身强直阵挛发作,予多种药物治疗效果均不佳,MRI提示左侧额叶眶额回皮质白质分界欠清,脑电图提示左额叶起源,行左侧前额叶切除术,病理提示额叶皮质神经元构造正常,部分区域灰白质界限不清,皮质下白质内可见片状少突胶质细胞增生,密度明显高于深部白质,增生区白质内异位神经元明显多于深部白质。免疫组织化学:增生细胞Olig-2(+),Ki-67个别(+),阳性率高于深部白质。术后2年随访患者病情稳定,未见颅内新发病灶。结论年轻患者额叶癫痫可存在经典皮质发育不良以外的特殊病理改变,癫痫的病理改变可能不仅仅局限于皮质,白质病理改变对癫痫发病的作用机制尚有待于进一步研究。

Objective To analyze the clinical and histology characteristics of a patient with frontal lobe epilepsy diagnosed with mild malformation of cortical development with oligodendroglial hyperplasia, and to recognize the new neuropathological entity.Methods Clinical history,seizure types,neuroimaging, electroencephalography as well as macroscope,histology and immunohistochemistry characteristics were collected from a frontal lobe epilepsy patient and were compared with cases from literature.Results It was a female patient aged 16 years with 12 years history of epilepsy.The seizures manifested as episodes of conscious loss with automatism including grope and voice lasting for seconds.About 10 episodes a day were found and sometimes with secondary generalized tonic-clonic seizures.MRI showed blurring of grey-white matter interface in left orbital frontal cortex.Video-encephalography revealed left frontal lobe origin of seizures.So left prefrontal lobe was removed.Histology showed almost normal cortex neuropil and neurons.Blurring of grey-white interface in some area with patches of proliferation of oligodendrocytes in the corresponding subcortical white matter was found.The density of oligodendrocytes was significantly higher in sub-cortical than in deep white matter both shown in HE and Oligo-2 staining.Obvious oligodendrocytes increase and satellite phenomenon in deep cortical layer as well as increased ectopic neurons in sub-cortical white matter werefound in the lesion.In proliferation area,there were some nuclei stained with Ki-67,but not as high as tumor. Subsequent follow up for two years proved the operation efficacy and benign prognosis.Conclusions There are special and undiscovered histopathological entities in epilepsy etiology.Although known as grey matter disease,white matter pathology plays an important role in epilepsy pathophysiology which needs further research.