笑い発作が改善した視床下部過誤腫の1手術例

A Successful Surgical Case of a Hypothalamic Hamartoma with Gelastic Seizure: A Case Report

Ⅰ．はじめに

　視床下部過誤腫は視床下部に発生する稀な疾患である．特に笑い発作を伴っている場合，放置すれば全般発作へ移行し，痙攣重責発作や知能発達障害などの原因にもなり得る．治療法に関しては従来の摘出術に加えガンマナイフや内視鏡使用などによるdisconnectionなどの報告は蓄積されてきているものの，症例数が少なく，外科的治療法選択に関してのプロトコルは未だ確立していない．今回，薬物療法に抵抗性で発作回数が増大する傾向にあった笑い発作を症状とするValduezaの分類でtypeⅡaの視床下部過誤腫で，開頭術によるdisconnectionが有効であった症例を経験したので，若干の文献的考察とともに報告する．

　Gelastic seizure is a rare form of epilepsy defined as automatic bouts of laughter without mirth commonly associated with a hypothalamic hamartoma. Surgical treatment of hypothalamic hamartomas is associated with a high risk of complications because of the close vicinity of adjacent structures such as the optic tracts and mammillary bodies. This case was an 11-year-old girl who presented with gelastic seizure and complicated partial seizure. She developed gelastic seizure at a frequency of 10 bouts per day. She was found to have an elliptical mass close to the left hypothalamus. The signal intensity on magnetic resonance imaging (MRI) was consistent with hypothalamic hamartoma. The patient underwent surgical resection by a subtemporal approach. Pathological findings confirmed the diagnosis of hypothalamic hamartoma. Postoperative MRI demonstrated that the hypothalamic hamartoma was successfully resected. Twenty four months after surgery, complicated partial seizure in this patient has improved to Engel's class Ia and gelastic seizure has improved to Engel's class Ⅲa.