L-Dopaが著効を示した強迫笑いの1例—TRHならびにL-Dopa負荷試験による検討

A Case of Forced Laughing Improved by L-Dopa with Specia Reference to L-Dopa and TRH Test

I．はじめに

　強迫笑いとは，周囲の状況や刺激の大きさに不釣合で，本人にとっても感情にそぐわないような自動症的，絞切り型の笑いと定義され，種々の脳器質性疾患に出現するとされている。

　最近，われわれは，多発性脳梗塞により強迫笑いを呈し，L-Dopaが著効を示した症例を経験し，その際TRH負荷テスト，L-Dopa負荷テストを施行し，興味ある結果を得たので報告する。

　A case of forced laughing was reported. A 60-year-old woman was admitted to Department of Neuropsychiatry of Osaka Medical College with complaint of laughing without intention. Neurological evaluation at admission revealed pseudo-bulbar palsy, right mild hemiparesis, and mild left hypesthesia. Mood change or dementia was not present. On CT findings small hypodense lesions were found in bilateral thalamus, internal capsule, and corona radiata. According to Ironside this forced laughing was thought to be caused by either diencephalic level or bilateral corticobulbar level. Forced laughing occurred more than 10 times a day. L-Dopa from 150 mg to 250 mg per day was administered. After administration of L-Dopa forced laughing was prominently decreased and completely extin-guished after 2 months. In this case neuroendo-crinological camment was attempted.