有痛性痙攣性チック（Painful Tic Convulsif）の1例―発生機序の文献的考察

A Case of Painful Tic Convulsif : Discussion of the Underlying Mechanisms and Review of the Literature

　Ⅰ．はじめに

　片側顔面痙攣と同側の三叉神経痛が合併する病態は，有痛性痙攣性チック（painful tic convulsif:PTC）と呼ばれ，比較的稀と考えられている．われわれが渉猟し得た限りでは，これまで70の症例が報告されている^{1-12,14-17,19-30)}が，一般的な神経血管圧迫症候群と同様に，PTCにおいてもいまだ発症機序や病態については十分な解明がなされていない．今回，高度の椎骨脳底動脈の蛇行を呈するtortuous vertebrobasilar system（TVBS）に伴い，複数の独立した責任血管によりPTCを呈した症例を経験したので，若干の文献的考察を加え報告する．

　The combination of trigeminal neuralgia and ipsilateral hemifacial spasm,known as painful tic convulsif (PTC),is a relatively rare entity in neurovascular compression syndrome. A case of PTC attributable to different offending arteries is described,the mechanisms and characteristics of PTC are discussed,and a review of the literature is presented. This 80-year-old woman had a 10-year history of left trigeminal neuralgia and ipsilateral hemifacial spasm. She presented with intermittent left facial twitching and pain,especially upon swallowing. MRI revealed compression of the left trigeminal nerve by the left anterior inferior cerebellar artery and of the ipsilateral facial nerve by the posterior inferior cerebellar artery. Microvascular decompression of the lesions via left lateral suboccipital craniotomy resulted in immediate and complete symptom improvement. Our case demonstrates that different arteries can affect the trigeminal and facial nerve at a stage that precedes compression by a tortuous vertebrobasilar artery. We suggest that the presence of PTC should be considered in patients with a tortuous vertebrobasilar artery,irrespective of the offending arteries.