Cowden病に合併した耳下腺AVMの1例

A Case of Arteriovenous Malformation of the Parotid Gland Associated with Cowden Disease

Ⅰ．はじめに

　動静脈奇形（arteriovenous malformation：AVM）は，動脈と静脈間に毛細血管を介さない短絡を来す疾患であり，外傷性を除いては胎生早期に発生する先天性異常と考えられている．AVMは通常は頭蓋内に発生することが多く，頭蓋外に発生することは稀で，特に耳下腺に発生するAVMについての報告は非常に少ない．今回われわれは，癌抑制遺伝子であるphosphatase and tensin homolog deleted on chromosome 10（PTEN）遺伝子異常症候群の1つであるCowden病に合併し，耳下腺深葉部に生じた巨大AVMに対して術前塞栓術および摘出術を行い，良好な結果を得た1例を経験したので，文献的考察を加えて報告する．

　We report a rare case of arteriovenous malformation（AVM）of the parotid gland associated with Cowden disease successfully treated with preoperative embolization followed by surgical removal. A 39-year-old man with a history of Cowden disease presented with a pulsating and growing mass on his left lower jaw. Contrast-enhanced computed tomography（CT）and angiography revealed a high-flow AVM in the deep lobe of the left parotid gland.

　After intravascular embolization of the feeding arteries, surgery was performed using the NIM-response^®3.0, facial nerve monitoring system. The AVM was almost completely removed and the facial nerves were morphologically preserved. Interestingly, the intraoperative findings revealed that the enlarged vasa nervorum of the facial nerve also fed the AVM. Although left facial nerve palsy appeared after the surgery, the nerve function gradually improved over one year. No recurrence of the AVM has been observed for one year.