高血圧による一過性の神経血管圧迫症候群をきたした遺残性三叉動脈と遺残性舌下動脈の併存例

A case of Coexistent Persistent Trigeminal and Hypoglossal Arteries Manifested with Neurovascular Compression Syndrome by Hypertension

急性発症の右眼窩部痛と複視で来院した70歳女性。高血圧を認め，神経学的に右眼球下転制限を認めた。CT angiographyとMRIにて内側型右遺残性三叉動脈，右遺残性舌下動脈，bovine型大動脈弓を認めた。眼球下転制限と右眼窩部痛の原因として右内頸動脈の内側型右遺残性三叉動脈分岐による海綿静脈洞内での外側偏奇による動眼神経・滑車神経，三叉神経第1枝の圧迫が疑われた。血圧の正常化ともに症状は改善した。発生学的原因として，右後交通動脈と両側椎骨動脈は無〜低形成であったことから，胎児期に後方循環系への十分な血流の供給路として複数の原始血管吻合が遺残し，一過性高血圧による神経血管圧迫症候群への関与が考えられた。

Abstract

A 70-year-old woman visited our hospital with hypertension, diplopia, and right orbital pain. Neurological examination revealed right ophthalmoplegia. CT angiography and MRI identified a right persistent trigeminal artery (PTA), right persistent hypoglossal artery, and bovine aortic arch. The right internal carotid artery (ICA) was displaced laterally in the cavernous sinus due to the bifurcation of the PTA. Compression of the right oculomotor nerve, right trochlear nerve, and first division of the right trigeminal nerve by the elongated right ICA was noted and considered a potential cause of the ophthalmoplegia and orbital pain. Symptoms improved with normalization of blood pressure. During embryonic development, the right posterior communicating artery and bilateral vertebral arteries were aplastic or hypoplastic, which suggests that these carotid-basilar anastomoses may have remained as supply routes to provide sufficient blood flow to the posterior cerebral circulation. This is an extremely rare case of embryological implications manifested with neurovascular compression syndrome.

(Received 6 January, 2022; Accepted 17 February, 2022; Published 1 June, 2022)