下垂体機能低下症を伴う内頸動脈大型動脈瘤に対し瘤内塞栓術を行った1例

Endosaccular Embolization of an Intrasellar Aneurysm with Hypopituitarism: Case Report

Ⅰ．はじめに

　一般に頭蓋内動脈瘤が原因で下垂体機能低下症を呈することは稀であるが²⁾，今回われわれは，下垂体機能低下症にて明らかとなった内頸動脈海綿静脈洞部の未破裂大型動脈瘤に対し瘤内塞栓術を行い，下垂体機能改善が得られた1例を経験したので報告する．

　An 81-year-old male presented with weight loss and hyponatremia. A baseline endocrinological examination revealed anterior pituitary dysfunction. A computed tomography and MRI revealed a large, unruptured intrasellar aneurysm protruding from the right internal carotid artery and pushing the pituitary stalk leftward. The patient developed polyuria and polydipsia from 10 days after commencing corticosteroid supplementation and was diagnosed with partial central diabetes insipidus (DI). Balloon assisted endosaccular embolization was performed about one month after the posterior pituitary dysfunction was identified. The unruptured aneurysm was successfully embolized with Guglielmi detachable coils (GDCs) without narrowing of the parent vessel. DI resolved completely and the posterior pituitary dysfunction imploved soon after endosaccular embolization. The remission of DI after coil embolization suggested that the DI might have been induced by the progressive mass effect of the aneurysm rather than by the steroid. An endocrinological evaluation and cerebral angiography confirmed partial recovery of anterior pituitary dysfunction and almost complete obliteration of the aneurysm, respectively, at 1 year after the operation. We report a case of hypopituitarism secondary to the large intrasellar aneurysm. This aneurysm was embolized with GDCs, resulting in partial recovery of anterior pituitary dysfunction and complete recovery of posterior pituitary dysfunction.