下垂体卒中様発作にて発症した内頸動脈瘤破裂の1例

A Case of Ruptured Internal Carotid Artery Aneurysm Mimicking Pituitary Apoplexy

Ⅰ．はじめに

　下垂体卒中とは下垂体腫瘍内の出血・梗塞により起こる症候群のことであり，それほど稀な病態ではない¹⁾．また下垂体腫瘍を有する患者では脳動脈瘤が存在する率が健常人よりも高いという報告や^10,11)，同等であるという報告がある⁶⁾．しかし，下垂体卒中に未破裂脳動脈瘤が合併したり⁴⁾，脳動脈瘤破裂に下垂体腫瘍^6,11)が合併するのは稀である．さらに内頸動脈瘤が下垂体腫瘍内部に出血した症例は極めて稀である⁹⁾．今回，内頸動脈海綿静脈洞部の脳動脈瘤が下垂体腫瘍内に破裂し，下垂体卒中様発作で発症した症例を経験した．

　脳動脈瘤に対してはコイル塞栓術を，下垂体腫瘍に対しては薬物治療を選択して良好な結果を得たので文献的考察を加えて報告する．

　A 48-year-old female presented with a sudden onset of headache and visual impairment. Nineteen years before, she had undergone a transsphenoidal surgery for a prolactin producing pituitary adenoma at our hospital without intraoperative arterial bleeding. On arrival, she exhibited dilated pupils and loss of bilateral visual acuity, but improved immediately after all examinations. MRI revealed a pituitary tumor with intratumoral hemorrhage, intraventricular hemorrhage and subdural hemorrhage. Cerebral angiography revealed a left intracavernous carotid artery aneurysm. Her medical history and radiological findings suggested the rupture of a de novo aneurysm causing a hemorrhage into a pituitary adenoma mimicking pituitary apoplexy. Endovascular occlusion of the aneurysm was performed by use of platinum coils. Because of rapid improvement of visual acuity, administration of terguride was chosen for shrinking the pituitary adenoma. If a pituitary adenoma is present, the possibility of a coincidental aneurysm should always be considered. This association should be kept in mind when evaluating any case of pituitary apoplexy.