髄液鼻漏で発症した斜台部脊索腫の1例

A Case Report of Clivus Chordoma Presenting with Cerebrospinal Fluid Rhinorrhea

Ⅰ．はじめに

　髄液鼻漏は外傷性，非外傷性に大別され，前頭蓋底やトルコ鞍など鼻・副鼻腔に接する骨・硬膜といった構造物が破壊されて生じる．非外傷性では頭蓋底腫瘍による髄液漏の報告がなされているが，斜台部の骨欠損・骨破壊による髄液漏で発症する疾患として，脊索腫は稀な疾患である⁷⁾．今回われわれは，髄液鼻漏で発症し，長期経過後に脊索腫と診断された1例を経験したので，文献的な考察を交えて報告する．

　Chordomas are uncommon tumors occurring from remnants of the notochord. They are mainly localized in the sacrococcygium, the spine and the central skull base. Here we report a rare case of clivus chordoma presenting with cerebrospinal fluid（CSF）rhinorrhea. A 41-year-old man with a 11-year history of recurrent CSF rhinorrhea was found to have a clival lesion. Bone image CT revealed lytic bone destruction at the clivus. MRI showed a cystic mass with a membrane enhanced by gadolinium protruding into the sphenoid sinus thorough the bone defect. However, there was no solid component observed. The membrane was partially resected and the CSF fistula was repaired via endoscopic endonasal approach. The pathological diagnosis was chordoma, and there has been no recurrence for three years after the surgery. It is necessary for chordoma to be considered as a differential diagnosis for cystic lesions of the clivus when the cyst membrane is enhanced by gadolinium.