海綿静脈洞部に進展した傍鞍部脊索腫の1例

A case of parasellar chordoma invading the cavernous sinus

　片側外転神経麻痺で発症し，約2年の後に全眼筋麻痺に進展し，診断のついた傍鞍部脊索腫の73歳男性を経験した。

　片側性の外転神経麻痺などの外眼筋麻痺をみた場合，少なからず頭蓋内腫瘍によるものがあり，頭蓋底部の腫瘍の可能性を念頭に置き，造影剤の使用を含めたCT scanや，MRIなどの精査を積極的に行うべきと思われた。

A 73-year-old male presented with diplopia since 6 months before. He was diagnosed as right ab-ducens palsy on neurological examinations. Plain x -ray and computed tomography (CT) gave equivo-cal results. During the following 2 years, the condi-tion progressed into right total ophthalmoplegia. CT scan showed a space-occupying lesion erodingthe lateral portion of the sella turcica. Magnetic resonance imaging (MRI) showed a right parasel-lar mass involving the cavernous sinus and extend-ing into the retropharyngeal space. Surgery by right frontotemporal craniotomy gave the his-tological diagnosis of chordoma. This case illus-trates the necessity of close follow-up by repeated CT and MRI examinations in the presence of unilat-eral, slowly progressive paresis of external ocular muscles.