ひょうたん型眼球を呈した1例—異常収縮運動のみられた乳頭周囲ぶどう腫

Contractile peripapillary staphyloma in a case of hourglass-shaped eyeball

　内斜視を主訴として受診した3歳11カ月，女子の乳頭周囲ぶどう腫にみられた狭窄部での異常収縮運動を螢光眼底撮影で記録観察し，またCT scanで小眼球を示す前半分とぶどう腫にあたる後半分とがほぼ同じ大きさのためひょうたん形を示した．内斜視の矯正手術を行ったところ小眼球とぶどう腫の境界部に付着したretractor bulbi muscleを思わせる光沢のある強靱な筋性膜様組織が眼球後部へと伸展していた．この膜様組織を切除しぶどう膜の色調がみられる強膜ぶどう腫が観察された．乳頭周囲ぶどう腫における収縮運動の原因としてretractor muscleと思われる組織を観察した報告は文献上みられないので考察を加えて報告した．

We observed an unusual anomaly of the fundus in the left eye of a girl aged 3 years 11 months. There was a well-formed peripapillary staphyloma which was as large as the eyeball itself, resulting in an hourglass-shaped eye. A rhythmical spontane-ous contracture was observed along the most con-stricted portion of the eye both by ophthamoscopy and by fluorescein angiography. Observation during surgery for correction of esotropia confirmed the presence of firm muscular membrane adhering to the site of constriction and extending posteriorly.The observed spontaneous contraction of the en-trance of staphyloma was thus attributed to the presence of retractor muscle-like structure.