鼻腔腫瘤を伴った巨大な角膜デルモイドの1例

A case of enormous epibulbar dermoid associated with nostril dermoid tumor

　右眼球上腫瘤と左鼻腔腫瘤を認めた生後2日目の男児の1例を経験した．右眼球表面は全体に皮膚様組織で被われており角膜，結膜強膜は認められず，角膜に相当する部より鶉卵大の皮膚で被われた，弾性軟の球状腫瘤が瞼裂より前方へきのこ状に突出しており，中間透光体，眼底の透見は不可能であった．左眼には異常なかった．CT検査では右眼球は左眼球とほぼ同じ大きさに造影されたが，角膜上に半球状の腫瘤が認められ，虹彩，水晶体は不明瞭であった．左眼球のCT像は正常であった．

　家族が早期の形成手術を希望したので，生後12日目にて右眼球上腫瘤と左鼻腔腫瘤を摘出した．13mm×10mm×10mmで，病理組織学的診断はデルモイドで，皮下に脂肪と結合組織の増殖が認められた．

　染色体検査は正常で，家族歴に特記すべきことはなく，真の誘因は不明であるが，臨床的に，右眼の腫瘍は角膜ほぼ全体にみられ，虹彩，水晶体は未発達だが，眼球後部は正常であり，小眼球症も認められなかったことから，胎生期の異常は水晶体形成中（胎生5〜7週頃）に生じたと推定される．術後8カ月経過した現在，両腫瘤に再発はなく，さらに経過観察中である．

A 2-day-old male infant presented with an enor-mous epibulbar dermoid in the right eye, associated with dermoid tumor in the left nostril. The right eye was completely covered with skin tissue, and a robin-egg sized, elastic soft tumor with a stalk rising from the center of this skin tissue was seen through the lid fissure. The left eye showed normal appearance. CT examination showed a remarkable epibulbar tumor and unremarkable images of the iris and lens in the right eye. No abnormal findings were detected in the vitreous cavity or the posterior half of the eyeball. No abnormalities were found inthe left eye in the CT examination. Histopathological examination revealed the epibulbar growth to be a dermoid, composed of fibrous tissue and fatty tissue covered by normal stratified epidermis. The growth in the left nostril also proved to be a dermoid, composed of hyper-plasia of sebaceous gland.

Chromosome examination showed no abnormal-ities. The history of the child's parents was nega-tive. The definite cause for this particular abnor-mality remains unknown, but it is supposed that some insult might have occurred during 5 to 7 weeks of fetal age, based upon the clinical and CT findings in the affected eye. Eight months have passed without recurrence, since both tumors were excised.

Rinsho Ganka (Jpn J Clin Ophthalmol) 42(4) : 429-432, 1988