進行性の周辺虹彩萎縮を合併した発達緑内障の1例

Progressive atrophy of peripheral iris in a case of developmental glaucoma

要約　目的：進行性の周辺部虹彩萎縮を示した発達緑内障の症例の報告。症例：15歳男児が眼圧上昇で紹介受診した。8年前に左右眼の角膜径が13mmで，早発型発達緑内障が疑われたが，無治療であった。所見：矯正視力は右0.9，左1.0で，眼圧は右39mmHg，左19mmHgであった。右眼は−9D，左眼は−4Dの近視であった。角膜径が左右眼とも13mmで，虹彩周辺部に萎縮があり，全周に虹彩高位付着があったが，隅角が広く開大していた。乳頭の陥凹/乳頭径比は右0.8，左0.4であった。点眼で眼圧が下降せず，右眼に線維柱帯切除術を行った。10か月後の現在まで，眼圧の経過は良好である。結論：周辺虹彩萎縮の原因は不明であるが，眼圧コントロールが不良になり，緑内障が進行したことと関係する特殊な病態のあることが推定される。

Abstract.　Purpose：To report a case of developmental glaucoma who manifested peculiar atrophy of the peripheral iris. Case：A 15-year-old boy was referred to us for elevated intraocular pressure（IOP）. He had been seen by us 8 years before. He had shown corneal diameter of 13 mm in either eye leading to the tentative diagnosis of developmental glaucoma. He had been left untreated. Findings：Corrected visual acuity was 0.9 right and 1.0 left. IOP was 39 mmHg right and 19 mmHg left. Myopia of −9D and −4D was present in the right and left eye respectively. Corneal diameter was 13 mm in either eye. Both eyes showed atrophy of the peripheral iris with high insertion. Ultrasound biomicroscopy showed deep anterior chamber and wide open angle in both eyes. Cup-to-disc ratio was 0.8 in the right eye and 0.4 in the left. IOP failed to decrease by topical medication, necessitating surgical intervention by trabeculectomy. He has been doing well for 10 months until present. Conclusion：Atrophy of peripheral iris may have been etiologically related to elevated IOP and progression of glaucoma. There is a possibility that the present case shows a peculiar type of developmental glaucoma.