乳頭上新生血管を伴った非定型網膜色素変性症

Disc neovascularization developed in a case with atypical retinitis pigmentosa

　非定型網膜色素変性症の症例に乳頭上新生血管（NVD）の出現を認めた．症例は38歳，男性．左眼視力低下にて来院．既往歴，家族歴に特記事項なし．初診時視力は右0.8（1.0），左0.3（0.4）．両眼底にvascular arcadeに沿う灰白色の輪状病巣を認め，左眼にNVDと網膜前および硝子体出血を認めた．螢光眼底検査は病巣に一致した過螢光とNVDよりの色素漏出および類嚢胞黄斑浮腫像を示した．ERG・EOGはsubnor-mal．Goldmann視野計にて弓状暗点を認め，第2次暗順応が低下していた．左眼に汎網膜光凝固を施行しNVDの退縮をみた．初診の約3年後には右眼にもNVDを生じた．網膜色素変性症のNVD合併例は，現在まで2報告のみでその発生機序は不明である．網膜および網膜色素上皮の変性に起因する炎症の存在，網膜循環不全による酸素供給の低下，さらに非定型網膜色素変性症における酸素供給の必要な健常網膜の残存などがNVD発生に関与したものと考えた．

A 38-year-old male sought medical advice on account of blurred vision LE. Corrected visual acuity was 1.0 RE and 0.4 LE. Funduscopy showed grayish lesions along the vascular arcades arranged in an arcuate to ring-shaped pattern in both eyes. The left eye showed, additionally, disc neovascular-ization, preretinal and vitreous hemorrhages. The grayish lesions showed hyperfluoresence on fluores-cein angiography.

ERG and EOG were subnormal. Dark adaptation was impaired in the second phase. We diagnosedthe patient as atypical retinitis pigmentosa.Panretinal photocoagulation induced regression of disc neovascularization in the left eye. Similar disc neovascularization developed in the right eye 3 years later.

Only 2 cases are forthcoming in literature report-ing disc neovascularization in retinitis pigmentosa. As contributing factors for development of disc neovascularization, we presumed inflammation associated with degeneration of the retina and the pigment epithelium, decreased oxygen supply due to insufficient retinal circulation, and the presence of oxygen-demanding normal retinal areas in atypical retinitis pigmentosa.

Rinsho Ganka (Jpn J Clin Ophthalmol) 42(4) : 355-358, 1988