糖尿病網膜症の動静脈短絡路

Arteriovenous shunts in diabetic retinopathy

　われわれは，単純性から増殖性を含む糖尿病網膜症716眼の螢光眼底造影所見を解析し97眼13.5％に動静脈短絡路が存在することを明らかとした。そのうち，連続撮影で確認できなかったが，動脈と静脈が形態的に連絡している短絡路は56眼あり，連続撮影で証明された機能的にも真の短絡路は41眼あった。後者は，以下の3型に分類された。①細動静脈経由のもの，②拡張した毛細血管経由のもの，③異常血管経由の短絡路である。動静脈短絡路の出現頻度は，糖尿病網膜症の進行度と関係があり，病期が進行するほどその発生頻度も増加し，増殖網膜症では21％に達することが明らかとなった。糖尿病網膜症に動静脈短絡路が存在するという事実は，今まで明らかにされている糖尿病網膜症の進行因子を，再検討する余地のあることを示していると考える。

We reviewed fluorescein angiograms in 716 eyes with simple or proliferative diabetic retinopathy with paticular attention to identify arteriovenous shunts in the retina, There were 56 eyes with morphological arteriovenous communications. Additionally, there were 41 eyes with functional arteriovenous shunt formations. These vessels were characterized by rapid and preferential dye transit from an arteriole to a venule. They were formed either through direct communication of an arteriole with a venule, through dilation of capillary chan-nels, or through formation of an abnormal, occa-sionally newly formed shunting vessel. The inci-dence of arteriovenous shunt increased along with the progression of retinopathy. Arteriovenous shunt was present in 21 % of eyes with proliferative diabetic retinopathy. It is claimed that arter-iovenous shunt formation represents one of the frequent and basic patterns of retinal vascular disorder in diabetic retinopathy. It also appeared that formation of arteriovenous shunt would accel-erate retinal capillary nonperfusion in the adjacent or peripheral retina.