増殖前糖尿病網膜症における無灌流域面積の変化

Changes of retinal nonperfused area in preproliferative diabetic retinopathy

要約　目的：増殖前糖尿病網膜症での網膜無灌流領域の拡大に関与する因子の検討。対象と方法：光凝固を行っていない増殖前糖尿病網膜症10例10眼を対象とした。年齢は36～73歳（平均54歳），糖尿病の罹病期間は3～20年（平均12年）であった。12～20か月（平均16か月）の経過を観察した。画角50°の眼底カメラでフルオレセイン蛍光眼底造影を3回以上行い，無灌流領域の面積を画像解析で算出し，乳頭の面積に換算した。結果：無灌流領域の面積は有意に増加した（p＜0.05）。観察期間中のHbA_1cの増加率と無灌流領域の拡大率の間には正の相関があった。背景因子として，観察開始時の無灌流領域の面積とHbA_1cが，無灌流領域の拡大率と有意に相関していた。結論：増殖前糖尿病網膜症での網膜無灌流領域は増大する傾向があり，網膜無灌流領域が大きく，HbA_1cが高いほど拡大しやすい。

Abstract.　Purpose：To identify factors involved in enlargement of retinal nonperfused area in preproliferative diabetic retinopathy. Cases and Method：This retrospective study was made on 10 eyes of 10 cases of preproliferative diabetic retinopathy that had not received photocoagulation. Their age ranged from 36 to 73 years,average 54 years. Diabetes mellitus had been diagnosed 3 to 20 years,average 12 years,before. They were followed up for 12 to 20 months,average 16 months. The fundus was documented by fluorescein angiography at an angle of 50 degrees. The angiograms were used to quantitate area of retinal nonperfusion. Results：The area of nonperfusion increased during the follow-up（p＜0.05）. Rate of enlargement of nonperfusion showed positive correlation with increase in HbA_1c,initial value of HbA_1c,and initial area of nonperfusion. Conclusion：Area of retinal nonperfusion has a tendency to increase. Rate of increase is greater in cases with more extensive nonperfusion and with higher value of HbA_1c.