光凝所致糖尿病视网膜病变视网膜功能 改变的定量研究

目的探讨视网膜光凝术对糖尿病视网膜病变视网膜功能的早期影响。方法应用多焦视觉诱发反应图象系统(visual evoked response image system, VERIS )对21例30只眼Ⅲ～Ⅳ期糖尿病视网膜病变视网膜光凝术前、术后第3 d和术后第7 d的多焦视网膜电图(multifocal electroretinograms, MERG)进行了定量研究。结果与术前比较，光凝术后第3　d黄斑中央5°区域和鼻上象限N1波潜伏期显著延长，MERG各波反应密度均较术前显著降低。与接受光凝部位相应的视野鼻下象限N1波和P1波反应密度变化值大于其余三个象限，但仅在鼻下象限与颞上象限之间差异有显著性的意义。黄斑中央5°区域M ERG各波反应密度下降幅度最大，黄斑中央10°区域次之，均大于各象限。术后第3　d术眼视力的变化值与黄斑区各波反应密度的变化值呈显著的正相关。术后第7 d，MERG各波反应密度有所恢复，但N1波和P1波反应密度仍较术前降低。结论糖尿病视网膜病变视网膜光凝术后早期视网膜功能显著下降，光凝间接引起的黄斑区视网膜功能损害是术后早期部分患者中心视力下降的重要因素。(中华眼底病杂志,2001,17:181-183)

Quantitative investigation of early influences of laser photocoagulation on retinal function in diabetic retinopathy

ObjectiveTo investigate the early influences of laser photocoagulation on retinal function in diabetic retinopathy(DR)．MethodsThe multifocal electroretinograms (MERG) of 30 eyes with DR (phase Ⅲ～Ⅳ) were tested with visual evoked response image system IV b efore,and the 3^rd day and the 7^th day after laser photocoagulation． ResultsThree days after photocoagulation, the latency of N1 prolonged in the central macula 5° area and superionasal quadrant．Th e response densities of N1,P1 and N2 markedly reduced, and most significant changes occurred in the central macula 5° area and then in the central 10°area． There were also differences in the changes of the amplitude of N1 and P1 in diff erent quadrants ．The changes of visual acuity were positively related to the de crease of amplitudes of N1,P1 and N2 in the macula．ConclusionThe reduction of response densities in MERG reveals functional damage in diabetic retina occurring early after photocoagulation．The functional damage in macula induced indirectly by photocoagulation may explain the reduction of visual acuity after panretinal photocoagulation in some degree．(Chin J Ocul Fundus Dis, 2001,17:181-183)