早期糖尿病性视网膜病变mf-ERG一阶kernel反应改变

Changes of the mf-ERG first order kernel in early diabetic retinopathy

目的 观察早期糖尿病性视网膜病变（简称糖网病）眼视网膜功能。方法将临床确诊为糖尿病并且最佳矫正视力在1．0以上、OCT检查视网膜厚度正常、眼底镜检正常或为轻度非增生性糖尿病性视网膜病变患者共27例54眼作为糖尿病组（按眼底检查情况分为轻度糖网病组与糖尿病无糖网病组）；另将正常同龄27例35眼作为正常对照组，分别行多焦视网膜电图一阶kernel反应（first order kernel）检查；将检查结果分别作比较。结果 与正常对照组相比，糖尿病组FOK P1波1环的振幅密度值降低，差异有高度显著性（P=0．0002）；N1波5环、P1波4～5环的峰时均有延迟，差异有显著性（P=0．0378、0．0172、0．0026）；其后极部30°范围内P1波峰时也延迟，差异有显著性（P=0．0121）。与糖尿病无糖网病组相比，轻度糖网病组FOK N1波4环的振幅密度值增高，差异有显著性（P=0．0469）；N1波3、5环，P1波3～5环的峰时均延迟，差异有显著性（P=0．0084、0．0428、0．0102、0．0128、0．0070）；其后极部30°范围P1波峰时明显延迟，差异有高度显著性（P=0．0027）。结论糖尿病患者视力尚正常时，其黄斑中心凹感光细胞功能已有所下降；早期糖网病FOK局部反应增高可能与糖尿病早期视网膜局部血流异常增加有关；糖尿病眼FOK的峰时延迟较振幅下降更为敏感，峰时可作为糖网病检测的独立指标；早期糖网病眼视网膜功能异常并非仅局限于内层视网膜；FOK是检测早期糖尿病性视网膜病变的有效手段。

Objective To observe the retinal function in the early diabetic retinopathy（DR）. Methods The first order kernel （FOK） of the multifocal electroretinogram（mf-ERG） was performed in 27 cases （54 eyes） with the diabetic mellitus（DM） group, which had the best corrected visual acuity of 1.0 or more, the normal retinal thickness manifested by the optical coherence tomography （OCT）, and the normal retina or mild non-proliferative diabetic retinopathies （NPDR） discriminated by the ophthalmoscope. FOK was also performed in 27 cases with the mine ages（ 35 eyes） who served as the normal subjects. FOK was compared tween the two groups. Results Compared with the normal subject, in DM, the FOK amplitude of the P1 ring1 was significantly decreased（P=0.000 2）. The latency of the N1 rings,P1 ring4-5 was statistically delayed（P=0.037 8,0.017 2 and 0.002 6）.The P1 latency of its 30° post-polar retina was also statistically delayed （P=0. 012 1 ）. Compared with the NDR, the NPDR N1 amplitude located in ring4 was statistically increased （P=0.046 9）. And the latency of the N1 ring3.5, P1 ring3.5 was all statistically delayed （ P=0.008 4,0.042 8,0.010 2,0.012 8 and 0.007 0）.The P1 latency of its 30° post-polar retina were significantly delayed（P=0. 002 7）. Conclusion The function of the photoreceptor cells in the macular fovea has declined even when the diabetic patients＇ visual acuity is still normal. The increased focal FOK response in early DR may be related to the increasing local blood fluid of the early DM. In DM, the delayed latency seems more sensitive than the decreased amplitude, and the area influenced is even larger. Latency may be an independent item served in the DR detection. The abnormality of the retinal function may not only locatein the inner retina in early DR. FOK is a useful tool in early DR detection.