视网膜电图震荡电位的研究进展及其在糖尿病视网膜病变中的应用

视网膜电图震荡电位（OPs）是叠加在视网膜电图b波上升段的数个高频率、有节律的小波。用现行国际临床视觉电生理学会视网膜电图记录标准所得到的OPs是来自视杆、视锥细胞的混合反应。近年来,对OPs的分离、纯化和定量技术取得较大进展。研究发现,视杆和视锥细胞引发的OPs有不同的特性。OPs可客观反映内层视网膜的功能,在糖尿病患者视网膜出现明显血管病变前,OPs即可出现振幅下降。随着对OPs具体成分的深入认识和分离技术的不断提高,纯净和无混杂成分的OPs在糖尿病视网膜病变病理损害发生机制的研究以及早期诊断和疗效随访中可能会发挥重要作用     

糖尿病视网膜病变患者的多焦视网膜电图研究进展

糖尿病视网膜病变(diabetic retinopathy,DR)是糖尿病患者主要的眼部并发症,可以导致视力的严重损害.多焦视网膜电图是一项新的视觉电生理测量方法 ,能在相对较短的时间内测量整个测视野中许多细小部位的视网膜电图,可以反映局部视网膜的功能,对于DR的早期诊断具有极其重要的价值,并且能够定量地监测DR的进展情况,判断疗效和预后.     

糖尿病视网膜1期病变多焦视网膜图变化分析

目的 通过检测糖尿病视网膜1期病变患者多焦视网膜电图(multifocal electroretino-gram,mfERG),评价1期糖尿病视网膜病变患者早期视功能的变化.方法 检测正常对照组31只眼,1期糖尿病视网膜病变组46只眼的mtERG在视野30°的测试范围内6个不同离心度的环形区N1、P1波潜伏期、P1波反应密度改变.结果 在视野30°的测试范围内6个不同离心度的环形区,1期糖尿病视网膜病变组(DR组)与正常对照组之间比较N1、P1波潜伏期显著延长;环1、2区DR组与正常对照组之间比较P1波反应密度显著降低.结论 尚未出现肉眼可见眼底改变的1期糖尿病视网膜病变即可出现视功能的异常,mfERG能够定量的检测1期糖尿病视网膜病变的局部视功能变化,为糖尿病视网膜病变的早期诊断提供有效方法.     

振荡电位和图形视网膜电图在亚临床期糖尿病视网膜病变诊断中的应用价值

目的探讨视网膜电图振荡电位(OPs)和图形视网膜电图(P-ERG)在亚临床期糖尿病视网膜病变中的变化特点,并比较振荡电位和图形视网膜电图检测糖尿病患者视网膜功能异常的敏感性。方法选择确诊为Ⅱ型糖尿病,经检眼镜检查、眼底摄片检查,眼底无糖尿病视网膜病变的60例(120只眼)患者,进行振荡电位 (OPs)和图形视网膜电图(P-ERG)检查,观察亚临床期糖尿病视网膜病变的OPs总波幅及各子波波幅、潜伏期和 P-ERG的b波波幅、潜伏期的变化,并与正常组对照。结果在亚临床期糖尿病视网膜病变时,OPs总波幅及各子波波幅和P-ERG的b波波幅均降低,与正常对照组比较,差异均有显著性;但潜伏期在两组间无明显差异。亚临床期糖尿病视网膜病变组OPs总波幅和P-ERG的b波波幅的异常率分别为51．67％和36．67％,两者间差异有显著性。结论 OPs总波幅及各子波波幅和P-ERG的b波波幅在亚临床期糖尿病视网膜病变时即有改变,波幅的改变比潜伏期改变敏感;OPs检测方法较P-ERG敏感,提示OPs能更早、更准确地反映视网膜微循环机能的变化。因此OPs可作为诊断早期糖尿病视网膜病变较敏感的指标。     

早期糖尿病视网膜病变的视网膜电图分析

目的 分析早期糖尿病视网膜病变(DR)的闪光视网膜电图(F—ERG)和视网膜电图震荡电位(OPs)各参数的变化特点，寻找反映早期DR的敏感指标。方法 对16例(32只眼)正常人进行OPs和F-ERG检测。对27例(53只眼)糖尿病病人进行眼底荧光血管造影(FFA)、OPs和F—ERG检测。结果 OPs中Os波幅、O4波幅、OPs总波幅及F-ERG中b波峰潜时较其他指标敏感，其中O4波幅和b波峰潜时为最敏感指标，但均不能反映早期DR的严重程度。结论 OPs的O4波幅和F—ERG的b波峰潜时可作为早期糖尿病视网膜病变诊断的敏感指标。     

三个时期糖尿病视网膜病变多焦视网膜电图的差异

目的研究三个时期糖尿病视网膜病变的多焦视网膜电图特征及其临床意义。方法采用VERISⅣ视觉诱发反应图像系统测量和分析了34例非增殖期、15例增殖前期和15例增殖期糖尿病视网膜病变的多焦视网膜电图的差异。结果与正常对照眼比较,增殖期糖尿病视网膜病变,多焦视网膜电图的N     

微视野计在糖尿病视网膜病变的临床应用

糖尿病视网膜病变严重影响视功能，其诊断、随访需要适当的视功能检查，糖尿病黄斑水肿治疗的安全性需要精确地评估。视网膜成像技术的进步使当前眼科诊断产生巨大革新，使医师可以发现早期视网膜改变，并记录治疗效果。然而，将视功能的主观改变与临床变化相联系仍充满挑战。微视野计使获得眼底相关量化的视网膜敏感度成为可能，正在改变着当前对糖尿病视网膜病变视功能的研究。本文对微视野计在糖尿病视网膜病变视功能评估、早期诊断、治疗评价方面的应用进行综述。     

糖尿病视网膜病变的多焦视网膜电图的研究进展

糖尿病视网膜病变(DR)是糖尿病并发的一种严重的致盲性眼病,其复杂的病理变化破坏了视网膜的正常功能.多焦视网膜电图(mERG)作为一项新的视觉电生理检查技术,能在相对较短的时间内测量整个测视野中许多细小部位的ERG,其一阶反应可反映局部视网膜内层和外层的功能,目前这项技术在糖尿病视网膜病变的研究中得到了广泛的应用.本文就近年来糖尿病视网膜病变的多焦视网膜电图的研究进展做一综述.     

视网膜电图在研究高海拔视网膜病变中的应用

随着高原经济的发展和高原人群活动的日渐频繁,高原相关疾病成为了社会和医学的关注焦点,亦成为了制约高原发展的重要因素.高海拔视网膜病变(high altitude retinopathy,HAR)作为高原相关疾病的一种,主要表现为视网膜血管的充血、迂曲,以及视网膜出血、玻璃体腔出血.HAR早期效应可表现为短暂的视功能障碍,长期效应则为视力不可逆损伤和眼部并发症.HAR重在预防,早期诊断并及时治疗,预后较好.视觉电生理学检查技术以其独特的优势在眼科疾病的诊断鉴别、预后判定、疗效评价等方面具有重要作用.视网膜电图(electroretinogram,ERG)是视觉电生理检查中的重要组成部分,作为视网膜功能的一种客观的检查方法,应用于高海拔视网膜病变的检查中,不仅可以评估在高海拔下视网膜的功能的变化,早期发现还未出现临床表现的HAR,还可动态观察HAR的发展及治疗效果.     

糖尿病视网膜病变黄斑区的光学相干断层扫描及多焦视网膜电图图像特征

为了解糖尿病视网膜病变黄斑区的组织结构的改变及其相应的视网膜功能变化的关系。我们应用了光学相干断层扫描（ｏｐｔｉｃａｌ ｃｏｈｅｒｅｎｃｅ ｔｏｍｏｇｒａｐｈｙ,ＯＣＴ）及多焦视网膜电图（ｍｕｌｔｉｆｏｃａｌ ｅｌｅｃｔｒｏｒｅｔｉｎｏｇｒａｐｈｙ,ｍ－ＥＲＧ）检测了Ⅲ～Ⅳ期糖尿病视风膜病变患者３８例６０眼,结果显示ＯＣＴ图像特征大致可分五种形态,ｍ－ＥＲＧ反应密度图形可以反映出黄斑的视网膜功能并与黄斑区的组织形态的改变有较密切的关系。ＯＣＴ及ｍ－ＥＲＧ的应用为糖尿病视网膜病变患者黄斑病变的组织形态和视网膜功能的评价及随访提供可靠的检测手段。     

Early diagnosis of retinal changes in diabetes: a comparison between electroretinography and retinal biomicroscopy

The present study was undertaken in order to find out whether electroretinographic examinations could reveal signs of functional abnormalities before morphological changes are detected in the diabetic retina. Pattern-reversal and flash electroretinograms (ERG) and oscillatory potentials (OP) were recorded in 24 diabetics and 10 age-matched normal controls. The diabetic group consisted of 11 patients without retinopathy and 13 patients with background retinopathy. No significant changes in pattern-reversal or flash ERG or OP amplitudes were observed in the diabetic group with normal fundus or with background retinopathy. The findings imply that ERG examination with the described techniques does not reveal retinal dysfunction in diabetics before retinopathy can be detected by means of retinal biomicroscopy.     

The electroretinogram in diabetic retinopathy.

Electroretinography (ERG) is an objective method of evaluating retinal function. Since its introduction to clinical practice in the 1940s, it has become a useful and routine diagnostic clinical tool in ophthalmology. This review summarizes the role of ERG as a clinical technique for evaluating the progression of diabetic retinopathy and as a research tool for increasing our understanding of the pathophysiology of diabetic retinopathy. Most studies show unequivocally that the different types of ERG tests detect local abnormalities or widespread pathology, even in very early stages of the disease. It seems plausible that measurements from ERG recordings, particularly the oscillatory potentials, may be useful for predicting progression from nonproliferative to the more sight-threatening stages--preproliferative or proliferative--of diabetic retinopathy. Some recent work implies that the ERG can also be a useful diagnostic method for discriminating between eyes with diabetic retinopathy and those without the condition.     

A comparison of photopic and scotopic electroretinographic changes in early diabetic retinopathy.

Previous studies of early diabetic retinopathy have shown that oscillatory potential (OP) amplitudes are reduced in many diabetic patients. OP amplitude is believed to be a more sensitive indicator of the development of future retinopathy than b-wave amplitude of the scotopic electroretinogram (ERG). Because OPs measured to a bright white flash reflect both rod and cone system activity, it is important to compare OP amplitudes to photopic ERG measures as well as scotopic measures in early diabetic retinopathy. In this study, OPs and ERG responses were measured under photopic and scotopic conditions in a group of diabetic patients. Although OPs were reduced in amplitude in the diabetic group, several other parameters of the scotopic and photopic b-waves were impaired. The results indicate that b-wave activity may indicate retinal changes in early diabetic retinopathy in the same manner as the OPs.     

Therapeutic targeting of diabetic retinal neuropathy as a strategy in preventing diabetic retinopathy

Diabetes causes a panretinal neurodegeneration herein termed diabetic retinal neuropathy, which manifests in the retina early and progresses throughout the disease. Clinical manifestations include changes in the ERG, perimetry, dark adaptation, contrast sensitivity and colour vision which correlate with laboratory findings of thinning of the retinal neuronal layers, increased apoptosis in neurons and activation of glial cells. Possible mechanisms include oxidative stress, neuronal AGE accumulation, altered balance of neurotrophic factors and loss of mitohormesis. Retinal neural damage precedes and is a biologically plausible cause of retinal vasculopathy later in diabetes, and this review suggests that strategies to target it directly could prevent diabetes induced blindness. The efficacy of fenofibrate in reducing retinopathy progression provides a possible proof of concept for this approach. Strategies which may target diabetic retinal neuropathy include reducing retinal metabolic demand, improving mitochondrial function with AMPK and Sirt1 activators or providing neurotrophic support with neurotrophic supplementation.     

Multifocal electroretinogram in diabetic subjects

PurposeTo identify local retinal abnormalities and evaluate the nature and extent of retinal dysfunction in diabetics using full field electroretinogram (ERG) and multifocal ERG (MF-ERG) and to determine the correlation between features of optical coherence tomography (OCT) and MF-ERG.MethodsTwenty-eight normal subjects (Control Group; 56 eyes) and 37 patients (72 eyes) with diabetes mellitus (DM Group) were evaluated. In the DM Group, 17 eyes had no retinopathy (grade 1), 18 eyes had early non proliferative diabetic retinopathy (NPDR) (grade 3), 16 eyes had late NPDR (grade 4), 21 eyes had proliferative diabetic retinopathy (PDR) (grade 5). Full field ERG and MF-ERG, were used to assess the effects of diabetic retinopathy on retinal function. OCT and fluorescein angiography were used to assess and compare morphological changes with functional changes in diabetes mellitus.ResultsIn diabetic patients without retinopathy (17 eyes), the amplitudes of the second order component of MF-ERG were reduced and implicit times were delayed, while only implicit times of first order component of MF-ERG were delayed but the amplitudes of first order component were normal. In diabetic patients with retinopathy (55 eyes), the overall amplitudes were reduced and peak implicit time increased in the first order component and second order component.OCT of the DM Group showed the fovea of eyes with edema were thicker than the Normal Group. The fovea of eyes with cystoid macular edema (CME) were significantly thicker than the fovea of eyes with diffuse swelling. The implicit times of MF-ERG were directly correlated with foveal thickness.ConclusionMF-ERG reveals local retinal dysfunction in diabetic patients. MF-ERG offers the advantage of topographic mapping of retinal dysfunction. The magnitude of delay of MF-ERG implicit time reflects the degree of local clinical abnormalities in eyes with retinopathy. Local response delays found in eyes without retinopathy detects subclinical local retinal dysfunction in diabetics. The combination of OCT and MF-ERG may provide objective criteria for evaluation and assessment of diabetic retinopathy.     

视网膜电图PhNR和OPs在非增生型DR中的变化特点

目的观察非增生型糖尿病视网膜病变（DR）中视网膜电图PhNR和OPs的变化特点,比较OPs、PhNR指标在早期诊断及评估视网膜功能的敏感性和特异性。方法选取经间接检眼镜、荧光素眼底血管造影（FFA）确诊的DR患者30例（30眼）,同时选取与其性别、年龄相匹配的正常对照25例（25眼）作为对照组。2组均进行视力、闪光视网膜电图（F-ERG）、FFA检查。比较2组PhNR振幅、OPs振幅及ERG其他参数指标,并探讨不同DR分级与PhNR振幅、OPs振幅的变化关系。结果在OPs指标中,DRⅠ~Ⅳ级OPs振幅与正常值比较差异均有统计学意义（P〈0.05）,PhNR指标显示,DRⅠ级PhNR振幅与正常值比较,差异无统计学意义（P〉0.05）,DRⅡ~Ⅳ级与正常组比较,差异均有统计学意义（P〈0.05）。在比较各参数ROC下面积（AUC）中,OPs指标的AUC最高,为0.866;其次是PhNR指标,AUC为0.754。OPs诊断NPDR的敏感性和特异性分别为63.6%和80%,而PhNR的敏感性和特异性分别为54.5%和73.3%。结论DR在病变初期即出现血液循环性改变、神经细胞功能障碍,表现为PhNR振幅和OPs振幅均明显降低。OPs指标在DR的早期诊断及评估视网膜功能方面敏感性和特异性更高。     

Oscillatory potentials of local macular ERG in diabetic retinopathy

The oscillatory potentials (OPs) in electroretinogram (ERG) have clinical values in measuring retinal functions of the early stage of diabetic retinopathy. However, OPs have, until now, been evaluated as components of total ERG recorded with a full field stimulus over the entire retina. Therefore, little information could be obtained about the macular condition (diabetic retinopathy). Using focal stimuli, we successfully recorded OPs in the human macular region. We modified our previously reported system for recording local macular ERG under the fundus monitor with an infrared television fundus camera. We evaluated macular OPs with simultaneously recorded a- and b-waves in many patients with diabetic retinopathy. In some kinds of early diabetic maculopathy, the macular OPs were selectively reduced, leaving the a- and b-waves intact. The macular OPs can be a valuable indicator in assessing the macular function in diabetic maculopathy.