多焦视网膜电图的临床应用进展

多焦电生理技术可在相对较短的时间内记录测试野内许多局部视网膜电图的反应波形,有助于了解视网膜或视路病变的机制,可用于一些眼病的早期诊断及预后,能客观和敏感地观察药物或手术的疗效。现将多焦视网膜电图在眼科临床中的研究进展作一综述。     

多焦视网膜电图技术及临床应用

多焦视网膜电图是视觉电生理学的一项重要新进展,它应用先进的数字信号处理和电子计算机技术,可在较短时间内同时测量几十度视野范围内几十到几百个区域的局部视网膜电图,并计算各局部反应的一阶反应和二阶反应,根据各反应的参数分 别了解视网膜内外层对应于视野各部位的功能,目前该技术已在临床上得到应用。（中华眼底病杂志,2000,16：1-70）     

多焦视网膜电图在视网膜疾病中的应用进展

多焦视网膜电图(mfERG)是视网膜电图(ERG)中的一种常见类型,它能够客观、准确、定量地检测视网膜各个细小部位的功能,在临床上被广泛应用,尤其是在视网膜疾病中,它不仅在视网膜疾病的诊断与疗效评价中有着重要作用,而且最近的研究发现它在疾病的随访和预后评估中也具有重要价值,甚至其应用范围可向基础研究推广。因此本文对mfERG在视网膜疾病中的应用进展作一综述。     

多焦视网膜电图的研究及临床应用

本文对多焦视网膜电图的产生及仪器,方法,记录条件和临床应用等方面进行了综述。该检查方法对于对后极部视网膜功能的测定较其它电生理方法更客观有效,尤其适用于黄斑病变等局部小病灶的诊断。     

Stargardt病的多焦视网膜电图

目的观察Stargardt病多焦视网膜电图(multi-focal electrore tinogram, mERG)变化特点。方法用VERIS 4.0视觉诱发反应成像系统 ,对7例Stargardt病患者的14只患眼进行mERG测定,并与正常对照者的mERG检查结果进行比较。结果接受检查的所有Stargardt病患眼的mERG均有显著异常,各部位mERG N₁、P₁波振幅明显降低 ,潜伏期明显延长(P<0.01);不同部位N₁、P₁振幅降低程度不一致,以中心凹振幅降低最为显著,平均振幅分别只相当于正常人的19%和10%,随着离心度的增大,振幅差异逐渐减小;患者mERG地形图可分为中心降低型和弥漫降低型2种形式。结论Stargardt病的mERG有明显异常改变,表现为黄斑中心凹功能损害最严重。(中华眼底病杂志,2001,17:271-273)     

多焦视网膜电图及其应用

传统的视觉电生理是临床和基础研究中常用的检查方法 ,发挥着非常重要的作用 ,目前仍是眼科的主要检测手段之一 ,但是也存在着一些局限性。一方面 ,由于某些视野的局部功能异常在全视野视网膜电图 (ｆｕｌｌｆｉｅｌｄｏｒＧａｎｚｆｅｌｄｅｌｅｃｔｒｏｒｅｔｉｎｏｇｒａｍ)     

多焦视网膜电图与多焦视诱发电位检测的原理和临床应用

一、多焦视网膜电图 (ｍｕｌｔｉ ｆｏｃａｌＥＲＧ ,ｍＥＲＧ)的产生1877年Ｄｅｗａｒ首先记录了人眼对视刺激的电反应。1941年 ,Ｒｉｇｇｅｓ把接触镜电极引入到记录视网膜电图中(ｅｌｅｃｔｒｏｒｅｔｉｎｏｇｒａｍ ,ＥＲＧ) ;Ｋａｒｐ应用这种方法首次记录了视网膜色素变性中独特的ＥＲＧ反应。Ｓｕｔｔｅｒ和Ｔｒａｎ[1] 在 1992年发明了一种多焦ＥＲＧ系统 ,同时刺激视网膜的多个部位 ,独立采集每一处的反应情况[2 ] ,用地形图的方式直观显示视网膜各部位的反应情况。ｍＥＲＧ同时记录大量局部视网膜的反应 ,可以在短时间内发现细微…     

多焦视网膜电图的重复性探讨

多焦视网膜电图 (multifocal electroretinogram,m ERG)的刺激阵列由随离心度增加而面积相应增加的六边形组成 ,并由m-序列调制 ,可以同时分别刺激视网膜的各个不同部位 ,并将反应分离提取出来 ,可分析不同象限、不同环的反应密度及潜伏期 ,进而了解视网膜不同部位的功能状况。由于它较传统视觉电生理检查有其独到之处 ,因而越来越多地被运用到眼底病的相关研究领域[1 - 3 ] 。但是 ,目前对该系统重复性的研究国内外报道不多 ,我们通过对 16名正常人 16只眼的前后 2次 m ERG检测 ,对其重复性进行了探讨 ,现将结果报道如下。1　对象和方法…     

视网膜脱离手术前后的多焦视网膜电图比较

目的探讨视网膜脱离手术前后多焦视网膜电图(multifocal electroretinography, mERG)的改变及其临床应用价值。　方法应用VERIS Science ^TM4.0对18例(18只眼)裂孔源性视网膜脱离患者手术前后分别进行mERG检查,并对不同区域的mERG进行了比较。结果手术前脱离区a、b波的潜伏期比非脱离区明显延长,差异有显著性的意义(t＝4.541、t＝6.784,P<0.01),脱离区a、b波的振幅密度明显小于非脱离区,差异有显著性的意义(t=3.680、t＝4.257,P<0.01);手术后中心凹、黄斑区、黄斑外区及全测试区的a、b 波的振幅密度均比手术前明显提高(P<0.01),但是a、b波的潜伏期手术前后则无明显变化(P>0.05);手术后原脱离区a、b波的振幅密度均比术前有明显提高(P<0.05)。　结论视网膜脱离复位术后视网膜功能有一定提高,mERG是评价术后视网膜功能恢复的有用工具,振幅密度比潜伏期更敏感。(中华眼底病杂志,2001,17:264-267)     

多焦视网膜电图评价视网膜脱离的视网膜功能

目的 探讨多焦视网膜电图(multifocal electroretinography, MERG)对视网膜脱离(retina detachment, RD)的视功能客观评价意义。 方法 应用VERIS 4.0视诱发反应图像系统检测21例RD患者的22只患眼和36例正常人的42只眼的MERG。测试野的水平视角为±26.6°,垂直视角为±22.1°,采用Burian-Allen接触镜电极,在8 min(分16段)记录103个视网膜部位的反应。 结果RD眼于4个象限、黄斑区和黄斑外区MERG a波、b波潜伏期及b波振幅密度、振幅之和均明显低于正常对照组(P<0.01);脱离区、非脱离区和正常眼的 MERG b波振幅密度分别为(3.44±2.85)、(6.34±3.31)、(21.32±6.48)nV/deg²,三者之间的差异均有非常显著性意义(P<0.05)。 结论 多焦ERG能客观定量评价RD的黄斑部、后极部的脱离区和非脱离区的视功能。(中华眼底病杂志,2000,16:244-247)     

The impact of fixation on the multifocal electroretinogram

There are a number of variables which can influence the quality of multifocal ERG waveforms. In common with visual field measurements, fixation quality may be an important parameter on the integrity of the acquired data. A low cost, fixation-monitoring device was used to assess fixation quality on a group of normal volunteers. Data was successfully acquired while five subjects viewed a fixation target for a period of time equal to that of a single multifocal recording segment. The target was presented on a stationary grey background and as the central fixation mark on a 61-element multifocal flicker stimulus. The results show no significant difference with or without the flickering pattern. The percentage of samples falling within 1.2° of the point of fixation was 51%. This suggests that fixation quality is adequate for scaled stimuli where the central element subtends 2.4°. High resolution stimuli of less than 2.4° may be more susceptible to fixation fluctuations during the recording process.     

视网膜色素变性的多焦视网膜电图

目的研究视网膜色素变性（ＲＰ）的多焦视网膜电图（ＥＲＧ）特性和评价多焦ＥＲＧ应用价值。方法检测了 １２例（２４眼）ＲＰ患者的多焦 ＥＲＧ,测试野为２６．６°×２２．１°,记录 １０３个部位的反应,同时检测全视野 ＥＲＧ。结果ＲＰ眼在各个环的ａ波和ｂ波潜伏期、ｂ波振幅密度和振幅之和均较正常值有显著延长和降低（Ｐ＜０．０５或Ｐ＜０．０１）。５０％患眼在第１环可记录到潜伏期正常、振幅密度和总和均降低的ｂ波,而７５％患眼的全视野ＥＲＧ呈平坦反应。结论 多焦ＥＲＧ能更有效地评价ＲＰ的黄斑区功能。     

The effect of filter bandwidth on the multifocal electroretinogram

The effect of filter bandwith on the multifocal electroretinogram was assessed by means of theoretical calculation, electronic simulation and real multifocal electroretinogram recordings. Waveform distortion by high-pass filtering on simulated square waves, normal electroretinogram waveforms and negative electroretinogram waveforms was demonstrated. The theory of the effect of differentiation on electroretinographic waveform shape by electronic filtering indicates that little effect would be observed by changing the input filter cut-off for normal electroretinographic waveform shapes. However, negative electroretinogram waveforms are differentiated when the high-pass filter setting is increased. The differentiation effect artificially recreates a positive component that could be mistaken as a b-wave component. To eliminate this effect when recording multifocal electroretinograms, a high-pass filter setting of less than 1 Hz should be used to preserve the true electroretinographic waveform shape.     

Effects of refractive blur on the multifocal electroretinogram

A significant difference in the response density of the MF-ERG response has been suggested for every 2 diopter change of refraction. The influence of refractive blur on the MF-ERG was studied in 8 healthy volunteers using either the VERIS™ system (Group A: n=5) or Retiscan™ (Group B: n=3). For each eye recordings were obtained with a corrective lens of −3 dpt, 0 dpt, +3 dpt and +6 dpt placed in front of the contact lens electrode. The viewing distance was adjusted to compensate for the induced changes in the retinal image size. When the changes in retinal image size due to the refractive lens were compensated for, no influence due to refraction was observed in either latencies or amplitudes of (KI (P>0.05). This held true for the central response average (four degrees) as well as for the outer 6–25 degrees. In KII.1 only the peripheral amplitudes of Group B showed an influence due to refraction (P≤0.05). This may be due to adaptation as the recordings of group B were obtained in succession. As expected, significant differences were observed when the recordings obtained with the different systems were compared (P≤0.05). This revised version was published online in July 2006 with corrections to the Cover Date.     

The multifocal electroretinogram in X-linked juvenile retinoschisis

To measure and compare the multifocal electroretinography in normal control and X-linked juvenile retinoschisis, 13 cases (13 right eyes) of normal control and nine cases (17 eyes) of X-linked juvenile retinoschisis were measured with VERIS Science 4.0. Four cases (eight eyes) out of the nine retinoschisis cases were tested with Ganzfeld ERG at the same day. The results showed statistically significant difference of average response densities and latencies in six ring retinal regions between the normal control and retinoschisis. The trace array and 3-D topography of multifocal ERG showed multi-area amplitude decrease with absence or reduction of central peak amplitude in patients with retinoschisis. The P₁/N₁ ratio of multifocal ERG average response densities in six ring retinal regions was different from the b/a ratio of Ganzfeld ERG. The multifocal ERG and Ganzfeld ERG each had its advantage in the diagnosis of retinoschisis.     

正常人多焦视网膜电图的特征

目的:探讨正常人多焦视网膜电图(multicalelec-troretinogram,mERG)在视网膜的分布特征,以获得正常参考值。方法:应用法国Metrovision公司生产的VisionMonitor视觉诱发系统检测15例(24眼)正常人mERG,检测视野的水平视角±30°,垂直视角±23°,采用ERG-jet接触镜电极,于5min记录61个视网膜部位的反应。结果:黄斑中心凹N1波、P1波、N2波的振幅密度最大,分别为(47.26±19.51)nV/deg2,(118.22±45.08)nV/deg2,(127.55±38.83)nV/deg2,向周边振幅密度逐渐降低;N1波、P1波的颞侧振幅密度较鼻侧大;P1波、N2波的颞上区振幅密度较鼻下区大。黄斑中心凹P1波、N2波的潜伏期均较其他各区缩短。结论:mERG的各波振幅密度与视网膜感光细胞的分布基本一致,能准确、客观的反映视网膜各部位的功能。     

小型猪多焦视网膜电图的记录方法及特点

目的 研究小型猪多焦视网膜电图（multifocal electroretinogram,mfERG）的记录方法及特点.方法 应用罗兰电生理系统中的RETI scan软件对5只小型猪正常眼行mfERG检查,记录波形成分并进行统计学处理.结果 对P1波各项指标进行统计学分析见第1～6环反应密度逐渐下降,波幅值逐渐升高;N1波幅值和潜伏期差异无统计学意义（P＞0.05）;P1波上半野反应密度和波幅值较下半野高,峰潜时值较短;N1波上半野波幅值较下半野高,峰潜时值较长.结论 应用mfERG对实验动物进行检查,可以客观评估动物视网膜后极部功能变化.     

Oscillatory potentials of multifocal electroretinogram retinopathy

Purpose: To investigate the physiological function in the posterior pole of the retina in eyes with preproliferative diabetic retinopathy using the oscillatory potentials (OPs) of the multifocal electroretinogram (mfERG). Methods: Multifocal ERGs were recorded from 61 eyes of 61 patients with preproliferative diabetic retinopathy (pre-PDR) and 16 eyes of 16 age-similar normal control subjects. The amplitudes and implicit times of the first positive component, P1, and the OPs of the mfERGs, recorded with a slow m-sequence, from diabetics were compared with those in normal control subjects. Among the 61 eyes, the mfERGs were recorded before and after panretinal photocoagulation (PRP) in 19 eyes of 19 patients. Results: The amplitudes of P1 and OPs were significantly smaller in all tested areas in the diabetics as compared with those in the normal subjects, and the degree of reduction was greater for the OPs than P1. The implicit times of P1 and OPs were significantly delayed in the diabetics in the peripheral tested regions (20–40°) but not in the central area. After PRP, the amplitudes of P1 were markedly reduced in all areas tested; however, the changes of the P1 implicit time were not significant. The amplitudes of the OPs were significantly reduced in the peripheral regions after PRP; however, the changes in the implicit times were not significant. Conclusions: These results indicate that retinal function in the posterior pole is markedly impaired in eyes with pre-PDR. PRP altered the mfERGs significantly, however, the reductions were limited to the amplitude.