先天性静止性夜盲的多焦ERG特征

目的探讨先天性静止性夜盲眼在不同离心度多焦视网膜电图(mERG)振幅和潜伏值改变与先天性静止性夜盲(CSNB)的关系.方法应用mERG技术对CSNB患者8人14眼进行检测,随机选用视力1.0以上、年龄匹配的正常人14眼作为对照.MERG检测选用103个六角形刺激成分,采用刺激频率75 Hz的短m序列对后极部30°视网膜进行刺激和同步记录,分析6个不同离心环一级反应的b波反应密度和a,b波潜伏值以及受刺激视网膜提取的b波反应密度和及各波潜伏值和.结果从CSNB提取的mERG反应的1环及2环的b波反应密度值与对照组相比轻度下降,但无统计学差异(P＞0.05),而3～6环各环b波反应密度值与对照组相比明显下降(P＜0.01).此外,患病组从1～6环各环提取的mERG反应的a,b波潜伏值较正常对照组严重下降(P＜0.01),且异常程度较b波反应密度值更严重.患病组后极部30°范围视网膜b波反应密度和及a,b波潜伏值和较对照组明显下降.结论MERG能客观评价CSNB局部视网膜功能损害程度,mERG潜伏值的延长较其振幅改变和心理物理学的视野检查更能揭示CSNB功能改变的特征.     

多焦视网膜电流图用于近视眼视网膜功能的研究

目的应用多焦视网膜电流图(mltifocal electroretinogram,mERG)探讨不同程度近视眼不同部位视网膜的功能状态,并与正常人作比较,评价其差异。方法收集我院眼科门诊就诊的18～32岁的病例68例(101眼),分为中低度近视组(23例40眼)、高度近视组(24例40眼)和正常对照组(21例21眼)。所有病例均应用德国罗兰公司的mERG仪记录各环N1波、P1波的潜伏期和振幅密度,再比较3组各检查结果之间的差别。结果 3组N1波和P1波的振幅密度在第1环最大,随离心度的增加而逐渐降低;潜伏期在第1环最小,随离心度增加而逐渐延长。经统计学处理,高度近视组N1波和P1波各环的振幅密度较正常对照组及中低度近视组低,差异均有统计学意义(均为P<0.05);中低度近视组与正常对照组N1波和P1波各环的振幅密度比较,差异均无统计学意义(均为P>0.05)。高度近视组N1波P1波第1环潜伏期较正常对照组及中低度近视组延长,差异有统计学意义(P<0.05),其余组间比较差异均无统计学意义(P>0.05)。结论高度近视眼mERG各环振幅密度较正常眼下降,1环潜伏期较正常眼延长;中低度近视眼与正常眼振幅密度及潜伏期无明显变化。     

不同年龄正常人多焦视网膜电流图的波形特征

目的了解不同年龄正常国人多焦视网膜电流图(mERG)的波形特征,为mERG的临床应用提供参考.方法正常志愿者35人50眼按年龄分为"＜20岁组"、"20～50岁组"、"＞50岁组"共三组,应用VERIS Science4.0视觉诱发反应图象系统进行检查.结果各年龄组正常眼mERGa、b、c波振幅在黄斑部最大,变异也最大,远离黄斑部各区逐渐减小;鼻侧a、b、c波振幅均比颞侧大,而上方与下方差别无显著性;年龄不同,正常眼mERG a、b、c波振幅和潜伏期均存在一定差异.结论mERG能在特定时间段内客观地对被检测部位每一局部区域视网膜功能进行分析,临床应用须考虑年龄因素的影响.     

黄斑病变患者多焦视网膜电图的变化

目的:观察黄斑病变多焦视网膜电图穴mERG雪特点,探讨mERG在黄斑功能测定中的有效性。方法:应用德国罗兰视觉诱发反应成像系统,对黄斑病变71 眼与正常人48眼进行mERG测定,记录103个视网膜部位的一阶反应(first orderkernel,FOK)比较分析视网膜后极部不同区域a波和b波的平均反应密度值和潜伏期,并观察其三维图的改变。结果:黄斑病变患者1～3环a、b波平均反应密度下降,与正常值比较有显著差异。5、6环平均反应密度下降,无显著差异。1～6环a、b波平均潜伏期较正常组明显延长,三维图形上主要特征为中心凹及黄斑振幅明显降低,严重者反应呈平坦。结论:mERG能客观地对黄斑病变局部视网膜功能进行定量定位测定,是评价黄斑病变的一种有效客观检测手段,为疾病诊断和治疗效果客观的测定提供了一种有效方法。     

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)     

正常眼多焦视网膜电图特征的初步探讨

目的 :初步分析正常人眼多焦视网膜电图 (m ERG)测量值 ,并探讨正常眼视网膜后极部不同部位的电生理功能。方法 :对 19例 (2 5眼 )散瞳正常眼作多焦视网膜电图检查 ,记录 6 1个部位反应波形图 ,分析视网膜后极部不同区域的a波 (第 1个负波 )和b波 (第 1个正波 )的潜伏期、振幅值及振幅密度。结果 :视网膜后极部中心环 (第 1环 )振幅密度为最高 ,a波为 (33.92± 18.95 )nV/deg2 ,b波为 (6 8.78±19.84 )nV/deg2 ,随着离心度的增加 ,各振幅密度逐渐下降 ,差异有显著性 (P <0 .0 1)。a波及b波潜伏期、振幅及振幅密度在四个象限的差异均无显著性 (P >0 .0 5 )。结论 :多焦视网膜电图能客观、定位、定量地测定视网膜后极部不同部位的视功能 ,其测定的正常值为临床研究提供了参考数值     

正常人闪光视网膜电图的特征

目的:探讨闪光视网膜电图(flash electroretinogram,F-ERG)在正常人的变化规律,以获得正常参考值.方法:应用法国Metrovision公司生产的Vision Monitor视觉诱发系统检测正常人53例73眼.F-ERG的5个标准反应,包括暗适应25dB弱光刺激时的反应(来自于视杆细胞)、暗适应odB强光刺激时的反应、振荡电位、明适应白色标准闪光刺激时的反应(来自于视锥细胞)和明适应快速重复闪烁光刺激的反应.按照10岁为一年龄组分成4组:20～29岁,20眼;30～39岁,22眼;40～49岁,19眼;50～60岁,12眼.比较4个年龄组振荡电位总振幅和a波、b波的振幅及潜伏期.结果:F-ERG暗适应25dB弱光刺激时a波无明显反应,b波潜伏期为1102±113ms,振幅为226.7±492μV;暗适应odB强光刺激时a波潜伏期为263±12ms,振幅为.205.4±40.1μV,b波潜伏期为49.3±2.3ms,振幅为481.2±81.2μV;明适应白色标准闪光刺激时a波潜伏期为23.0±1.6ms,振幅为-23.4±9.1μV,b波潜伏期为38.8±1.8ms,振幅为77.4±21.2μV;明适应快速重复闪烁光刺激b波的振幅为122.1±27.51μV;震荡电位总振幅为112.6±28.2μV.随着年龄的增加,振荡电位总振幅和其余4个标准反应的b波振幅逐渐降低,a波振幅与年龄的增加无明显相关性,50～60岁年龄组a、b波的潜伏期较其他组延长,但各年龄组两两比较无显著统计学差异(P＞0.05).结论:确定了正常人F-ERG的5个标准反应的正常值,并比较了振荡电位总振幅和a,b波振幅及潜伏期与年龄的关系,振荡电位总振幅和b波振幅随着年龄的增加逐渐降低,a波振幅与年龄的增加无明显相关性,50-60岁年龄组a,b波的潜伏期较其他组延长,但各年龄组两两比较无显著统计学差异(P＞0.05).     

中心性浆液性视网膜脉络膜病变的多焦视网膜电图特征

目的 探讨中心性浆液性视网膜脉络膜病变(CSC)的多焦视网膜电图(mERG)特征。方法 对18例(18眼)CSC患者的患眼和对侧眼做多焦视网膜电图检查，记录61个部位反应，比较分析视网膜后极部不同区域的a波(第1个负波)和b波(第1个正波)平均反应振幅密度。结果 CSC眼组1～3环a波和b波平均反应振幅密度明显低于正常对照组，两者之间差异有显著性意义。结论 多焦视网膜电图能对CSC局部视功能进行定量定位测定，为疾病诊断和治疗效果监测提供重要手段。     

不同程度近视眼LASIK术前及术后多焦ERG的变化

目的 对行准分子激光原位角膜磨镶术（LASIK）的不同程度近视患者术前及术后3个月均测定黄斑区不同部位的视网膜功能,然后评价其差异。方法 前瞻性对照研究。2012-2013年期间收集沧州市中心医院屈光门诊18～32岁的近视患者91例（169眼）,分为低度近视组30例（58眼）,中度近视组32例（57眼）和高度近视组29例（54眼）。所有患者均经过严格的术前检查,具备手术条件,术前及术后均应用德国Roland公司的多焦视网膜电流图（mERG）仪RETI-SCANK系统记录近视患者黄斑区mERG的一阶反应,分别测定各环N1、P1波的潜伏期和振幅密度。采用单因素方差分析和配对t检验比较3组术前及术后3个月各检查结果之间的差别。结果 各组术前及术后mERG的振幅密度在第1环最大,随离心度的增加均逐渐降低。潜伏期在第1环最小,随离心度增加均逐渐延长。不同程度的近视组术前及术后的mERG相比较发现：3组mERG各环的振幅密度及潜伏期在术前及术后比较,差异均无统计学意义。结论 LASIK对于近视眼眼底黄斑区视网膜功能没有影响。     

重度非增生性与增生性糖尿病视网膜病变多焦视网膜电图一阶函数核的特征分析

目的对比并分析糖尿病视网膜病变(diabetic reti-nopathy,DR)重度非增生期及增生期的多焦视网膜电图(mul-tifocal electroretinogram,mERG)一阶函数核的变化特征。方法选取DR患者46例72眼分为2组:一组为重度非增生性糖尿病视网膜病变(non-proliferative diabetic retinopathy,NPDR)患者23例38眼,另一组为增生性糖尿病视网膜病变(proliferative diabetic retinopathy,PDR)患者23例34眼。设立对照组为正常健康人23例34眼。采用罗兰的多焦视觉电生理检查仪进行mERG一阶函数核反应检查,提取数据后分析比较2组患者mERG1~5环的N1波、P1波的振幅密度值及峰时值。结果PDR组的N1波和P1波的振幅密度值比NPDR组下降,第1环的差异均有显著统计学意义,2~5环N1波的差异无统计学意义,P1波的差异有统计学意义;PDR组的N1波和P1波的潜伏期比NPDR组延迟,2种波形第1环的差异均无统计学意义,2~5环的差异有统计学意义(N1波4环除外)。结论DR从非增生期进入增生期,mERG一阶函数的N1和P1波在黄斑中心凹区振幅密度值下降明显,而在黄斑区外视网膜则以潜伏期的延长为明显。N1和P1波的振幅密度值对反映视细胞功能更为敏感,而潜伏期则可能与视网膜缺血的关系相对密切。     

Inter-ocular and inter-session reliability of the electroretinogram photopic negative response (PhNR) in non-human primates

PURPOSE: To assess the inter-ocular and inter-session reliability for a range of parameters derived from the photopic electroretinogram (ERG) in a group of normal non-human primates. METHODS: Inter-ocular differences for photopic ERGs were assessed in a group of normal anesthetized adult rhesus monkeys (Macaca mulatta, n=29); inter-session reliability was assessed for 23 eyes of 23 animals tested 3 months later. Signals were acquired using Burian-Allen contact lens electrodes, whereby the contralateral cornea served as a reference. Photopic ERGs were elicited using red Ganzfeld flashes (-0.5-0.67 log photopic cd.sm(-2)) on a rod suppressing blue-background (30 scotopic cdm(-2)). Measurement reliability was established for a-wave, b-wave, photopic negative response (PhNR) and oscillatory potential (OP) amplitudes, as well as for their implicit times, by calculation of the 95% limits-of-agreement (LOA) and the coefficient-of-variation (COV) for each parameter. RESULTS: OP and a-wave amplitudes increased with intensity up to 0.67 log photopic cd.sm(-2), following a typical saturating function, whereas b-wave and PhNR amplitudes both declined above 0.42 log photopic cd.sm(-2). Inter-session variability was greater than inter-ocular variability. The inter-session COVs for PhNR amplitude (10-20%) were similar to the other photopic ERG components (a-wave: 12-17%, b-wave: 12-17%, OPs: 13-19%). Inter-session LOAs were also similar across components, but on average, were smallest for responses to moderate intensities (0.0-0.42 log photopic cd.sm(-2)). CONCLUSION: In non-human primates, the 95% LOA for inter-session measurements of the photopic ERG a-wave, b-wave, OPs and PhNR are all similar. Inner-retinal damage may best be measured using the PhNR amplitude for moderately bright stimulus intensities. B-wave and PhNR amplitudes for brighter flashes are smaller and more variable. The ratio of PhNR:b-wave amplitudes manifests smaller variability and may therefore be useful for detection of selective PhNR loss.     

Empiric limits of rod photocurrent component underlying a-wave response in the electroretinogram

The corneally recorded rod photocurrent component (photoresponse) underlying the a-wave feature of the electroretinogram was analyzed. The results set empiric limits on critical photoresponse variables. Measurements were obtained from four normal adult subjects on a-wave amplitude, a-wave velocity, b-wave amplitude, b-wave implicit time and b-wave height above baseline. At high intensity, interference from the b-wave component was minimized and the amplitude of the saturated photoresponse component was approximated by the a-wave feature. At lower intensities, the a-wave feature represented progressively less of the underlying photoresponse amplitude. Photoresponse amplitude saturation was signaled by the abrupt slowing of the rate of decline of b-wave peak latency and occurred at an intensity about 2.5 log units above the first appearance of the b-wave. At the intensity of photoresponse saturation, the peak amplitude of the a-wave feature was only about 25% of the maximum amplitude of the underlying photoresponse component. A-wave leading edge velocity was found to increase up to 3 log units above the intensity of photoresponse amplitude saturation and to provide a good estimate of photoresponse velocity at higher intensities. A cascaded low-pass filter model with modifications to accommodate amplitude and timing nonlinearities was used to generate a set of probable underlying photoresponses from the analysis of a-wave amplitude and velocity. Movement of the a-wave leading edge to the left at higher intensities in algebraic combination with a static b-wave leading edge above the intensity of photoresponse amplitude saturation was found to explain the second rise of the b-wave amplitude function and the decline of b-wave amplitude above baseline at high intensities. This analysis provides a basis for modeling the underlying photoresponse on a biochemical level and for interpreting photoreceptor damage in disease states.Supported in part by a grant from the Ethel Brown Foerderer Foundation, Children's Hospital of Philadelphia, and by a grant from the Nina and Paul MacKall Trust.     

1型糖尿病患者早期视觉诱发电位和视网膜电图分析

目的：探讨1型糖尿病患者早期的视觉电生理变化情况,分析糖尿病视网膜病变的早期与视觉诱发电位和视网膜电图改变的相关性。
　　方法：观察组60例1型糖尿病患者,男女比例均等,平均年龄19.42依7.78岁,病程小于5a,矫正视力5.0,平均空腹血糖7.8依3.6mmol / L。进行图形视觉诱发电位和闪光视网膜电图检查。对照组60例正常人,男女比例均等,平均年龄17.2依6.52岁,矫正视力5.0,进行图形视觉诱发电位和闪光视网膜电图检查;记录两组 PVEP 参数P100波潜伏期和 P100波振幅值,FERG 参数 a 波潜伏值、b 波潜伏期、a 波振幅值、b 波振幅值。
　　结果：观察组的参数 P100波振幅值、P100波潜伏期与对照组比较,有显著统计学意义(P<0.01),均有振幅值降低,潜伏期延长;观察组的参数 a 波潜伏期、a 波振幅值、b波潜伏期、b 波振幅值与对照组比较差异有显著统计学意义(P<0.01);观察组平均空腹血糖控制稳定,PVEP P100的振幅值、FERG a、b 波的振幅值与糖尿病程无关,而 PVEP P100的潜伏值、FERG a、b 波的潜伏值与糖尿病程有关。
　　结论：图形视觉诱发电位提示糖尿病患者视神经元损伤较为敏感;闪光视网膜电图是早期发现糖尿病患者视网膜 Müller 细胞和双极细胞损害的理想手段;图形视觉诱发电位参数 P100波振幅值、闪光视网膜电图参数 b 波振幅值可能是糖尿病视网膜临床前期最敏感的诊断指标。     

Focal macular electroretinogram in high myopia

To investigate early changes of the macula in eyes with myopia, we compared 66 eyes with high myopia with 76 normal eyes by recording focal macular electroretinogram (ERG). The eyes with high myopia were divided into two groups; eyes showing only tigroid fundus (group 1) and those associated with posterior staphyloma involving the macula (group 2). The visual acuity of groups 1 and 2 was 1, 0 or better and 0.8 or better, respectively. The amplitude of the a-wave, b-wave in group 1 was significantly smaller than that of normal eyes, however the peak latency was within the normal range. The amplitude of a-wave, b-wave and oscillatory potentials in group 2 was significantly smaller and the peak latency was significantly longer than those in group 1. The abnormal amplitude with normal peak latency in group 1 suggests some reduction of numbers of cones, which is considered to be an early pathologic change in the macula with high myopia. The more reduced amplitude with delayed peak latency in group 2 suggests that, in the advanced stage, the macular pathologic finding includes some quantitative damage as well as further reduction of macular cones.     

Association of electroretinogram and morphological findings in branch retinal vein occlusion with macular edema

The objective of this study is to evaluate the relations among electroretinogram parameters (cone a-wave, cone b-wave, and 30-Hz flicker), retinal thickness, and retinal volume in patients with branch retinal vein occlusion (BRVO) and macular edema. We prospectively examined 33 patients (33 eyes) with BRVO and macular edema. The amplitude and implicit time of the a-wave cone, b-wave cone, and 30-Hz flicker were calculated automatically from the ERG. Retinal thickness and volume were measured by optical coherence tomography (OCT) in nine macular subfields. Then, correlations between the ERG parameters and morphological parameters were analyzed. The 30-Hz flicker amplitude was significantly smaller in the eyes with BRVO and macular edema than in the unaffected contralateral eyes. Thirty-hertz flicker and cone b-wave implicit times were significantly longer in the eyes with macular edema than in the unaffected eyes. The implicit time of the cone b-wave was correlated with both retinal thickness and retinal volume in the temporal subfields. Thirty-hertz flicker amplitude was correlated with both retinal thickness and volume in the temporal and superior outer (site of occlusion) subfields, while 30-Hz flicker implicit time was correlated with retinal thickness and volume in the outer temporal subfield. Multiple regression analysis demonstrated that the retinal thickness and volume of the temporal subfields were significant “determinants” of the implicit time for the cone b-wave and 30-Hz flicker, as well as the 30-Hz flicker amplitude. These findings suggest that OCT parameters of the temporal region may reflect postreceptoral cone pathway function in BRVO patients with macular edema.     

The human focal electroretinogram as a function of stimulus area

Focal electroretinograms to on-off luminance modulation (2.7 Hz) of uniform fields with a different area (144-2.25 deg²) centered on the fovea were recorded in two young normal subjects. The electroretinogram responses typically consisted of an a-wave, a b-wave, a PIII component and a d-wave. The concentric reduction of the test field size caused progressive amplitude decrement of all components, while their response density increased. The spatial summation properties of the b-wave differed from those of the a-wave, PIII component and d-wave so that the relative contribution of the b-wave to the electroretinogram waveform depended on the stimulus area. For a critically small field size, the electroretinogram was dominated by the PIII and d-wave components. Only these two electroretinogram components displayed a density profile that could be compared with that of cone distribution.     

Clinical and electrophysiological findings in three patients with toluene dependency

We recorded the electrophysiological findings of three patients with toluene dependency who developed visual disturbance. In five of six eyes the peak latency of the pattern visual evoked cortical potential was prolonged as compared with that of normal subjects. The amplitude and the latency of the a-wave of the electroretinogram were decreased in five of the six eyes and prolonged in four. Those of the b-wave in patients were less affected than the a-wave: in one of six eyes the amplitude of the b-wave was decreased and in two the b-wave latency was prolonged. The amplitudes of the oscillatory potentials were decreased in three of six eyes. The electroretinogram was investigated in one patient and showed little increase in amplitude during light stimulation, so that a lowered light peak to dark trough ratio was obtained.Our findings suggest that any part of the visual pathway, including the distal part of the retina and retinal pigment epithelium, might be impaired by the chronic inhalation of toluene vapors.Abbreviations EOG Electrooculogram - ERG Electroretinogram - L/D light peak to dark trough ratio - OP Oscillatory potential - VECP Visual evoked cortical potential     

糖尿病性黄斑水肿视网膜功能定量研究

目的:应用多焦视网膜电图评估糖尿病性黄斑水肿的视网膜功能.方法:选取2010-03/2014-03我院眼科经眼底血管造影检查确诊为糖尿病性黄斑水肿的患者30例48眼为观察组(其中局限性水肿18眼,弥漫性水肿24眼,囊样水肿6眼),选取视力0.8以上,经裂隙灯显微镜检查均未发现异常,全身情况无异常者15例30眼为对照组,两组研究对象均行多焦视网膜电图检查,并对其结果进行统计学分析.结果:糖尿病性黄斑水肿组多焦视网膜电图中心凹、黄斑区、黄斑外区a、b波的振幅密度与对照组相比均差异存在统计学意义(P＜0.01);中心凹处观察组和对照组a波的振幅密度分别为25.2±10.48、37.93±7.19nv/deg2,b波的振幅密度分别为77.16±27.97、113.42±11.79nv/deg2;黄斑区观察组和对照组a波的振幅密度分别为14.27±4.99、27.42 ±2.86nv/deg2,b波的振幅密度分别为43.14±14.77、69.99±10.07 nv/deg2;黄斑外区观察组和对照组a波的振幅密度分别为7.82±2.79、11.46±1.54nv/deg2,b波的振幅密度分别为19.85±6.5、31.56±6.0nv/deg2.中心凹处、黄斑区及黄斑外区多焦视网膜电图a、b波振幅密度在局限性黄斑水肿组与弥漫性黄斑水肿组和囊样黄斑水肿组间均存在统计学意义(P＜0.01).结论:糖尿病性黄斑水肿的多焦视网膜表现为a、b波振幅密度下降,潜伏期延长,振幅密度比潜伏期敏感.     

Relationships between the electroretinogram a-wave,b-wave and oscillatory potentials and their application to clinical diagnosis

The electroretinogram is the electrical response of the retina to a light stimulus. The amplitude and temporal pattern of its components, the a-wave, the b-wave and the oscillatory potentials, depend on the functional integrity of the retina, on the intensity of test flash reaching the retina and on the ambient illumination. The latter contributions to the normal variability in the electroretinogram can be circumvented by constructing the relationships between the different electroretinogram waves. The electroretinogram responses were recorded from 18 dark-adapted subjects with normal vision. The slope of the a-wave and the amplitude of the b-waves were measured in the time domain. The oscillatory potentials were isolated by a digital filter and were transformed to the frequency domain for quantitative measurement. The relationship between each pair of variables could be fitted by linear segments. Our findings suggest that this mode of electroretinogram analysis can be useful in localizing the site of action of retinal disorders and that the relationship between the a-wave slope and the power density of the oscillatory potentials is a useful index for identifying disorders of the inner retina.