正常人与青光眼患者多焦视觉诱发电位检测的比较

目的比较正常人和青光眼患者多焦视觉诱发电位（mfVEP）的差异。方法使用VERIS多焦视觉电生理仪，采用四通道法测量正常受试者22例41眼及青光眼患者22例40眼的mfVEP，将正常人及青光眼患者所得结果取反应振幅的信噪比值（SNR），逐一刺激单元进行比较。结果青光眼患者的mfVEP显著低于正常人，尤其是上半视野中具有显著性差异的单元多，与青光眼患者视神经病理性损害的方式一致。结论mfVEP可应用于青光眼患者的检测，可以在临床推广应用。     

多焦视诱发电位的双眼对称性分析

目的 观察正常人多焦视诱发电位(mfVEP)的双眼对称性。 方法 应用VERIS Science 4.0视觉诱发反应图像系统对36名正常人的72只眼进行mfVEP测试，刺激图形为带图形的飞镖盘，对应的视角为25°。图形中有60个小块，每个小块包括4×4个黑白相间的格子，由二元伪随机m-序列控制其黑白翻转形成视觉刺激。 结果 左右眼各对应象限的P1波潜伏期及振幅配对 t 检验显示差异无统计学意义。双眼同侧视野的潜伏期与振幅的数据差异大于相应视野象限的数据差异。右眼或左眼4个象限组间比较显示双眼各自鼻上与颞下、鼻下象限P1波潜伏期之间差异有统计学意义，振幅方面仅左眼颞上与颞下象限之间差异有统计学意义。 结论 正常人双眼mfVEP以视网膜对称性优于视皮层的对称性。 (中华眼底病杂志, 2006, 22: 42-44)     

黄斑病变的多焦视觉诱发电位检测

目的记录几种类型黄斑病变的多焦视觉诱发电位(mfVEP)变化，探讨mfVEP测试黄斑病变视功能变化的可行性。方法采用VERIS多焦视觉电生理仪测量31只黄斑病变眼和32只正常对照眼的mfVEP，将测试野分为上下两半，再分别由内向外分为3个环。两组对比分析每环mfVEP的二阶一次反应。结果黄斑病变眼上下半视野的中央环mfVEP的P1波潜伏期延长，N1-P1及P1-N2振幅降低，以下半视野的改变更为明显。结论mfVEP可以检测出黄斑病变的视功能损害。     

原发性青光眼不同区域多焦视觉诱发电位的研究

目的:比较正常人和原发性青光眼患者不同分区的多焦视觉诱发电位(multifocalvisualevokedpoten-tial,mfVEP),评价mfVEP在青光眼诊断中的作用。方法:采用法国VisionMonitor多焦视觉电生理仪的二阶kernel技术检测21例32只正常对照眼、37例58只原发性青光眼的mfVEP,将青光眼mfVEP振幅均方根(rootmeansquare,RMS)及潜伏期与正常对照眼行不同分区的比较。结果:正常眼mfVEP的RMS值个体间变异大(变异系数CV=43.05%)。青光眼mfVEP的RMS值在上下半视野,鼻上、颞上、鼻下、颞下四个象限及各个环形分区均较正常对照眼小,且在0～10°环形区域及鼻上象限差异有显著性意义(P<0.05),二者各个区域的潜伏期无差异。结论:正常人mfVEP个体间变异性大;青光眼患者mfVEP振幅较正常人下降,且在中央区域及鼻上象限更为显著。     

多焦视觉诱发电位诊断青光眼的价值

目的:记录正常人和青光眼患者的多焦视觉诱发电位(multifocalvisualevokedpotential,mfVEP),评价mfVEP在青光眼诊断及病情监测中的价值。方法:采用法国VisionMonitor多焦视觉电生理仪的二阶kernel技术检测21例32只正常对照眼、37例58只原发性青光眼的mfVEP,比较同一个体双眼间的振幅均方根(rootmeansquare,RMS),并分析原发性青光眼患者的mfVEP与Humphrey视野(Humphreyvisualfield,HVF)的相关性。结果:正常人RMS值与年龄、眼别无关,但女性RMS值大于男性,差异有显著性意义(P<0.05);正常眼mfVEP的RMS值个体间变异大(变异系数CV=43.05%),但同一个体双眼间反应差异不大;双眼损害程度相近的青光眼,双眼mfVEP的RMS值无明显差异(P=0.251);双眼损害程度不一的青光眼,双眼RMS值不同(P=0.024);mfVEP的RMS值总和与视野的平均缺损值(meandefect,MD)具有较强的相关性(rs=-0.487,P=0.000)。结论:正常人mfVEP个体间变异性大,但同一个体双眼间反应差异不大。对于青光眼双眼损害程度不一或单眼损害者,进行双眼间mfVEP非对称分析,可以早期发现青光眼损害并进行病情监测。青光眼患者的mfVEP振幅与视野平均缺损值相关性较好,在一定程度上可以弥补主观视野检查的不足。     

视网膜色素变性的多焦视诱发电位及其与视野的比较

目的:探讨视网膜色素变性(retinitispigmentosa,RP)的多焦视诱发电位(multifocalvisualevokedpotential,mfVEP)特性及评价mfVEP作为RP客观视野检测方法的可能性。方法:检测12例(19只眼)RP患者和15例(30只眼)正常人的mfVEP,刺激野为带图形的含60个小块的飞镖盘,单侧对应视角为26°。比较RP患者与正常人mfVEP的二阶函数核第一片的P1波的振幅。对RP患者还进行30°阈值视野检测,检验对应区域mfVEP的P1波振幅总和与视野光敏感度总和的相关性。结果:与正常人相比,RP患者各环的mfVEP的P1振幅总和的降低均有显著意义(P<0.05)。除了下1环和下2环外,其余各环mfVEP的P1振幅总和与视野光敏感度总和均有显著相关(P<0.05)。结论:mfVEP与视野间存在着一定的相关性,mfVEP可作为评价RP患者视功能的客观方法。     

多焦视觉诱发电位用于诊断视神经病变

目的:探讨多焦视觉诱发电位在视神经病变诊断中的应用价值.方法:对15例视神经病变患者行常规眼科视力、裂隙灯检查、眼底检查、Goldmann眼压测定、眼底荧光血管造影、视野和mfVEP检查.对受检者双眼mfVEP检查的波形结果进行相互比较,并与视野检查结果进行相互比较及对应一致性分析.结果:在所有视神经病变眼均检测到明显的mfVEP波形改变,其与视野的改变具有对应一致性.部分视神经病变眼局部mfVEP波形改变同视野改变略有差别.结论:mfVEP在视神经病变的诊断中具有独特的优势,有望成为一种视神经病变诊断的新方法.双眼间比较有助于发现单眼局部的视神经损害.     

正常人多焦视觉诱发电位的特征

目的 探讨正常人多焦视觉诱发电位（multifocal visual evoked potential，mf-VEP）的特征，为其临床应用提供正常参考值。 方法 应用VERIS Science^TM 4.0视觉诱发反应图像系统对37例正常人70只眼进行mf-VEP检测。刺激图形为包含60个小块的飞镖盘，对应的视角为25°，m-系列长度为2¹⁴-1，电极记录采用跨枕部双极记录法，放大器的放大倍数为100 K，通频带为3~100 Hz，通过VERIS软件分析mf-VEP的二阶一次 反应，并对不同刺激视野区域的mf-VEP分为上下1/2视野、4个象限视野组以及按年龄（≥5 0岁和<50岁组）、性别和眼别等分组进行比较。 结果 mf-VEP潜伏期和振幅反应密度在上下1/ 2视野差异有显著性的意义（P均<0.05）；4个象限视野分组比较，差异有显著性的意义（P<0.05）；≥50岁和<50岁年龄组组间比较，部分视野分区潜伏期延长（P<0.05）；女性潜伏期短于男性，差异有显著性的意义（P均<0.05）；双眼的潜伏期和振幅反应密度在各视野分区无明显差别（P均>0.05），具有一定的对称性。 结论 正常人mf-VEP具有一定的特征，能客观地反映不同视野部位的视觉诱发反应，可为临床应用提供正常参考值。 （中华眼底病杂志，2003，19：269-332）     

正常儿童多焦视觉诱发电位的特征

目的：分析正常儿童多焦视觉诱发电位（multifocalvisual evoked potential,mfVEP）的特征,为其临床应用提供正常参考值.方法：采用法国Vision Monitor视觉电生理检察系统对50例正常儿童66眼进行mfVEP检查,观察mfVEP的P1波和N2波振幅密度和潜伏期,分析性别、年龄、眼别对正常儿童mfVEP之P1波和N2波振幅密度和潜伏期的影响.结果：正常儿童mfVEP之P1波和N2波振幅密度在视野中央最大,随离心度的增加迅速减小;潜伏期在视野中央最小,一般随离心度的增加逐渐延长;性别与P1波的潜伏期有相关性（P=0.014）,与P1波的振幅密度及N2波的振幅密度和潜伏期没有相关性（P＞0.05）,而年龄、眼别与mfVEP之P1波和N2波的振幅密度和潜伏期无相关性（P＞0.05）.结论：正常儿童mfVEP具有一定特征,能够反映视野不同部位的视觉诱发反应,可为临床应用提供正常参考值.     

一项比较电生理学，心理生理学和青光眼损害结构测量的方法

目的：开发一种比较将多焦视觉激发电位（mfVEP）反应和用行为判定视野以及视神经乳头结构的方法。     

Dichoptic stimulation improves detection of glaucoma with multifocal visual evoked potentials

PURPOSE: To determine whether simultaneous binocular (dichoptic) stimulation for multifocal visual evoked potentials (mfVEP) detects glaucomatous defects and decreases intereye variability. METHODS: Twenty-eight patients with glaucoma and 30 healthy subjects underwent mfVEP on monocular and dichoptic stimulation. Dichoptic stimulation was presented with the use of virtual reality goggles (recording time, 7 minutes). Monocular mfVEPs were recorded sequentially for each eye (recording time, 10 minutes). RESULTS: Comparison of mean relative asymmetry coefficient (RAC; calculated as difference in amplitudes between eyes/sum of amplitudes of both eyes at each segment) on monocular and dichoptic mfVEP revealed significantly lower RAC on dichoptic (0.003 +/- 0.03) compared with monocular testing (-0.02 +/- 0.04; P = 0.002). In all 28 patients, dichoptic mfVEP identified defects with excellent topographic correspondence. Of 56 hemifields (28 eyes), 33 had Humphrey visual field (HFA) scotomas, all of which were detected by dichoptic mfVEP. Among 23 hemifields with normal HFA, two were abnormal on monocular and dichoptic mfVEP. Five hemifields (five patients) normal on HFA and monocular mfVEP were abnormal on dichoptic mfVEP. In all five patients, corresponding rim changes were observed on disc photographs. Mean RAC of glaucomatous eyes was significantly higher on dichoptic (0.283 +/- 0.18) compared with monocular (0.199 +/- 0.12) tests (P = 0.0006). CONCLUSIONS: Dichoptic mfVEP not only detects HFA losses, it may identify early defects in areas unaffected on HFA and monocular mfVEP while reducing testing time by 30%. Asymmetry was tighter among healthy subjects but wider in patients with glaucoma on simultaneous binocular stimulation, which is potentially a new tool in the early detection of glaucoma.     

Retinal symmetry of multifocal visual evoked potential in both eyes of normal subjects

Purpose: To analyze the retinal symmetry of muhifocal visual evoked potential(mfVEP) in both eyes of normal subjects.Methods: The monocular mfVEP in both eyes of 36 normal subjects (72 eyes) weretested with VERIS Science 4.0. The stimulus was the pattern reversal dart array con-sisted of 60 sectors each including 16 black-white reverse patterns. The visual stimu-lation was controlled by a binary pseudo-random m-sequence and subtended 25 de-grees of retinal region.Results: The nffVEP patterns between left and right eyes of each subject were similar,and P1 latency and amplitude in correspondent visual field quadrants between left and right eyes had no significant difference (P>0.05). The latency of superotemporal visual field quadrant in right eyes was shorter than that of superonasal visual field quadrant in left eyes, and the amplitude of superonasal visual field quadrant in right eyes was longer than that of superotemporal visual field quadrant in left eyes (P<0.05). The P1latency and amplitude among four visual field quadrants of each eye had significant difference (P<0.05). The P1 latency between the superonasal visual field quadrant and inferotemporal visual field quadrant or between the superonasal visual field quadrant and inferonasal quadrant visual field had significant differences in right or left eyes(P<0.05).Conclusion: The mfVEP of normal subjects exists retinal symmetry.     

Effect of recording duration on the diagnostic performance of multifocal visual-evoked potentials in high-risk ocular hypertension and early glaucoma

PURPOSE: To evaluate the effect on diagnostic performance of reducing multifocal visual-evoked potential (mfVEP) recording duration from 16 to 8 minutes per eye. METHODS: Both eyes of 185 individuals with high-risk ocular hypertension or early glaucoma were studied. Two 8-minute mfVEP recordings were obtained for each eye in an ABBA order using VERIS. The first recording for each eye was compared against single run (1-Run) mfVEP normative data; the average of both recordings for each eye was compared against 2-Run normative data. Visual fields (VFs) were obtained by standard automated perimetry (SAP) within 22.3+/-27.0 days of the mfVEP. Stereo disc photographs and Heidelberg Retina Tomograph images were obtained together, within 24.8+/-50.4 days of the mfVEP and 33.1+/-62.9 days of SAP. Masked experts graded disc photographs as either glaucomatous optic neuropathy or normal. The overall Moorfields Regression Analysis result from the Heidelberg Retina Tomograph was used as a separate diagnostic classification. Thus, 4 diagnostic standards were applied in total, 2 based on optic disc structure alone and 2 others based on disc structure and SAP. RESULTS: Agreement between the 1-Run and 2-Run mfVEP was 90%. Diagnostic performance of the 1-Run mfVEP was similar to that of the 2-Run mfVEP for all 4 diagnostic standards. Sensitivity was slightly higher for the 2-Run mfVEP, whereas specificity was slightly higher for the 1-Run mfVEP. CONCLUSIONS: If higher sensitivity is sought, the 2-Run mfVEP will provide better discrimination between groups of eyes with relatively high signal-to-noise ratio (eg, early glaucoma or high-risk suspects). But if higher specificity is a more important goal, the 1-Run mfVEP provides adequate sensitivity and requires only half the test time. Considered alongside prior studies, the present results suggest that the 1-Run mfVEP is an efficient way to confirm (or refute) the extent of VF loss in patients with moderate or advanced glaucoma, particularly in those with unreliable VFs, including malingering or other "functional" forms of VF loss.     

Multifocal VEP and OCT findings in patients with primary open angle glaucoma: A cross-sectional study

ABSTRACT: Bakground To evaluate objectively the anatomical and functional changes of optic nerve in eyes with primary open angle glaucoma (POAG) by the joint use of optical coherence tomography (OCT) and multifocal visual evoked potentials (mfVEP). METHODS: 29 eyes with open angle glaucoma and visual field defects, as well as 20 eyes of 10 age-matched control normal subjects were tested. All participants underwent a complete ophthalmological examination. Moreover, Humphrey visual field test, OCT examination and recording of mfVEP were performed. Amplitude and implicit time of mfVEP, as well as RNFL thickness were measured. Differences in density components of mfVEP and in RNFL thickness among POAG eyes and control eyes were examined using Student's t-test. RESULTS: In glaucomatous eyes the mean Retinal Response Density (RRD) was lower than normal in ring 1, 2 and 3 of mfVEP (p < 0.0001). Specifically the mean amplitude of mfVEP in POAG eyes was estimated at 34.2 +/- 17.6 nV/deg2, 6.9 +/- 4.8 nV/deg2 and 2.6 +/- 1.6 nV/deg2 in rings 1, 2 and 3 respectively. In contrast the mean implicit time was similar to control eyes. In addition, the mean RNFL thickness in POAG eyes was estimated at 76.8 +/- 26.6 mum in the superior area, 52.1 +/- 16.3 mum in the temporal area, 75.9 +/- 32.5 mum in the inferior area and 58.6 +/- 19.4 mum in the nasal area. There was a statistically significant difference in RNFL thickness in all peripapillary areas (p < 0.0001) between POAG eyes and controls, with superior and inferior area to present the highest decrease. CONCLUSIONS: Our study shows that, although Standard Automatic Perimetry is the gold standard to evaluate glaucomatous neuropathy, the joint use of mfVEP and OCT could be useful in better monitoring glaucoma progression.     

Multifocal VEP (mfVEP) reveals abnormal neuronal delays in diabetes

This pilot study examined the diagnostic role of multifocal visually evoked potentials (mfVEP) in a small number of patients with diabetes. mfVEP, mfERG, and fundus photographs of both eyes of five patients with diabetes, three with nonproliferative diabetic retinopathy (NPDR) and two without NPDR were examined. Thirteen control subjects were also examined. Eighteen zones were constructed from the 60-element mfVEP stimulus array. mfVEP implicit time (IT) and amplitude (SNR) differences were tested between subject groups. We also examined whether there was a difference in function for patches with and without retinopathy in the NPDR group. Lastly, we compared mfVEP and mfERG results in the same patients. We found significant mfVEP IT differences between controls and all patients with diabetes, controls and diabetics without retinopathy, and between controls and diabetics with retinopathy. The subject groups did not differ significantly in terms of SNR. In the retinopathy group, ITs from zones with retinopathy were significantly longer than ITs from zones without retinopathy (P = 0.016). mfERG IT was more frequently abnormal than mfVEP IT. In addition, mfERG hexagons were twice as likely to be abnormal if the corresponding mfVEP zone was abnormal (P < 0.05). mfVEP implicit times are significantly delayed in patients with diabetes even when there is no retinopathy. These cortical response results are similar, albeit considerably less abnormal, than those previously reported for retinal (mfERG) responses in patients with diabetes. A correlation exists between the location of abnormal mfERG hexagons and abnormal mfVEP zones.     

Comparing multifocal VEP and standard automated perimetry in high-risk ocular hypertension and early glaucoma

PURPOSE: To compare the diagnostic performance of multifocal visual evoked potential (mfVEP) and standard automated perimetry (SAP), in eyes with high-risk ocular hypertension or early glaucoma. METHODS: Both eyes of 185 individuals with high-risk ocular hypertension or early glaucoma were evaluated. Subjects ranged in age from 37 to 87 (mean +/- SD: 61 +/- 11 years). Pattern-reversal mfVEPs were obtained by using VERIS (Electro-Diagnostic Imaging, San Mateo, CA) with a four-electrode array and were analyzed with custom software. SAP visual fields (SITA-standard; Carl Zeiss Meditec, Inc., Dublin, CA) were obtained within 22.3 +/- 27.0 days of the mfVEP. Stereo disc photographs and Heidelberg Retina Tomograph (HRT) images were obtained during one visit, which was within 24.8 +/- 50.4 days of the mfVEP and 33.1 +/- 62.9 days of the SAP visual field. Abnormalities on the mfVEP were defined by using a variety of cluster criteria: SAP with pattern standard deviation (PSD) P 相似文献   

Multifocal Visual Evoked Responses to Dichoptic Stimulation Using Virtual Reality Goggles: Multifocal VER to Dichoptic Stimulation

Multifocal visual evoked potentials (mfVEPs) have demonstrated good diagnostic capabilities in glaucoma and optic neuritis. This study aimed at evaluating the possibility of simultaneously recording mfVEP for both eyes with dichoptic stimulation using virtual reality goggles and also to determine the stimulus characteristics that yield maximum amplitude. ten healthy volunteers were recruited and temporally sparse pattern pulse stimuli were presented dichoptically using virtual reality goggles. Experiment 1 involved recording responses to dichoptically presented checkerboard stimuli and also confirming true topographic representation by switching off specific segments. Experiment 2 involved monocular stimulation and comparison of amplitude with Experiment 1. In Experiment 3, orthogonally oriented gratings were dichoptically presented. Experiment 4 involved dichoptic presentation of checkerboard stimuli at different levels of sparseness (5.0 times/s, 2.5 times/s, 1.66 times/s and 1.25 times/s), where stimulation of corresponding segments of two eyes were separated by 16.7, 66.7,116.7 & 166.7 ms respectively. Experiment 1 demonstrated good traces in all regions and confirmed topographic representation. However, there was suppression of amplitude of responses to dichoptic stimulation by 17.9±5.4% compared to monocular stimulation. Experiment 3 demonstrated similar suppression between orthogonal and checkerboard stimuli (p = 0.08). Experiment 4 demonstrated maximum amplitude and least suppression (4.8%) with stimulation at 1.25 times/s with 166.7 ms separation between eyes. It is possible to record mfVEP for both eyes during dichoptic stimulation using virtual reality goggles, which present binocular simultaneous patterns driven by independent sequences. Interocular suppression can be almost eliminated by using a temporally sparse stimulus of 1.25 times/s with a separation of 166.7 ms between stimulation of corresponding segments of the two eyes.