Multifocal electroretinograms in X-linked retinoschisis

PURPOSE: To study local retinal cone function in patients with X-linked retinoschisis (XLRS) by multifocal ERGs (mfERGs). METHODS: mfERGs were recorded from seven eyes of seven patients with XLRS (mean age +/- SD, 22.1 +/- 3.2 years; range, 18 to 25 years). Five eyes had microcystic changes in the macula and two eyes had nonspecific macular degeneration. Two eyes had peripheral retinoschisis, and some of the stimuli fell on this area. The stimulus array consisted of 103 hexagons and the total recording time was set at approximately 4 minutes. The amplitudes and implicit times of both focal and summed responses for the first- and second-order kernels were analyzed. RESULTS: The amplitudes of the first-order kernel were markedly reduced in the central retina in all eyes. A large variation was observed in the amplitudes outside the fovea. The amplitudes of the focal cone ERGs at the peripheral retinoschisis did not differ from those recorded from adjacent retinal loci without the retinoschisis. The implicit times of the first-order kernel were significantly delayed, and the amplitudes of the second-order kernels were more affected than the first-order kernels across the whole field in all XLRS eyes. CONCLUSIONS: The cone-mediated retinal responses were more impaired in the central than peripheral retina in eyes with XLRS. Delayed implicit times of the first-order kernel and reduced second-order kernel across the whole testing field in all XLRS eyes suggest that there is widespread cone-system dysfunction in XLRS.     

Multifocal electroretinogram delays predict sites of subsequent diabetic retinopathy

PURPOSE: To examine the potential of abnormal mfERGs to predict the development of diabetic retinopathy at corresponding retinal locations 1 year later. METHODS: One eye of 11 diabetic patients with nonproliferative diabetic retinopathy (NPDR) and 11 diabetic patients without retinopathy were retested 12 months after initial testing. At each time, mfERGs were recorded from 103 retinal locations, and fundus photographs were taken within 1 month of each recording. Local mfERG implicit times were measured and their z-scores were calculated based on results obtained from 20 age-matched control subjects. mfERG abnormalities were defined as z-scores of 2 or more for implicit time and z-scores of -2 or less for amplitude (P < or = 0.023). mfERG z-scores were mapped onto fundus photographs, and the relationship between baseline abnormal z-scores and new retinopathy at follow-up was examined. RESULTS: New retinopathy developed in 7 of the eyes with NPDR after 1 year. In these eyes, 70% of the mfERGs in areas of new retinopathy had abnormal implicit times at baseline. In contrast, only 24% of the responses in regions that remained retinopathy free were abnormal at baseline. Relative risk of development of new retinopathy over 1 year in the areas with abnormal baseline mfERG implicit times was approximately 21 times greater than that in the areas with normal baseline mfERGs (odds ratio = 31.4; P < 0.001). Eyes without initial retinopathy did not develop new retinopathy within the study period, although 4 of these 11 eyes had abnormal implicit times at baseline. mfERG implicit times tended to be more delayed at follow-up than at baseline in NPDR eyes, but not in eyes without retinopathy and control eyes. mfERG amplitudes had no predictive power. CONCLUSIONS: Localized functional abnormalities of the retina reflected by mfERG delays often precede the onset of new structural signs of diabetic retinopathy. Those functional abnormalities predict the local sites of new retinopathy observed 1 year later.     

Multifocal ERG findings in complete type congenital stationary night blindness

PURPOSE. To study the multifocal electroretinogram (mfERG) in patients with the complete type of congenital stationary night blindness (cCSNB), which is thought to be due to a defect in neurotransmission from the photoreceptors to the ON-bipolar cells. METHODS. mfERGs were recorded with the VERIS recording system from four patients with cCSNB, none of whom had nystagmus. The stimulus array consisted of 61 hexagons, and the total recording time was approximately 4 minutes. The amplitudes and implicit times of the first- and second-order kernels of the local responses were compared with those from 20 myopic controls. Waveforms of the summed response from all locations were also compared between the two groups. RESULTS. The first-order kernels of the mfERGs of cCSNB patients had normal amplitudes but delayed implicit times for nearly the whole field tested. The second-order kernel was severely attenuated in amplitude in cCSNB patients. The ratios of the second- to first-order kernel amplitudes were significantly reduced in cCSNB and clearly separated the cCSNB group from the control group without any overlap of the values. CONCLUSIONS. The second-order kernel, which is involved in adaptative mechanism of the retina to repeated flashes, is selectively reduced in cCSNB. The delay of the implicit times of the first-order kernel in patients with cCSNB may be related to the severe amplitude reduction of the second-order kernel.     

First and second-order kernel multifocal electroretinography abnormalities in acute central serous chorioretinopathy

Purpose To evaluate the first and second-order kernel multifocal electroretinogram (mfERG) response abnormalities in patients with acute central serous chorioretinopathy (CSC). Methods This was a cross-sectional observational study in which 45 eyes of 45 patients with acute CSC underwent mfERG recordings. Peak amplitudes and implicit times of the first and second-order kernel responses were analyzed and compared with 20 age-matched normal controls. Correlation analyses were performed between the patients’ visual acuity and the first and second-order amplitudes and implicit times. Results The first-order N1 and P1 mfERG amplitudes in the central three concentric rings were reduced in eyes with acute CSC compared with controls (P < 0.05). The first-order P1 implicit times of the central four rings were also delayed (P < 0.05). For the second-order mfERG response, there were significant reductions in the second-order P1 and N1 amplitudes in rings 3–5 compared with controls (P < 0.05). No significant difference between the second-order P1 and N1 implicit times was found compared with controls (P > 0.05). Correlation analyses showed significant correlations between visual acuity and the first-order N1 response amplitudes of rings 1 and 2, and for the first-order N1 and P1 implicit times of rings 1–4 (P < 0.05). Conclusion Both first and second-order mfERG response abnormalities occur in eyes with acute CSC. These results suggest that in acute CSC, while outer retinal dysfunction is mostly localized to the central macula, there might be more widespread impairment in adaptive mechanisms of the inner retina or outer plexiform layer dysfunction in the more peripheral macula. Presented in part in the 44th annual symposium of the International Society of Clinical Electrophysiology of Vision (ISCEV), Fontevraud, France, June 2006.     

Towards optimal filtering of "standard" multifocal electroretinogram (mfERG) recordings: findings in normal and diabetic subjects

AIMS: To study the effects of two commonly used pre-amplifier filtering bandwidths on normal multifocal electroretinogram (mfERG) responses and their comparative abilities to detect retinal disease. METHODS: 103 standard mfERGs were recorded simultaneously in two channels with different pre-amplifier settings (10-100 Hz and 10-300 Hz) from one eye of each of 20 normal subjects, 17 diabetics with non-proliferative diabetic retinopathy (NPDR), and 12 diabetics without retinopathy. Signal to noise ratios (SNR) of the normal subjects' first order mfERGs were compared between channels. All subjects' amplitudes and implicit times were derived using a "template stretching" method. For comparison, implicit time was also measured using a "template sliding" method. mfERG amplitudes and implicit times were compared between the channels and among subject groups. RESULTS: Normal mean amplitudes and implicit times were similar for the two channels. However, normal 10-100 Hz recordings had significantly higher SNR and lower intersubject variability than 10-300 Hz recordings. In NPDR, the 10-100 Hz channel identified significantly more implicit time and amplitude abnormalities. In the diabetics without retinopathy, 10-100 Hz filtering identified significantly more implicit time abnormalities than 10-300 Hz filtering. For both filter settings, diabetic implicit times were more often abnormal than amplitudes. The 10-100 Hz channel was superior for both implicit time measurements. CONCLUSION: Standard mfERGs recorded from normal eyes and filtered 10-100 Hz contain less noise, higher SNR, and less intersubject variability than those filtered at 10-300 Hz. This underlies the finding that the 10-100 Hz filter setting identifies more retinal dysfunction than the 10-300 Hz setting.     

Multifocal electroretinogram in children on atropine treatment for myopia

AIM: To assess retinal function by multifocal electroretinogram (mfERG) in children on atropine eye drops for the treatment of myopia. METHODS: mfERGs were recorded in children receiving atropine eye drops (n = 48) once daily for 2 years and in those receiving placebo eye drops (n = 57) for a similar time. All recordings were performed between the second and third month of cessation of atropine/placebo treatment by a masked investigator. The amplitude and implicit time of the first order kernel (k1) and first slice of the second order kernel (k21) of mfERG responses were used to study the outer and inner retinal function, respectively. RESULTS: There was no significant reduction in k1 response amplitudes of the atropine group compared to that of the placebo group (N1, p = 0.181; P1, p = 0.150). No significant difference in the k1 response implicit times between the groups was found (N1, p = 0.767; P1, p = 0.849). The differences in the k21 amplitudes and implicit times between the groups were not statistically significant (k21 amplitude, p = 0.058; k21 implicit time, p = 0.156). CONCLUSIONS: Daily atropine usage over 2 years for the treatment of myopia has no significant effect on retinal function as demonstrated by recordings of mfERG.     

多焦视网膜电图在原发性开角型青光眼诊断中的应用

目的：探讨多焦视网膜电图（mfERG）技术用于诊断原发性开角型青光眼（POAG）的准确性及实效性。方法：系列病例研究。于2014 年10 月至2016 年3 月在云南省第一人民医院门诊就诊并确诊的POAG患者中随机选取60例（86眼）作为青光眼组,其中早、中、晚期组分别为20例（27眼）、20例（29眼）、20 例（30 眼）。同时随机选取同期健康体检者60 例（120 眼）作为对照组。各组研究对象分别通过mfERG进行技术诊断,观察比较mfERG二阶反应各环与各象限的P1 波反应密度值及潜伏期。组间数据比较采用单因素方差分析和 χ2检验。结果：与对照组相比,早期青光眼组1～5环的P1波反应密度值无明显变化,差异无统计学意义,但颞下、颞上象限P1波反应密度值下降明显,差异有统计学意义（P < 0.05）。中期青光眼组2～5环及4个象限P1波反应密度值较对照组下降明显,差异均有统计学意义（P < 0.05）。晚期青光眼组1～5环及4个象限P1波反应密度值较对照组明显下降,差异均有统计学意义（P < 0.05）。早、中、晚期青光眼组1～5环及4个象限P1波的潜伏期均较对照组延长,差异均有统计学意义（P < 0.05）。各期青光眼组中,晚期青光眼组较早期青光眼组潜伏期延长更明显,差异有统计学意义（P < 0.05）。结论：mfERG 1～5 环P1波潜伏期和密度值的变化可在一定程度上反映青光眼视网膜的损害程度,对诊断早期POAG有一定的临床价值。     

Retinal disorders in northern Brazilian patients treated with chloroquine assessed by multifocal ERG

The effects of chloroquine intake on the retinal function in a Brazilian population of patients were assessed by multifocal electroretinography. Twenty-four randomly chosen eyes of patients treated with chloroquine for rheumatoid arthritis and systemic lupus erythematosus were examined using multifocal electroretinography (mfERG). Control measurements were acquired from 21 randomly chosen eyes of age-matched healthy subjects. None of the study participants had an inherited retinal disease or a Snellen visual acuity reduced to less than 20/40. In patients and control subjects, cumulative chloroquine dose, total daily dose, duration of treatment, retinal examination, visual field defects, visual acuity, and the mfERG were assessed. The average amplitudes and implicit times of the N1, P1, and P2 components of the mfERGs were measured in the central hexagon (R1) and in five rings (R2–R6). The values measured in patients and normal subjects were compared. The P1 amplitudes in R2 were significantly decreased in the patients. In addition, the amplitudes of N1 and N2 in R1 were significantly smaller in the patients. The implicit times of none of the components were significantly different between patients and controls. The response amplitude was not significantly correlated with cumulative dose and duration of intake. There was no correlation with retinal appearance, visual field, and visual acuity. In agreement with earlier data, the central mfERG amplitudes were decreased in chloroquine patients indicating functional alterations in the retina. These changes are also present in a Brazilian population suggesting that the effects of chloroquine are general and that genetic background and life circumstances probably have, if at all, only little effect.     

Follow up in open angle glaucoma. A comparison of static perimetry and the fast stimulation mfERG

PURPOSE: To compare changes in the mfERG to visual field changes observed in OAG. METHODS: Twenty-nine eyes with OAG were included. Visual fields (Octopus d32) and mfERGs (VERIS) were obtained at a mean interval of 9 months (SD 6 months). MfERG recording parameters were as follows: 103 hexagons stimulated the central 50 degrees. M-sequence 2--5, stimulus base interval 13.33 ms, Lmax 200 cd/m2, contrast 99%. First (KI) and second (KII) order response components were analyzed for the individual quadrants of the visual field and compared to the corresponding mean deviation (MD) of the static perimetry. RESULTS: Changes in visual field parameters and changes in the mfERG did not differ significantly. Overall, as mean deviation increased there was a tendency for implicit times to increase and for amplitudes to decrease. However, over the follow up interval of 9 months only minor changes were observed. The second order response component correlated best with changes in MD (p < 0.05). These were the correlation between MD and KII N1 (r: 0.36) in the upper temporal field, between MD and KII N2 (r: 0.40) in the upper nasal field and between MD and KII P1 (r: 0.38) in the lower temporal field. When a subgroup of 10 eyes that had been tested at least 3 times over 16.8 months (SD 5.5) was examined there were still only minor changes observed in either parameter. CONCLUSION: While the changes over time in the mfERG and the visual field showed a reasonable correlation, changes observed in either parameter were extremely small over the time period observed, thus requiring a longer follow up and/or a more sensitive stimulation technique.     

LED刺激器多焦视网膜电图一阶和二阶反应波形研究

目的研究二极管发光器(LED)的多焦视网膜电图(mfERG)的一阶及二阶波形特点。设计前瞻性、非对照干预研究。研究对象18例(18眼)正常人。方法18眼随机分为两组分别作阴极射线管(CRT)及LED的mfERG检查。LED刺激时间分为1/10(1．7ms)、3/10(5ms)、5/10(8．3ms)、7/10(11．7ms)、10/10(16．7ms)5种。主要指标mfERG总和反应波形特点,P1、N1及N2波形态、振幅密度及潜伏期。结果CRT及LED刺激器mfERG一阶反应波形基本相似；CRT及LED刺激器的mfERG二阶反应波形不同,前者的P1波呈尖峰状,后者的P1波较宽,呈方形,且伴有一个较深的N2波。随着刺激时间的延长,LED刺激器的mfERG一阶及二阶反应中的P1波及N1波的振幅密度增加,潜伏期延长。结论CRT及LED刺激器的mfERG一阶反应波形基本相同,但LED的二阶反应波形更丰富,其可能包涵了更多视网膜内层信息。(眼科,2006,15：351-355)     

Abnormal multifocal ERG findings in patients with normal-appearing retinal anatomy

To evaluate eyes with abnormal visual fields and multifocal electroretinograms (mfERGs) but normal-appearing frequency-domain optical coherence tomography (fdOCT) scans, the thicknesses of the outer retinal layers were measured. A total of 25 eyes from 17 patients, including 15 eyes previously tested (Dale et al. in Doc Ophthalmol 120(2):175–186, 2009) were examined. All patients were evaluated with standard automated perimetry (SAP) using the 24-2 and/or 10-2 program (Zeiss Meditec), mfERG with 103 hexagons (Veris, EDI), and fdOCT imaging (3DOCT-2000, Topcon) with scans of the macula. All patients had reliable visual fields showing macular defects and good quality mfERG and fdOCT results. The mfERG results were classified as abnormal based on decreased amplitudes and/or increased latencies corresponding to the abnormal visual field. Based on visual inspection, three experienced observers classified the fdOCT scans as normal or inconclusive, as opposed to clearly abnormal. Retinal layers of the fdOCT scans were manually segmented with the aid of a computer program and compared to mean thicknesses from 20 controls. The thicknesses of the outer segment plus retinal pigment epithelium, total receptor, and inner nuclear layers were measured. Quantitative analysis of fdOCT scans demonstrated thinning of the outer retina in some scans that was not readily apparent on visual inspection. One or more of the outer retinal layers was significantly thinner in 15 of the 25 eyes. The absence of significant thinning in the other 10 eyes represents instances in which functional loss measured by visual fields and mfERGs can precede clear structural changes on fdOCT.     

Assessment of central retinal function in patients with advanced retinitis pigmentosa

PURPOSE: To assess central retinal function in patients with advanced retinitis pigmentosa (RP) using the multifocal (mf)ERG and static perimetry. METHODS: Patients with RP; a nonrecordable, full-field (ff)ERG; and visual acuity (VA) of 相似文献   

Atypical multifocal ERG responses in patients with diseases affecting the photoreceptors

The purpose of this study was to investigate atypical multifocal ERG (mfERG) responses for patients with diseases that can affect the photoreceptors. MfERGS were obtained from seven patients with retinitis pigmentosa (RP), three with progressive cone dystrophy (CD) and eight with diabetic retinopathy (DR). Both first- and second-order kernel responses were analyzed. The amplitudes and implicit times of the first-order responses were compared to those obtained from age-similar controls. For the first slice of the second-order response, the root-mean-square (RMS) and the signal-to-noise ratio (SNR) of each response were calculated. Achromatic visual fields were also obtained from each subject. For the three groups of patients, first-order responses with relatively large amplitudes, broad-shaped waveforms and markedly increased implicit times had non-measurable second-order responses. These responses were associated with areas of decreased visual field sensitivity. As RP, CD and DR affect the outer retina, the results are consistent with damage to the outer plexiform layer rather than damage to the inner retina.     

Changes in the s-Wave of Multifocal Electroretinograms in Eyes with Primary Open-Angle Glaucoma

Purpose To determine whether the s-wave is present in the multifocal electroretinogram (mfERG) and whether it is altered in eyes with primary open-angle glaucoma (POAG).Methods A Visual Evoked Response Imaging System was used to record mfERGs from 15 eyes of 15 normal adults, as control eyes, and from 15 eyes of 15 patients with POAG. The stimulus consisted of 37 hexagonal stimulating elements with luminances of 200cd/m² (white), 66.6cd/m² (gray), and 4cd/m² (black). The white or black element was presented at five different base periods (bpds) from 13.3 to 213.3ms according to a binary m-sequence. In the intervals between the white and black (or white) elements, gray elements were inserted at 75Hz. The changes in the amplitude and implicit time of the s-wave of the all-trace waveform of the first-order kernel of the mfERG were compared with the mean deviation (MD) of retinal sensitivity in the whole visual field measured with a Humphrey Field Analyzer.Results The s-wave was present as a positive wavelet on the descending limb of the first-order kernel response of the mfERGs of all eyes with POAG. The s-wave amplitude increased with prolongation of the bpd, as occurs in normal eyes. The mean amplitudes of the s-waves at bpds of 53.3 and 106.7ms were significantly smaller in the eyes with POAG than in the control eyes. The correlation between the s-wave amplitude and the severity of disturbance in the entire visual field indicated by the MD was not significant in eyes with POAG.Conclusions The characteristics of the s-wave in glaucomatous eyes were the same as those in the control eyes, but the amplitude of the s-waves in POAG eyes was significantly lower than that in the control eyes. This suggests that ganglion cells may be involved in the development of the s-wave. When comparing the s-wave with static perimetry, more local responses of the s-wave and more local retinal sensitivity in the static perimetry will be appropriate. Jpn J Ophthalmol 2004;48:208–214 © Japanese Ophthalmological Society 2004     

Multifocal Electroretinography (mfERG) in Insulin Dependent Diabetics with and without Clinically Apparent Retinopathy

Purpose: To study the retinal function, using multifocal electroretinography (mfERG), in diabetic patients with mild and moderate retinopathy, and in diabetics without clinically apparent retinopathy. Methods: Thirty-one patients with insulin dependent diabetes mellitus, eleven without any clinically apparent retinopathy, twelve with mild retinopathy and eight with moderate retinopathy, were studied. Ophthalmologic examination included testing of visual acuity, fundus inspection, fundus photography and mfERG. Sixteen subjects without eye disease and with normal visual acuity were used as controls for comparison of mfERG results. Results: The patients had a mean diabetes duration of 23±9 years. All patients and controls had a visual acuity of 1.0. In the first order component of the mfERG there were significantly higher ring amplitudes in the diabetics compared to the controls (p=0.001). In the second-order component of the mfERG, there was a significantly prolonged implicit time in the diabetics who had retinopathy compared to those without any retinopathy (p=0.026). The third positive waveform in the ring amplitudes of the second-order component, were absent in 15/31 of patients with diabetes, but were easily distinguished in all the controls; p<0.001. This waveform was absent in 6/11 patients without retinopathy. Conclusion: Patients with insulin dependent diabetes have specific abnormalities in both the first and the second-order component of the mfERG. These abnormalities reflect both vascular changes in the retina and, probably simultaneously, pathology in inner retinal function, also in the diabetics without clinically apparent retinopathy.     

Multifocal electroretinography and fluorescein angiography in retinal vein occlusion

PURPOSE: To interpret the responses of multifocal electroretinography (mfERG) of the central macula in retinal vein occlusion and correlate them with findings of fluorescein angiography, optical coherence tomography (OCT), and visual acuity. METHODS: In a prospective observational case series, 25 patients with branch or hemiretinal vein occlusion were examined by means of mfERG, fluorescein angiography, OCT, and visual acuity. RESULTS: In eyes with macular ischemia shown by fluorescein angiography, the implicit time was significantly longer than that in eyes without macular ischemia (P = 0.006; Mann-Whitney test). The amplitudes in the first-order kernel responses in the ischemic eyes were more reduced (P = 0.04; Mann-Whitney test), and the amplitudes in the central macula correlated well with visual acuity (P = 0.006; Pearson correlation). There was no significant correlation between the degree of retinal thickening as measured by OCT and the mfERG responses, although there was a trend toward reduced amplitudes in the maculae with central retinal thickening (P = 0.08; Pearson correlation). CONCLUSION: Macular ischemia as measured by fluorescein angiography correlates well with the prolonged implicit time on the first-order kernel response in mfERG, but no significant correlation was detected between the responses of mfERG and the OCT findings. Further investigations will demonstrate if this can be used as a prognostic instrument in the selection of patients, who will most likely benefit from future treatments.     

mfERG二阶Kernel反应对开角型青光眼的诊断价值

目的　观察并评估多焦视网膜电图(mfERG)二阶Kernel反应(SOK)在原发性开角型青光眼 (POAG)中的诊断价值。 方法　POAG患者 45例(78眼),分为早期、进展期、晚期。正常对照 24例 (48眼 )。对所有对象行mfERG检查,记录各环、象限的SOK的P1波反应密度和潜伏期,进行统计分析。 结果　正常对照随着离心率的增加, 5个环的SOK的P1波反应密度明显下降,潜伏期无明显变化; 4个象限的SOK的P1波反应密度及潜伏期无明显变化。POAG早期1环、2环及 4个象限SOK的P1波反应密度均比正常对照降低;进展期和晚期各环和各象限的SOK的P1波反应密度均比正常对照组降低;POAG各期之间的各环及各象限的SOK的P1波反应密度的差异具有显著性意义,潜伏期的差异均无显著性意义;POAG各期的各环及各象限的SOK的P1波潜伏期与正常对照相比差异均无显著性意义。SOK在POAG早期、进展期、晚期的敏感性依次为 74 19%、88 00%、100 00%,差异具有显著性意义。总体敏感性为 85 90%,特异性为 79 17%。 结论　mfERG的SOK的P1波反应密度可以较敏感地检测出POAG各期视功能的损害,对POAG的诊断尤其是早期诊断具有重要的临床意义。     

A new wavelet in the multifocal electroretinogram, probably originating from ganglion cells

PURPOSE: To report the properties of a newly detected positive wavelet on the descending limb of P1 of the first-order kernel of the human multifocal electroretinogram (mfERG). METHODS: Twenty eyes of 20 normal individuals, ages 21 to 29 years (mean, 25.6) and nine eyes of 6 patients with optic neuritis ages 5 to 38 years (mean, 17.3) were studied. mfERGs were recorded with a visual evoked response imaging system with the number of stimulus elements set at 37. The stimulus frequency was changed from 75 to 37, 18, 9.4, 4.7, and 2.3 Hz, and the contrast of the stimuli was lowered to 50%. RESULTS: In normal eyes, a positive wavelet appeared on the descending limb of P1 of the first-order kernel of the mfERG when the stimulus frequency was reduced from 75 to 18 Hz. The wavelet had a mean amplitude of 4.2 nV/deg(2) and a mean implicit time of 34 ms at 18 Hz. When the stimulus frequency was reduced further to 2.3 Hz, the amplitude of the wavelet increased significantly (P < 0.05) compared with that at 18 Hz. The amplitudes of the wavelet elicited from the nasal side of the retina were significantly larger (P < 0.05) than those from the temporal side and decreased significantly (P < 0.05) with increasing distance from the optic disc. The wavelet was not present in any of the patients with newly diagnosed optic neuritis, but reappeared with recovery from the disease. The recovery of the wavelet correlated significantly with the recovery of visual acuity and of central critical fusion frequency. CONCLUSIONS: The amplitude of the wavelet on the descending limb of P1 of the first-order kernel of the mfERG was dependent on the stimulus frequency and the retinal locus. The wavelet was not present in the mfERGs recorded in patients with optic neuritis, but returned with recovery from the disease. These findings suggest that the neural activity of the ganglion cells give rise to this wavelet.     

多焦视网膜电图在Vogt一小柳原田病急性期及恢复期随访中的应用

背景应用多焦视网膜电图（mfERG）评价急性期Vogt—Koyanagi-Harada（VKH）病的视网膜功能已有研究和报道,但VKH病恢复期mfERG如何变化文献报道不多。目的观察及随访VKH病急性期与恢复期视力及mfERG的变化特点。方法为回顾性临床对照研究设计,纳入在中山大学中山眼科中心确诊为VKH病急性期患者18例35眼,对患者的视力、mfERG及荧光素眼底血管造影（FFA）检查,并对VKH恢复期患者随访18个月,重复上述检查4次,对正常人、VKH急性期和恢复期患者的mfERG结果进行比较。结果本组急性期VKH病患者视力在0．01～1．0之间,仅1眼（2．86％）视力为1．0,91．4％（32／35眼）视力〈0．6,较正常对照组视力下降,差异有统计学意义（P〈0．01）。正常对照组、VKH急性期组和恢复期组患者mfERG1～6环的N1、P1波反应密度的总体差异比较均有统计学意义（P〈0．05）;与正常对照组比较,VKH急性期组和恢复期组患者mfERG1—6环的N1、P1波反应密度均明显降低,差异有统计学意义（P〈0．05）,但各环振幅降低的幅度不同,以1～3环降低最为严重,1环P1波振幅仅有正常对照的22％,随离心度增加,振幅降低逐渐减轻。与VKH急性期组相比较,恢复期组（2个月）患者视力为0．1～1．2之间,50％视力≥1．0,mfERGN1、P1波反应密度的提高以1～2环显著,与急性期相比差异均有统计学意义（P〈0．05）;但各环mfERGN1、P1波反应密度仍与正常有很大差异,总体仅及正常振幅的44％。VKH恢复期患者4次随访结果显示,患眼各期视力稳定,mfERG各波振幅有轻度下降趋势,但差异无统计学意义（P〉0．05）;3环内N1、P1隐含时缩短,4次随访总体差异有统计学意义（P〈0．05）。结论VKH对患者视力及后极部视网膜功能有严重影响,黄斑区是疾病影响最为严重且治疗前后功能变化较大的部位。治疗后即使视力恢复较理想,但mfERG结果证实视网膜功能仍有较大程度损害。     

Assessing Responses of the Macula in Patients with Macular Holes using a New System Measuring Localized Visual Acuity and the mfERG

Purpose: To evaluate acuity and multifocal electroretinogram (mfERG) responses from the macula in affected and unaffected fellow eyes of patients with macular holes. Methods: We tested 10 eyes with macular hole and 10 fellow eyes from 11 patients. We measured local visual acuity thresholds at 27 discrete locations within 21° diameter using the Functional Fundus Imaging System (FFIS), a psychophysical system that measures visual acuity as a function of visual field location, and local ERG responses within 45° diameter using the mfERG. Results: In the affected eyes, the mean FFIS visual acuity thresholds were significantly elevated within the central 21° diameter area, compared to a group of control eyes. No significant differences were found between the acuities of the fellow eyes compared to those of the control group. The amplitudes of the first positive peak of the mfERG were reduced in the central 7.8° in affected eyes. In the central 2°, 4 out of 10 affected eyes showed non-measurable ERG signals. The remaining six eyes showed significantly reduced mean amplitudes, but not delayed implicit times, when compared to the control group. For the fellow eyes, the mean amplitudes of the mfERG and implicit times did not differ from the means of the control eyes. Conclusions: Both local psychophysical and electrophysiological testing demonstrated retinal dysfunction extending beyond the site of the macular holes in some patients (three of the patients had central mfERG amplitudes falling within the normal range).