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Sarossy M, Crowston J, Kumar D, Weymouth A, Wu Z. Time-Frequency Analysis of ERG With Discrete Wavelet Transform and Matching Pursuits for Glaucoma. Transl Vis Sci Technol 2022; 11:19. [PMID: 36227605 PMCID: PMC9583752 DOI: 10.1167/tvst.11.10.19] [Citation(s) in RCA: 4] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/01/2023] Open
Abstract
Purpose To examine the performance of two time-frequency feature extraction techniques applied to electroretinograms (ERGs) for the prediction of glaucoma severity. Methods ERGs targeting the photopic negative response were obtained in 103 eyes of 55 patients with glaucoma. Features from the ERG recordings were extracted using two time-frequency extraction techniques based on the discrete wavelet transform (DWT) and the matching pursuit (MP) decomposition. Amplitude markers of the time-domain signal were also extracted. Linear and multivariate adaptive regression spline (MARS) models were fitted using combinations of these features to predict estimated retinal ganglion cell counts, a measure of glaucoma disease severity derived from standard automated perimetry and optical coherence tomography imaging. Results Predictive models using features from the time-frequency analyses-using both DWT and MP-combined with amplitude markers outperformed predictive models using the markers alone with linear (P = 0.001) and MARS (P ≤ 0.011) models. For example, the proportions of variance (R2) explained by the MARS model using the DWT and MP features with amplitude markers were 0.53 and 0.63, respectively, compared to 0.34 for the model using the markers alone (P = 0.011 and P = 0.001, respectively). Conclusions Novel time-frequency features extracted from the photopic ERG substantially added to the prediction of glaucoma severity compared to using the time-domain amplitude markers alone. Translational Relevance Substantial information about retinal ganglion cell dysfunction exists in the time-frequency domain of ERGs that could be useful in the management of glaucoma.
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Affiliation(s)
- Marc Sarossy
- Ophthalmology, Department of Surgery, University of Melbourne, Melbourne, Victoria, Australia
| | | | | | - Anne Weymouth
- Department of Optometry and Vision Sciences, University of Melbourne, Melbourne, Victoria, Australia
| | - Zhichao Wu
- Ophthalmology, Department of Surgery, University of Melbourne, Melbourne, Victoria, Australia.,Centre for Eye Research Australia, Royal Victorian Eye and Ear Hospital, East Melbourne, Victoria, Australia
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2
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Awwad MH, Nada O, Hamdi MM, El-Shazly AAEF, Elwan S. Correlation Between Optical Coherence Tomography and Photopic Negative Response of Flash Electroretinography in Ganglion Cell Complex Assessment in Glaucoma Patients. Clin Ophthalmol 2022; 16:893-904. [PMID: 35356699 PMCID: PMC8958198 DOI: 10.2147/opth.s356436] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/30/2021] [Accepted: 03/11/2022] [Indexed: 11/25/2022] Open
Abstract
Purpose To investigate the correlation between the photopic negative response (PhNR) of the light-adapted flash electroretinography (ERG) and measurements of standard automated perimetry (SAP) and optical coherence tomography (OCT) in assessment of retinal ganglion cells’ (RGCs) affection in glaucoma. Patients and Methods A cross-sectional study included 40 eyes of glaucoma patients and 40 eyes of age- and gender-matched normal subjects. Participants underwent a complete ophthalmologic assessment, SAP, OCT, and light-adapted flash ERG using the extended PhNR protocol of the International Society for Clinical Electrophysiology of Vision (ISCEV). Glaucomatous eyes were divided into 3 subgroups: mild (n = 15), moderate (n = 11) and severe glaucoma (n = 14) according to the mean deviation (MD) of SAP. Measurements of SAP, OCT and ERG parameters were analyzed, and correlations between PhNR measurements and other study measurements were evaluated. Results PhNR amplitudes and PhNR/b-wave ratios were significantly reduced in glaucoma cases compared to healthy controls, and they showed a significant and progressive decline across the three glaucoma subgroups (P < 0.05). An exception to this is PT (b-wave peak to PhNR trough) PhNR amplitude where its reduction was statistically non-significant when comparing between controls and mild glaucoma cases (P = 0.178), and between moderate and severe glaucoma cases (P = 0.714). PhNR amplitudes and PhNR/b-wave ratios correlated significantly with SAP and OCT parameters (P < 0.05). Conclusion PhNR correlates well with SAP and OCT parameters in glaucoma assessment. PhNR could be a valuable supplementary tool for objective assessment of the RGCs’ function in glaucoma.
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Affiliation(s)
- Mohammad Hasan Awwad
- Ophthalmology Department, Faculty of Medicine, Ain Shams University, Cairo, Egypt
- Correspondence: Mohammad Hasan Awwad, Misr Lel Tayaran St., New Nozha, Cairo, 11843, Egypt, Tel +201003604524, Email
| | - Ossama Nada
- Ophthalmology Department, Faculty of Medicine, Ain Shams University, Cairo, Egypt
| | - Momen Mahmoud Hamdi
- Ophthalmology Department, Faculty of Medicine, Ain Shams University, Cairo, Egypt
| | | | - Sheriff Elwan
- Ophthalmology Department, Faculty of Medicine, Ain Shams University, Cairo, Egypt
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3
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Sarossy M, Crowston J, Kumar D, Weymouth A, Wu Z. Prediction of glaucoma severity using parameters from the electroretinogram. Sci Rep 2021; 11:23886. [PMID: 34903831 PMCID: PMC8668922 DOI: 10.1038/s41598-021-03421-6] [Citation(s) in RCA: 9] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/04/2021] [Accepted: 11/29/2021] [Indexed: 11/17/2022] Open
Abstract
Glaucoma is an optic neuropathy that results in the progressive loss of retinal ganglion cells (RGCs), which are known to exhibit functional changes prior to cell loss. The electroretinogram (ERG) is a method that enables an objective assessment of retinal function, and the photopic negative response (PhNR) has conventionally been used to provide a measure of RGC function. This study sought to examine if additional parameters from the ERG (amplitudes of the a-, b-, i-wave, as well the trough between the b- and i-wave), a multivariate adaptive regression splines (MARS; a non-linear) model and achromatic stimuli could better predict glaucoma severity in 103 eyes of 55 individuals with glaucoma. Glaucoma severity was determined using standard automated perimetry and optical coherence tomography imaging. ERGs targeting the PhNR were recorded with a chromatic (red-on-blue) and achromatic (white-on-white) stimulus with the same luminance. Linear and MARS models were fitted to predict glaucoma severity using the PhNR only or all ERG markers, derived from chromatic and achromatic stimuli. Use of all ERG markers predicted glaucoma severity significantly better than the PhNR alone (P ≤ 0.02), and the MARS performed better than linear models when using all markers (P = 0.01), but there was no significant difference between the achromatic and chromatic stimulus models. This study shows that there is more information present in the photopic ERG beyond the conventional PhNR measure in characterizing RGC function.
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Affiliation(s)
- Marc Sarossy
- Ophthalmology, Department of Surgery, University of Melbourne, Melbourne, VIC, Australia.
| | | | | | - Anne Weymouth
- Department of Optometry and Vision Sciences, The University of Melbourne, Melbourne, Australia
| | - Zhichao Wu
- Ophthalmology, Department of Surgery, University of Melbourne, Melbourne, VIC, Australia
- Centre for Eye Research Australia, Royal Victorian Eye and Ear Hospital, East Melbourne, Australia
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Ishizuka M, Machida S, Hara Y, Tada A, Ebihara S, Gonmori M, Nishimura T. Significant correlations between focal photopic negative response and focal visual sensitivity and ganglion cell complex thickness in glaucomatous eyes. Jpn J Ophthalmol 2021; 66:41-51. [PMID: 34843022 DOI: 10.1007/s10384-021-00886-w] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/12/2021] [Accepted: 10/22/2021] [Indexed: 11/28/2022]
Abstract
PURPOSE To determine whether there are significant correlations between the focal photopic negative response (PhNR), the focal visual sensitivity and the ganglion cell complex (GCC) thickness in glaucomatous eyes. STUDY DESIGN Single-center observational study. METHODS Fifty-two eyes of 52 patients (71.4 ± 9.42 years) with clinically diagnosed open angle glaucoma were studied. Thirty-six age-matched normal subjects served as controls. The focal PhNR of the focal macular electroretinograms (fmERGs) were elicited by a 15° circular, a superior semicircular or an inferior semicircular stimulus centered on the fovea. The thickness of the GCC was measured in the corresponding retinal areas in the spectral-domain optical coherence tomographic images. The visual sensitivities (dB) were measured by microperimetry at the retinal area where the fmERGs were elicited and were converted to liner values (1/Lambert). RESULTS The focal PhNR amplitudes were significantly correlated with the visual sensitivities of the full-circle (R = 0.532), the superior (R = 0.530) and inferior (R = 0.526) semicircular responses (P < 0.0001). The GCC thickness was correlated with the visual sensitivities in the same areas with stronger correlations (R = 0.700, 0.759 and 0.650, respectively; P < 0.0001). The focal PhNR amplitudes were proportionally reduced with the thinning of the GCC thickness (R = 0.494, 0.518 and 0.511, respectively; P < 0.0001). CONCLUSIONS The significant correlations between the focal PhNR amplitudes, the focal visual sensitivities and the GCC thickness indicate that these may be good biomarkers to track the changes in the physiology and anatomy of the macular area in glaucomatous eyes.
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Affiliation(s)
- Masahiko Ishizuka
- Department of Ophthalmology, Dokkyo Medical University Saitama Medical Center, 2-1-50 Minami-Koshigaya Koshigaya, Saitama, 343-8555, Japan
| | - Shigeki Machida
- Department of Ophthalmology, Dokkyo Medical University Saitama Medical Center, 2-1-50 Minami-Koshigaya Koshigaya, Saitama, 343-8555, Japan.
| | - Yuji Hara
- Department of Ophthalmology, Dokkyo Medical University Saitama Medical Center, 2-1-50 Minami-Koshigaya Koshigaya, Saitama, 343-8555, Japan
| | - Atsushi Tada
- Department of Ophthalmology, Dokkyo Medical University Saitama Medical Center, 2-1-50 Minami-Koshigaya Koshigaya, Saitama, 343-8555, Japan
| | - Satoshi Ebihara
- Department of Ophthalmology, Dokkyo Medical University Saitama Medical Center, 2-1-50 Minami-Koshigaya Koshigaya, Saitama, 343-8555, Japan
| | - Mana Gonmori
- Department of Ophthalmology, Dokkyo Medical University Saitama Medical Center, 2-1-50 Minami-Koshigaya Koshigaya, Saitama, 343-8555, Japan
| | - Tomoharu Nishimura
- Department of Ophthalmology, Dokkyo Medical University Saitama Medical Center, 2-1-50 Minami-Koshigaya Koshigaya, Saitama, 343-8555, Japan
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Abstract
PRéCIS:: Four parameters of the noninvasive, portable RETeval electroretinogram (ERG) system were found to correlate with visual field mean deviation and optical coherence tomography (OCT) thickness parameters, and may therefore be suitable for glaucoma detection. PURPOSE To investigate the RETeval full-field ERG parameters for accuracy of separating glaucoma and normal eyes, and correlation with glaucoma severity. PATIENTS AND METHODS Sixty-two eyes of 62 primary open-angle glaucoma patients [visual field mean deviation (MD) range: -0.44 to -31.15 dB] and 39 eyes of 39 healthy controls underwent one RETeval test (photopic negative response protocol), OCT imaging, and Humphrey 30-2 visual field testing. The glaucoma patients were divided into early (MD≥-6dB, n=33) and moderate-to-advanced (MD<-6 dB, n=29) groups. RESULTS Significant correlations were found between the best-performing 4 RETeval ERG parameters and the glaucoma severity measures (MD and OCT thickness parameters) for all eyes, all glaucoma eyes and the moderate-to-advanced glaucoma eyes [photopic negative response amplitude at 72 ms (PhNR 72) and MD: r=-0.333, -0.414, and -0.485, respectively, P≤0.008; PhNR 72 and average circumpapillary retinal nerve fiber layer thickness; r=-0.429, -0.450, and -0.542, respectively, P≤0.002]. Except for P-ratio, there was no significant difference between the area under the receiver-operating characteristic (AUROC) values of the OCT thickness parameters (range: 0.927 to 0.938) and the 4 best-performing RETeval ERG parameters (range: 0.839 to 0.905) in the early glaucoma versus control separation. For differentiating the control and the moderate-to-advanced glaucoma eyes, the AUROC values of the 4 best-performing RETeval ERG parameters ranged between 0.924 and 0.958, and no significant difference was found between them and those of the OCT parameters. CONCLUSIONS The noninvasive, portable RETeval full-field ERG device may be useful to detect glaucoma in moderate-to-advanced stages.
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Berezovsky A, Karanjia R, Fernandes AG, Botelho GIS, Bueno TLN, Ferraz NN, Sacai PY, Coupland SG, Sadun AA, Salomão SR. Photopic negative response using a handheld mini-ganzfeld stimulator in healthy adults: normative values, intra- and inter-session variability. Doc Ophthalmol 2020; 142:153-163. [PMID: 32681419 DOI: 10.1007/s10633-020-09784-x] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/21/2020] [Accepted: 07/08/2020] [Indexed: 10/23/2022]
Abstract
PURPOSE To determine normative values, intra- and inter-session variability for a range of parameters derived from the photopic negative response (PhNR) using a handheld mini-Ganzfeld stimulator in healthy normal adults. METHODS Light-adapted flash full-field electroretinograms (ERGs) were recorded from healthy individuals with no visual complaints, visual acuity equal to or better than 0.0 logMAR (20/20 Snellen), and negative family history for visual diseases. ERGs were recorded from both eyes using a DTL® type fiber electrode after dilation of the pupils with instillation of 1 drop of tropicamide eye drops (1%). The full-field PhNR stimulus conditions were produced by a LED-based ColorBurst™ (Diagnosys LLC, Lowell, MA, USA) handheld stimulator. Red flashes of 1, 5 and 7 cd.s/m2 on a blue background of 10 cd/m2 were presented. A-wave, b-wave and PhNR amplitude (determined by both baseline to trough-BT and peak to trough-PT) and peak times were analyzed. Normal limits were determined as 5% percentile for amplitudes and 95% percentile for latencies. Intra- and inter-session variability were assessed with Wilcoxon signed-rank test, intraclass correlation coefficient (ICC) and the coefficient of variability (COV). RESULTS Normative limits for PhNR amplitude (µV) using 1, 5 and 7 cd.s./m2 stimuli were, respectively: 20.81; 18.06 and 19.60 for BT and 69.11; 77.98; 76.51 for PT. Peak times (ms) normative limits for 1, 5 and 7 cd.s/m2 intensities were, respectively, 65.98; 78.20 and 77.96. Overall, intra-session variability assessed by coefficients of variation ranged from 1.35 to 10.28%. Inter-session variability disclosed significant intraclass correlation values for all PhNR parameters only for 1 cd.s/m2 stimuli. CONCLUSIONS The normative values provided by this study are clinically helpful in the diagnosis of inner retinal disorders, especially those affecting retinal ganglion cells such as glaucoma and other optic neuropathies. Further studies, including a larger sample with variable age range would extend the validity of the current results.
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Affiliation(s)
- Adriana Berezovsky
- Departamento de Oftalmologia e Ciências Visuais, Escola Paulista de Medicina, Universidade Federal de São Paulo, São Paulo, SP, Brazil.
| | - Rustum Karanjia
- Doheny Eye Institute, Los Angeles, California, USA.,Department of Ophthalmology, David Geffen School of Medicine at UCLA, Doheny Eye Center, Los Angeles, California, USA.,Ottawa Eye Institute, University of Ottawa, Ottawa, ON, Canada.,Ottawa Hospital Research Institute, Ottawa, ON, Canada
| | - Arthur Gustavo Fernandes
- Departamento de Oftalmologia e Ciências Visuais, Escola Paulista de Medicina, Universidade Federal de São Paulo, São Paulo, SP, Brazil
| | - Gabriel Izan Santos Botelho
- Departamento de Oftalmologia e Ciências Visuais, Escola Paulista de Medicina, Universidade Federal de São Paulo, São Paulo, SP, Brazil
| | - Tatiane Luana Novele Bueno
- Departamento de Oftalmologia e Ciências Visuais, Escola Paulista de Medicina, Universidade Federal de São Paulo, São Paulo, SP, Brazil
| | - Nívea Nunes Ferraz
- Departamento de Oftalmologia e Ciências Visuais, Escola Paulista de Medicina, Universidade Federal de São Paulo, São Paulo, SP, Brazil
| | - Paula Yuri Sacai
- Departamento de Oftalmologia e Ciências Visuais, Escola Paulista de Medicina, Universidade Federal de São Paulo, São Paulo, SP, Brazil
| | - Stuart Glenn Coupland
- Ottawa Eye Institute, University of Ottawa, Ottawa, ON, Canada.,Ottawa Hospital Research Institute, Ottawa, ON, Canada
| | - Alfredo Arrigo Sadun
- Doheny Eye Institute, Los Angeles, California, USA.,Department of Ophthalmology, David Geffen School of Medicine at UCLA, Doheny Eye Center, Los Angeles, California, USA
| | - Solange Rios Salomão
- Departamento de Oftalmologia e Ciências Visuais, Escola Paulista de Medicina, Universidade Federal de São Paulo, São Paulo, SP, Brazil
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7
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Behbahani S, Ramezani A, Karimi Moridani M, Sabbaghi H. Time-Frequency Analysis of Photopic Negative Response in CRVO Patients. Semin Ophthalmol 2020; 35:187-193. [PMID: 32586181 DOI: 10.1080/08820538.2020.1781905] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 10/24/2022]
Abstract
PURPOSE The PhNR is driven by retinal ganglion cells (RGCs). Therefore, the function of RGCs could be objectively evaluated by analyzing the PhNR. The aim of this article is to determine the effect of central retinal vein occlusion (CRVO) on PhNR and RGCs performances. METHODS Seventeen patients with CRVO were included. Full-field photopic ERGs, including PhNR, were recorded and compared with the fellow normal eyes. ERG signals were analyzed based on the standard time-domain analyses of the PhNR as well as a continuous wavelet transform (CWT) to extract time-frequency components that correspond to the PhNR using MATLAB. We obtained the main frequencies and their occurrence time from CWT. RESULTS All a-wave, b-wave, and PhNR amplitudes of CRVO eyes showed a significant reduction compared to those of the fellow eyes (P < .01, P < .001, and P < .001, respectively). The peak times of a-wave, b-wave, and PhNR were increased significantly in the CRVO eyes (P = .04, P = .04, and P = .003, respectively). The dominant f3 frequency, which corresponds to the PhNR in CRVO patients, showed a more significant decrease (P < .001) compared to other dominant frequencies (f0, f1, and f2). The occurrence time of f3 (t3) was significantly higher in the CRVO eyes (P < .001). Time-domain of the PhNR was also affected in CRVO patients (P < .001). CONCLUSION CWT allows quantifications of ERG responses, especially for PhNR. The PhNR was severely affected in CRVO eyes implicating loss of RGCs. CWT might demonstrate the severity of CRVO more precisely and identify diagnostically significant changes of ERG waveforms that are not resolved when the analysis is only limited to the time-domain measurements.
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Affiliation(s)
- Soroor Behbahani
- Department of Electrical Engineering, Garmsar Branch, Islamic Azad University , Garmsar, Iran
| | - Alireza Ramezani
- Ophthalmic Epidemiology Research Center, Shahid Beheshti University of Medical Sciences , Tehran, Iran
| | - Mohammad Karimi Moridani
- Department of Biomedical Engineering, Faculty of Health, Tehran Medical Sciences, Islamic Azad University , Tehran, Iran
| | - Hamideh Sabbaghi
- Ophthalmic Research Center, Shahid Beheshti University of Medical Sciences, Tehran, Iran.,Department of Optometry, School of Rehabilitation, Shahid Brheshti University of Medical Sciences, Tehran, Iran
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Scuderi G, Fragiotta S, Scuderi L, Iodice CM, Perdicchi A. Ganglion Cell Complex Analysis in Glaucoma Patients: What Can It Tell Us? Eye Brain 2020; 12:33-44. [PMID: 32099501 PMCID: PMC6999543 DOI: 10.2147/eb.s226319] [Citation(s) in RCA: 39] [Impact Index Per Article: 9.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/08/2019] [Accepted: 01/15/2020] [Indexed: 12/15/2022] Open
Abstract
Glaucoma is a group of optic neuropathies characterized by a progressive degeneration of retina ganglion cells (RGCs) and their axons that precedes functional changes detected on the visual field. The macular ganglion cell complex (GCC), available in commercial Fourier-domain optical coherence tomography, allows the quantification of the innermost retinal layers that are potentially involved in the glaucomatous damage, including the retinal nerve fiber (RNFL), ganglion cell and inner plexiform layers. The average GCC thickness and its related parameters represent a reliable biomarker in detecting preperimetric glaucomatous damage. The most accurate GCC parameters are represented by average and inferior GCC thicknesses, and they can be associated with progressive visual field loss. Although the diagnostic accuracy increases with more severe glaucomatous damage and higher signal strength values, it is not affected by increasing axial length, resulting in a more accurate discrimination of glaucomatous damage in myopic eyes with respect to the traditional RNFL thickness. The analysis of the structure-function relationship revealed a good agreement between the loss in retinal sensitivity and GCC thickness. The use of a 10-2° visual field grid, adjusted for the anatomical RGCs displacement, describes more accurately the relationship between RGCs thickness and visual field sensitivity loss.
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Affiliation(s)
- Gianluca Scuderi
- NESMOS Department, Ophthalmology Unit, S. Andrea Hospital, University of Rome "La Sapienza", Rome, Italy
| | - Serena Fragiotta
- NESMOS Department, Ophthalmology Unit, S. Andrea Hospital, University of Rome "La Sapienza", Rome, Italy
| | - Luca Scuderi
- Ophthalmology Unit, Department of Sense Organs, Azienda Policlinico Umberto I, University of Rome "La Sapienza", Rome, Italy
| | | | - Andrea Perdicchi
- NESMOS Department, Ophthalmology Unit, S. Andrea Hospital, University of Rome "La Sapienza", Rome, Italy
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Morny EKA, Patel K, Votruba M, Binns AM, Margrain TH. The Relationship Between the Photopic Negative Response and Retinal Ganglion Cell Topography. Invest Ophthalmol Vis Sci 2019; 60:1879-1887. [PMID: 31042794 DOI: 10.1167/iovs.18-25272] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/24/2022] Open
Abstract
Purpose To assess the topographic relationship between the photopic negative response (PhNR) and retinal ganglion cell distribution in healthy individuals. Method Data was recorded from 16 healthy participants. The amplitude of PhNRs obtained in response to focal long duration (250 ms) and brief flash (5 ms), red (660 nm) on blue (469 nm) stimuli of increasing size (5° - full field) were measured. The number of retinal ganglion cell receptive fields (RGCf) in each stimulus area was established from the literature and regression analysis used to determine the relationships between: PhNR amplitude and number of RGCfs stimulated, PhNR density and the RGCf density and response per RGCf as a function of eccentricity. Results The overall amplitude of the PhNR increased with stimulus size and the response density declined from ∼0.1 μV/deg in the macular region to ∼0.003 μV/deg approximately 45° from the fovea. Contrary to expectations, the relationship between the PhNR and number of RGCf was nonlinear, the response from more eccentric neurons being about three times greater than those in the macular region. Conclusions Although the amplitude of the PhNR broadly maps on to the topographic distribution of RGCf the increase in PhNR amplitude with increasing eccentricity is only partly explained by RGCf numbers. Increases in the PhNR amplitude may be due to topographic variations in the contributions from other non-RGC neurons, as well as eccentricity-related morphologic and physiologic differences in RGCs.
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Affiliation(s)
- Enyam Komla A Morny
- Department of Optometry and Vision Science, University of Cape Coast, Cape Coast, Ghana
| | - Kishan Patel
- School of Optometry and Vision Sciences, Cardiff University, Cardiff, Wales, United Kingdom
| | - Marcela Votruba
- School of Optometry and Vision Sciences, Cardiff University, Cardiff, Wales, United Kingdom.,Eye Unit, University Hospital of Wales, Cardiff, Wales, United Kingdom
| | - Alison M Binns
- School of Health Sciences, City, University of London, London, United Kingdom
| | - Tom H Margrain
- School of Optometry and Vision Sciences, Cardiff University, Cardiff, Wales, United Kingdom
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10
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Honda H, Anraku A, Ishida K, Enomoto N, Tomita G. Relationship between Macular Vessel Density and Focal Electroretinograms in Early Normal Tension Glaucoma. Curr Eye Res 2019; 44:753-759. [DOI: 10.1080/02713683.2019.1593464] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/23/2022]
Affiliation(s)
- Hakuei Honda
- Department of Ophthalmology, Toho University Graduate School of Medicine, Tokyo, Japan
- Department of Ophthalmology, Toho University Ohashi Medical Center, Tokyo, Japan
| | - Ayako Anraku
- Department of Ophthalmology, Toho University Ohashi Medical Center, Tokyo, Japan
| | - Kyoko Ishida
- Department of Ophthalmology, Toho University Ohashi Medical Center, Tokyo, Japan
| | - Nobuko Enomoto
- Department of Ophthalmology, Toho University Ohashi Medical Center, Tokyo, Japan
| | - Goji Tomita
- Department of Ophthalmology, Toho University Ohashi Medical Center, Tokyo, Japan
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11
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Wu Z, Hadoux X, Hui F, Sarossy MG, Crowston JG. Photopic Negative Response Obtained Using a Handheld Electroretinogram Device: Determining the Optimal Measure and Repeatability. Transl Vis Sci Technol 2016; 5:8. [PMID: 27540494 PMCID: PMC4981488 DOI: 10.1167/tvst.5.4.8] [Citation(s) in RCA: 18] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/22/2016] [Accepted: 05/24/2016] [Indexed: 12/01/2022] Open
Abstract
Purpose To determine the measure of the photopic negative response (PhNR) of the full-field electroretinogram (ERG) that exhibits the optimal level of test-retest repeatability, and examine its repeatability under different conditions using a handheld, nonmydriatic ERG system and self-adhering skin electrodes. Methods Multiple ERG recordings (using 200 sweeps each) were performed in both eyes of 20 normal participants at two different sessions to compare its coefficient of repeatability (CoR; where 95% of the test-retest difference is expected to lie) between different PhNR measures and under different testing conditions (within and between examiners, and between sessions). Results The ratio between the PhNR trough to b-wave peak and b-wave peak to a-wave trough amplitude (PhNR/B ratio) exhibited the lowest CoR relative to its effective dynamic range (30 ± 4%) when including three recordings. There were no significant changes in the PhNR/B ratio over seven measurements (4 right and 3 left eyes) at either session (P ≥ 0.100), or significant difference in its CoR between different testing conditions (P = 0.314). Conclusion The PhNR/B ratio was the measure that minimized variability, and its measurements using a novel handheld ERG system with self-adhering skin electrodes and the protocols described in this study were comparable under different testing conditions and over multiple recordings. Translational Relevance The PhNR can be measured for clinical and research purposes using a simple-to-implement technique that is consistent within and between visits, and also between examiners.
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Affiliation(s)
- Zhichao Wu
- Centre for Eye Research Australia, Royal Victorian Eye and Ear Hospital, East Melbourne, Australia ; Ophthalmology, Department of Surgery, The University of Melbourne, Melbourne, Australia
| | - Xavier Hadoux
- Centre for Eye Research Australia, Royal Victorian Eye and Ear Hospital, East Melbourne, Australia ; Ophthalmology, Department of Surgery, The University of Melbourne, Melbourne, Australia
| | - Flora Hui
- Centre for Eye Research Australia, Royal Victorian Eye and Ear Hospital, East Melbourne, Australia ; Ophthalmology, Department of Surgery, The University of Melbourne, Melbourne, Australia
| | - Marc G Sarossy
- Centre for Eye Research Australia, Royal Victorian Eye and Ear Hospital, East Melbourne, Australia ; Ophthalmology, Department of Surgery, The University of Melbourne, Melbourne, Australia
| | - Jonathan G Crowston
- Centre for Eye Research Australia, Royal Victorian Eye and Ear Hospital, East Melbourne, Australia ; Ophthalmology, Department of Surgery, The University of Melbourne, Melbourne, Australia
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12
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Kinoshita J, Takada S, Iwata N, Tani Y. Comparison of photopic negative response (PhNR) between focal macular and full-field electroretinograms in monkeys. Doc Ophthalmol 2016; 132:177-87. [PMID: 27071393 DOI: 10.1007/s10633-016-9538-x] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/28/2015] [Accepted: 04/06/2016] [Indexed: 11/25/2022]
Abstract
PURPOSE To compare the characteristics of the photopic negative response (PhNR) between the focal macular and full-field electroretinograms (ERGs) in monkeys. METHODS Both focal macular and full-field photopic ERGs were recorded in four cynomolgus monkeys under identical stimulus and recording conditions except for which area of the retina was illuminated. The luminance and duration of red flash stimuli were varied in the presence of steady blue background illumination. These ERGs were recorded before and after intravitreal injection of tetrodotoxin (TTX). RESULTS Several differences were identified between the focal macular and full-field ERGs, including: (1) The PhNR/b-wave amplitude ratio was higher in the focal macular than in the full-field ERGs, and (2) the stimulus threshold of the focal macular PhNR was lower than that of the full-field PhNR. For both macular and full-field stimulation conditions, (1) PhNR amplitude generally increased with increasing stimulus luminance; (2) PhNR implicit time was independent of the stimulus luminance; (3) PhNR amplitude and implicit time increased with increasing stimulus duration up to 50 ms, while a further increase in stimulus duration produced no change in amplitude or implicit time; and (4) PhNR amplitude was selectively attenuated by TTX. CONCLUSIONS Both the focal macular and full-field PhNRs reflect the functional properties of the inner retina including the retinal ganglion cells (RGCs). Relative to the b-wave, the contribution is weighted more heavily in the focal macular than in the full-field PhNR. Furthermore, these results support the idea that the focal macular PhNR can be an indicator of the function of the macular RGCs.
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Affiliation(s)
- Junzo Kinoshita
- Medicinal Safety Research Laboratories, Daiichi Sankyo Co., Ltd., 1-16-13 Kitakasai, Edogawa-ku, Tokyo, 134-8630, Japan.
| | - Shunsuke Takada
- Medicinal Safety Research Laboratories, Daiichi Sankyo Co., Ltd., 1-16-13 Kitakasai, Edogawa-ku, Tokyo, 134-8630, Japan
| | - Noriaki Iwata
- Medicinal Safety Research Laboratories, Daiichi Sankyo Co., Ltd., 1-16-13 Kitakasai, Edogawa-ku, Tokyo, 134-8630, Japan
| | - Yoshiro Tani
- Medicinal Safety Research Laboratories, Daiichi Sankyo Co., Ltd., 1-16-13 Kitakasai, Edogawa-ku, Tokyo, 134-8630, Japan
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Khanal S, Davey PG, Racette L, Thapa M. Comparison of retinal nerve fiber layer and macular thickness for discriminating primary open-angle glaucoma and normal-tension glaucoma using optical coherence tomography. Clin Exp Optom 2016; 99:373-81. [PMID: 26996257 DOI: 10.1111/cxo.12366] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/27/2015] [Revised: 09/11/2015] [Accepted: 11/03/2015] [Indexed: 11/26/2022] Open
Abstract
PURPOSE The aim of this study was to evaluate the discrimination capabilities of macular and peripapillary retinal nerve fiber layer (pRNFL) thickness parameters as measured using spectral domain optical coherence tomography (SD-OCT) between primary open-angle glaucoma (POAG) and normal-tension glaucoma (NTG). METHODS A total of 90 subjects were enrolled: 30 healthy subjects, 30 subjects with POAG and 30 subjects with NTG, consecutively. Retinal nerve fiber layer thickness, macular thickness and volume measurements were obtained with circular and radial SD-OCT scans. All parameters were compared between groups using an analysis of variance test. Areas under receiver-operating characteristic (AROC) curves with sensitivities at specificities greater than or equal to 90 per cent were generated to compare discrimination capabilities of various parameters between POAG and NTG. RESULTS Macular thickness and volume measurements were the highest in normal subjects, followed by NTG and POAG (p < 0.05). Average retinal nerve fiber layer thickness had perfect discrimination for normal-POAG (AROC: 1.000; sensitivity: 100 per cent) and near perfect discrimination for normal-NTG (AROC: 0.979; sensitivity: 93 per cent) as well as NTG-POAG pairs (AROC: 0.900; sensitivity: 60 per cent). Inferior outer macular thickness (IOMT) and total volume were the best macular thickness and volume parameters having similar AROCs and sensitivities between normal and POAG (IOMT, AROC: 0.987; sensitivity: 92 per cent and total volume, AROC: 0.997; sensitivity: 97 per cent), normal and NTG (IOMT, AROC: 0.862, sensitivity: 47 per cent and total volume, AROC: 0.898, sensitivity: 67 per cent) and also between NTG and POAG (IOMT, AROC: 0.910, sensitivity: 53 per cent and total volume, AROC: 0.922, sensitivity: 77 per cent). In each comparison group, there was no statistically significant difference in AROCs between average retinal nerve fiber layer and inferior outer macular thickness, as well as total volume. CONCLUSIONS The macular parameters offer comparable performance to pRNFL parameters for the discrimination of NTG and POAG. Average retinal nerve fiber layer thickness, total macular volume and inferior outer macular thickness were the best SD-OCT parameters with superior discriminating capabilities.
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Affiliation(s)
- Safal Khanal
- School of Optometry and Vision Science, Faculty of Medical and Health Sciences, University of Auckland, Auckland, New Zealand. , .,College of Optometry, Western University of Health Sciences, Pomona, California, USA. ,
| | - Pinakin Gunvant Davey
- College of Optometry, Western University of Health Sciences, Pomona, California, USA
| | - Lyne Racette
- Eugene and Marilyn Glick Eye Institute, Indiana University School of Medicine, Indianapolis, Indiana, USA
| | - Madhu Thapa
- BP Koirala Lions Center for Ophthalmic Studies, Institute of Medicine, Kathmandu, Nepal
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Wu Z, Hadoux X, Fan Gaskin JC, Sarossy MG, Crowston JG. Measuring the Photopic Negative Response: Viability of Skin Electrodes and Variability Across Disease Severities in Glaucoma. Transl Vis Sci Technol 2016; 5:13. [PMID: 26998406 PMCID: PMC4795588 DOI: 10.1167/tvst.5.2.13] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/01/2015] [Accepted: 02/12/2016] [Indexed: 12/05/2022] Open
Abstract
PURPOSE The purpose of this study was to determine the feasibility of measuring the photopic negative response (PhNR) of the full-field electroretinogram (ERG) using skin electrodes compared to conjunctival electrodes and its test-retest variability over a range of disease severities in open-angle glaucoma. METHODS Recordings were performed twice (100 sweeps each) within the same session in 43 eyes of 23 participants with glaucoma to determine its intrinsic variability. The ratio between the PhNR and B-wave amplitude (PhNR/B ratio) was determined for each trace and computed across 5 to 100 sweeps of each recording. Spectral-domain optical coherence tomography was used to measure the average peripapillary retinal nerve fiber layer (RNFL) thickness. RESULTS The PhNR/B ratio and its magnitude of variability were not significantly different between skin and conjunctival electrodes (P ≤ 0.197), and the degree of variability decreased substantially with increasing number of sweeps. For skin electrodes, the intraclass correlation coefficient was 0.89 and 0.91 for right and left eyes, respectively. The variability of the PhNR/B ratio decreased with lower RNFL thickness values and larger B-wave amplitudes (P ≤ 0.002). CONCLUSIONS Skin electrodes are a viable alternative to conjunctival electrodes when measuring the PhNR in open angle glaucoma, and increasing the number of sweeps substantially reduced its intrinsic variability; the extent of variability was also lower with worsening disease severity. TRANSLATIONAL RELEVANCE The feasibility of performing ERG recordings widely across a range of disease severities in glaucoma can be achieved through using skin electrodes and increasing the number of sweeps performed to improve measurement repeatability.
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Affiliation(s)
- Zhichao Wu
- Centre for Eye Research Australia, Royal Victorian Eye and Ear Hospital, East Melbourne, Australia
- Ophthalmology, Department of Surgery, The University of Melbourne, Melbourne, Australia
| | - Xavier Hadoux
- Centre for Eye Research Australia, Royal Victorian Eye and Ear Hospital, East Melbourne, Australia
- Ophthalmology, Department of Surgery, The University of Melbourne, Melbourne, Australia
| | - Jennifer C. Fan Gaskin
- Centre for Eye Research Australia, Royal Victorian Eye and Ear Hospital, East Melbourne, Australia
- Ophthalmology, Department of Surgery, The University of Melbourne, Melbourne, Australia
| | - Marc G. Sarossy
- Centre for Eye Research Australia, Royal Victorian Eye and Ear Hospital, East Melbourne, Australia
- Ophthalmology, Department of Surgery, The University of Melbourne, Melbourne, Australia
| | - Jonathan G. Crowston
- Centre for Eye Research Australia, Royal Victorian Eye and Ear Hospital, East Melbourne, Australia
- Ophthalmology, Department of Surgery, The University of Melbourne, Melbourne, Australia
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Liu K, Wang N, Peng X, Yang D, Wang C, Zeng H. Long-term effect of laser-induced ocular hypertension on the cone electroretinogram and central macular thickness in monkeys. Photomed Laser Surg 2016; 32:371-8. [PMID: 24992271 DOI: 10.1089/pho.2013.3693] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022] Open
Abstract
OBJECTIVE The purpose of this study was to investigate the long-term effect of laser-induced ocular hypertension on the cone electroretinogram (ERG) and retinal thickness in monkeys. BACKGROUND DATA Degeneration of retinal nerve fiber layer (RNFL) and loss of retinal ganglion cells in the primate glaucoma model have been confirmed by histological studies and optical coherence tomography (OCT) images. However, it remains unclear whether the outer retina distal to the RGCs (e.g., photoreceptors) is involved in histological studies and in functional test. MATERIALS AND METHODS Subjects were five monkeys with high intraocular pressure (IOP) induced in the right eye by laser. Six years after the laser coagulation of the mid-trabecular meshwork, RNFL, ganglion cell complex (GCC), central macular thickness (CMT), and the thickness of outer retinal layer (ORL) were measured by OCT. The photopic responses of ERG were recorded in response to red flashes on a blue background. The maximum cone amplitude (Rcone) and cone sensitivity (Scone) were calculated. RESULTS Enlarged cup-to-disc (C/D) ratio was found in the lasered eyes. RNFL and GCC were significantly thinner in the lasered eyes (p<0.05), but no significant differences were found in CMT and the thickness of ORL compared with fellow eyes (p>0.05). Mean amplitude of the photopic negative response (PhNR), Mean Rcone were significantly lower in the lasered eye (p<0.05), and no significant differences of Scone were found between the two eyes (p>0.05). CONCLUSIONS Long-term ocular hypertension induced by laser affects the function of cone photoreceptor in monkeys.
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Affiliation(s)
- Kegao Liu
- 1 Beijing Ophthalmology and Visual Science Key Laboratory, Beijing Tongren Eye Center, Beijing Tongren Hospital, Capital Medical University , Beijing, China
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Hong EH, Shin YU, Lim HW, Kang MH, Cho HY, Seong M. RNFL and Ganglion Cell Complex Thickness in Normal Hemifield According to the Severity of Glaucoma. JOURNAL OF THE KOREAN OPHTHALMOLOGICAL SOCIETY 2016. [DOI: 10.3341/jkos.2016.57.4.614] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/23/2022]
Affiliation(s)
- Eun Hee Hong
- Department of Ophthalmology, Hanyang University Guri Hospital, Hanyang University College of Medicine, Guri, Korea
| | - Yong Un Shin
- Department of Ophthalmology, Hanyang University Guri Hospital, Hanyang University College of Medicine, Guri, Korea
| | - Han Woong Lim
- Department of Ophthalmology, Hanyang University Guri Hospital, Hanyang University College of Medicine, Guri, Korea
| | - Min Ho Kang
- Department of Ophthalmology, Hanyang University Guri Hospital, Hanyang University College of Medicine, Guri, Korea
| | - Hee Yoon Cho
- Department of Ophthalmology, Hanyang University Guri Hospital, Hanyang University College of Medicine, Guri, Korea
| | - Mincheol Seong
- Department of Ophthalmology, Hanyang University Guri Hospital, Hanyang University College of Medicine, Guri, Korea
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Correlation between N2 amplitude of multifocal ERGs and retinal sensitivity and retinal nerve fiber layer thickness in glaucomatous eyes. Doc Ophthalmol 2015; 131:197-206. [PMID: 26521929 DOI: 10.1007/s10633-015-9519-5] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/08/2015] [Accepted: 10/28/2015] [Indexed: 10/22/2022]
Abstract
PURPOSE To determine whether there are significant correlations between the N2 amplitude of the multifocal electroretinograms (mfERGs) and the retinal sensitivity and retinal nerve fiber layer (RNFL) thickness in glaucomatous and normal eyes. METHODS Thirty-eight glaucomatous and 11 normal eyes were studied. The mfERGs were elicited by red stimuli presented on a blue background. The responses from the central five elements within a 20° stimulated area were analyzed. The retinal sensitivity was determined by Humphrey Field Analyzer and the RNFL thickness by spectral-domain optical coherence tomography. The correlations between the N2 amplitude and the retinal sensitivity and the RNFL thickness were calculated. RESULTS The N2 amplitude was significantly smaller in the glaucomatous eyes than the normal eyes in all areas (P < 0.05). There was a significant correlation between the N2 amplitude and the retinal sensitivity (1/Lambert linear unit) of the HFA for the superior retina (r = 0.36, P = 0.01), for the central retina (r = 0.54, P < 0.0001), and for the inferior retina (r = 0.51, P = 0.0001). There were significant correlations between the N2 amplitude and the RNFL thicknesses in the superior retina (r = 0.49, P = 0.0003), the central retina (r = 0.79, P < 0.0001), and the inferior retina (r = 0.52, P = 0.0001) for both normal and glaucomatous eyes. CONCLUSIONS These results indicate that the activity of the retinal ganglion cells contribute to the amplitude of the N2 of the mfERGs and thus can be used as an objective monitor of retinal ganglion cell function.
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Machida S, Kaneko M, Kurosaka D. Regional Variations in Correlation between Photopic Negative Response of Focal Electoretinograms and Ganglion Cell Complex in Glaucoma. Curr Eye Res 2014; 40:439-49. [DOI: 10.3109/02713683.2014.922196] [Citation(s) in RCA: 29] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022]
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Kaneko M, Machida S, Hoshi Y, Kurosaka D. Alterations of photopic negative response of multifocal electroretinogram in patients with glaucoma. Curr Eye Res 2014; 40:77-86. [PMID: 24832792 DOI: 10.3109/02713683.2014.915575] [Citation(s) in RCA: 30] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022]
Abstract
PURPOSE To determine the effect of glaucoma on the multifocal electroretinograms (ERGs) (mfERGs) elicited by low-frequency stimuli. METHODS Forty-four patients with open-angle glaucoma and 15 normal subjects were studied. The stimulus frequency was 6.25 Hz, and the stimulus was a circle with a 6.8° radius that was centered on the fovea (center). MfERGs were also elicited by a quarter of an annulus placed around the macula (superior/temporal; inferior/temporal; superior/nasal; and inferior/nasal quadrants). The radius of the inner border of the annulus was 6.8° and that of the outer border was 20°. The actual sensitivity was determined by standard automated perimetry. The thickness of the ganglion cell complex (GCC) was measured by optical coherence tomography. RESULTS The mfERGs consisted of a negative wave (N1) followed by a positive wave (P1), and followed by a slow negative wave (N2). There were no significant differences in the response densities of N1 and P1 between the normal control and glaucomatous eyes in any areas. The N2 response density was significantly reduced with the severity of glaucoma in the center. There was a significant reduction even at an early stage of glaucoma compared to control values. In the center, the N2 response density was significantly correlated with the GCC thickness and mean sensitivity. However, in other stimulus areas, there was no significant reduction of any components of the mfERGs. CONCLUSIONS These results suggest that the N2 component of the slow-sequence mfERGs is affected by glaucoma in the central retinal area. Regional variations in the contribution of the retinal ganglion cell activity to the N2 should be considered when examining the mfERGs in glaucoma patients.
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Affiliation(s)
- Muneyoshi Kaneko
- Department of Ophthalmology, Iwate Medical University School of Medicine , Uchimaru, Morioka, Iwate , Japan
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Machida S, Tamada K, Ohzeki T, Gotoh Y, Kurosaka D. Differences in functional loss associated with ganglion cell complex thinning between patients with glaucoma and postoperative macular hole. Curr Eye Res 2014; 39:845-52. [PMID: 24559381 DOI: 10.3109/02713683.2013.879596] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022]
Abstract
PURPOSE To compare the changes in the photopic negative response (PhNR) of the focal macular electoretinogram (fmERG) caused by a thinning of the ganglion cell complex (GCC) between patients with open angle glaucoma (OAG) and after successful macular hole (MH) surgery. METHODS Twenty-seven eyes of 27 OAG patients (OAG group), 28 eyes of 28 MH patients (MH group) and 23 eyes of 23 normal volunteers (control group) were studied. The OAG patients had early stage of glaucoma. The MH patients had been successfully treated with vitrectomy 12 months earlier. The averaged GCC thickness in the macular area (15 degree in a diameter) was measured by SD-OCT. The fmERGs were elicited by a 15° stimulus centered on the fovea. RESULTS The GCC was significantly thinner in the OAG and MH groups than in the control group (p < 0.0001). The PhNR amplitude and PhNR/b-wave amplitude ratio were significantly reduced in the OAG group compared to the control (p < 0.0001), while no significant reduction of the PhNR amplitude was observed in the MH group. The PhNR amplitude and PhNR/b-wave amplitude ratio were significantly correlated with the GCC thickness in the OAG group (R(2 )= 0.741 for the PhNR amplitude, R(2 )= 0.564 for the PhNR/b-wave amplitude ratio, p < 0.0001 for both). There were significant differences in the slopes of regression lines plotting the GCC thickness and the PhNR amplitude (p < 0.05) or the PhNR/b-wave amplitude ratio (p < 0.0005) between the OAG and MH groups. CONCLUSIONS The thinning of the GCC affects the RGC function in the macula area differently for patients with OAG and patients after MH closure.
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Affiliation(s)
- Shigeki Machida
- Department of Ophthalmology, Iwate Medical University, School of Medicine , Morioka , Japan
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Clinical applications of the photopic negative response to optic nerve and retinal diseases. J Ophthalmol 2012; 2012:397178. [PMID: 23133741 PMCID: PMC3486014 DOI: 10.1155/2012/397178] [Citation(s) in RCA: 55] [Impact Index Per Article: 4.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/18/2012] [Accepted: 09/16/2012] [Indexed: 11/22/2022] Open
Abstract
The photopic negative response (PhNR) in response to a brief flash is a negative-going wave following the b-wave of the cone electroretinogram (ERG) that is driven by retinal ganglion cells (RGCs). The function of RGCs is objectively evaluated by analysing the PhNR. We reviewed articles regarding clinical use of the PhNR. The PhNR was well correlated with the visual sensitivity obtained by standard automated perimetry and morphometric parameters of the inner retina and optic nerve head in optic nerve and retinal diseases. Moreover, combining the PhNR with focal or multifocal ERG techniques enables the objective assessment of local function of RGCs. The PhNR is therefore likely to become established as an objective functional test for optic nerve and retinal diseases involving RGC injury.
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Hori N, Komori S, Yamada H, Sawada A, Nomura Y, Mochizuki K, Yamamoto T. Assessment of macular function of glaucomatous eyes by multifocal electroretinograms. Doc Ophthalmol 2012; 125:235-47. [DOI: 10.1007/s10633-012-9351-0] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/28/2012] [Accepted: 08/20/2012] [Indexed: 10/27/2022]
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Firat PG, Doganay S, Demirel EE, Colak C. Comparison of ganglion cell and retinal nerve fiber layer thickness in primary open-angle glaucoma and normal tension glaucoma with spectral-domain OCT. Graefes Arch Clin Exp Ophthalmol 2012; 251:831-8. [DOI: 10.1007/s00417-012-2114-5] [Citation(s) in RCA: 36] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/10/2012] [Revised: 06/30/2012] [Accepted: 07/07/2012] [Indexed: 12/19/2022] Open
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Na JH, Kook MS, Lee Y, Yu SJ, Choi J. Detection of macular and circumpapillary structural loss in normal hemifield areas of glaucomatous eyes with localized visual field defects using spectral-domain optical coherence tomography. Graefes Arch Clin Exp Ophthalmol 2011; 250:595-602. [DOI: 10.1007/s00417-011-1864-9] [Citation(s) in RCA: 28] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/21/2011] [Revised: 11/02/2011] [Accepted: 11/08/2011] [Indexed: 11/25/2022] Open
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