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Hermas A, Tsilfidis C, Karanjia R, Miller G, Kantungane AL, El-Salibi A, Kherani IN, Bali S, Coupland S. Sensitivity and specificity of the uniform field electroretinogram in glaucoma detection in comparison to the pattern electroretinogram. Doc Ophthalmol 2024; 148:97-106. [PMID: 38243039 DOI: 10.1007/s10633-023-09960-9] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/28/2022] [Accepted: 12/06/2023] [Indexed: 01/21/2024]
Abstract
PURPOSE To determine the ability of the photopic negative response (PhNR) of the uniform field electroretinogram (UF-ERG) to identify early glaucomatous changes in comparison to the checkerboard and bar stimuli of the pattern electroretinogram (PERG). METHODS Forty-nine glaucoma patients were classified into two groups: glaucoma-suspect (23 eyes) and early to moderate glaucoma (30 eyes), based on their clinical examination and the results of standard automated perimetry. Thirty patients (30 eyes) with intraocular pressures (IOP) of 21 mmHg or less, with no history of reported high IOP, were included as controls. PERG and UF-ERG recordings were obtained on a Diagnosys D-341 Attaché-Envoy System. Visual field testing was done only for glaucoma-suspect and glaucoma patients. RESULTS All three tests (PERG bar stimulus, PERG checkerboard stimulus and PhNR) displayed significantly prolonged peak times for glaucoma and glaucoma-suspect patients, with delays ranging from 7.8 to 14.8%, depending on the test. The PERG bar stimulus also showed a significantly lower N95 amplitude for both glaucoma groups (with reductions of 26.0% and 33.0% for glaucoma-suspect and glaucoma groups, respectively). The PERG checkerboard N95 amplitude component had high sensitivity for detecting glaucoma patients but a low specificity (97% and 37%, respectively; AUC = 0.61). Overall, the PhNR peak time showed the highest sensitivity and specificity (77% and 90%, respectively; AUC = 0.87). CONCLUSIONS PERG bar stimuli and the PhNR of the UF-ERG can be used in the clinical setting to detect glaucoma-related changes in glaucoma-suspect and glaucoma patients. However, our data confirm that the PhNR peak time has the best combined sensitivity and specificity.
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Affiliation(s)
- Asma Hermas
- Regenerative Medicine Program, Ottawa Hospital Research Institute, Ottawa, ON, Canada.
- Department of Cellular and Molecular Medicine, University of Ottawa, Ottawa, ON, Canada.
| | - Catherine Tsilfidis
- Department of Cellular and Molecular Medicine, University of Ottawa, Ottawa, ON, Canada
- Department of Ophthalmology, University of Ottawa, Ottawa, ON, Canada
- Neuroscience Program, Ottawa Hospital Research Institute, Ottawa, ON, Canada
| | - Rustum Karanjia
- Regenerative Medicine Program, Ottawa Hospital Research Institute, Ottawa, ON, Canada
- Department of Ophthalmology, University of Ottawa, Ottawa, ON, Canada
- Neuroscience Program, Ottawa Hospital Research Institute, Ottawa, ON, Canada
- University of Ottawa Eye Institute, Ottawa, ON, Canada
| | - Garfield Miller
- Regenerative Medicine Program, Ottawa Hospital Research Institute, Ottawa, ON, Canada
- Department of Ophthalmology, University of Ottawa, Ottawa, ON, Canada
- University of Ottawa Eye Institute, Ottawa, ON, Canada
| | - Ange-Lynca Kantungane
- Regenerative Medicine Program, Ottawa Hospital Research Institute, Ottawa, ON, Canada
- University of Ottawa Eye Institute, Ottawa, ON, Canada
| | | | - Irfan N Kherani
- Department of Ophthalmology and Visual Sciences, University of Toronto, Toronto, ON, Canada
| | - Shveta Bali
- University of Ottawa Eye Institute, Ottawa, ON, Canada
| | - Stuart Coupland
- Regenerative Medicine Program, Ottawa Hospital Research Institute, Ottawa, ON, Canada
- Department of Cellular and Molecular Medicine, University of Ottawa, Ottawa, ON, Canada
- Department of Ophthalmology, University of Ottawa, Ottawa, ON, Canada
- Neuroscience Program, Ottawa Hospital Research Institute, Ottawa, ON, Canada
- University of Ottawa Eye Institute, Ottawa, ON, Canada
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Gallo Afflitto G, Chou TH, Swaminathan SS, Aiello F, Gedde SJ, Nucci C, Porciatti V. Pattern Electroretinogram in Ocular Hypertension, Glaucoma Suspect and Early Manifest Glaucoma Eyes: A Systematic Review and Meta-analysis. OPHTHALMOLOGY SCIENCE 2023; 3:100322. [PMID: 37334035 PMCID: PMC10272507 DOI: 10.1016/j.xops.2023.100322] [Citation(s) in RCA: 5] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 02/02/2023] [Revised: 04/06/2023] [Accepted: 04/24/2023] [Indexed: 06/20/2023]
Abstract
Topic To provide standardized confidence limits of the transient pattern electroretinogram (tPERG) P50 and N95 and steady state pattern electroretinogram (ssPERG) amplitudes in normal controls as compared to ocular hypertension (OHT), glaucoma suspect (GS), or early manifest glaucoma (EMG) eyes. Clinical Relevance The identification of standardized confidence limits in the context of pattern electroretinogram (PERG) might overcome the high intrinsic variability of the measure, and it might lead to a more intuitive understanding of the results as well as to an easier comparison of data from multiple tests, sites, and operators. Methods The study protocol was prospectively registered on the International Prospective Register of Systematic Reviews (ID: CRD42022370032). A literature search was conducted on PubMed, Web of Science, and Scopus. Studies comparing PERG raw data in normal control eyes as compared to OHT, GS, or EMG were included. The risk of bias was assessed using the National Institute for Health and Clinical Excellence quality assessment tool. The main outcome was the P50, N95, and ssPERG amplitude difference between the control and the study groups' eyes. The standardized mean difference was calculated as a measure of the effect size for the primary outcome. A subanalysis was conducted based on the type of electrodes adopted for the PERG measurements (invasive vs. noninvasive). Results Of the 4580 eligible papers, only 23 were included (1754 eyes). Statistically significant amplitude differences were found in the P50, N95, and ssPERG amplitudes between normal controls and OHT, GS, and EMG eyes. The highest standardized mean difference values were observed in the ssPERG amplitude in all 3 sets of comparison. The subanalysis did not reveal any statistically significant differences between invasive and noninvasive recording strategies. Conclusions The use of standardized values as the main outcome measures in the context of the PERG data analysis is a valid approach, normalizing several confounding factors which have affected the clinical utility of PERG both for individual patients and in clinical trials. Steady state PERG apparently better discriminates diseased eyes compared to tPERG. The adoption of skin-active electrodes is able to adequately discriminate between healthy and diseased statuses. Financial Disclosures Proprietary or commercial disclosure may be found after the references.
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Affiliation(s)
- Gabriele Gallo Afflitto
- Bascom Palmer Eye Institute, University of Miami Miller School of Medicine, Miami, Florida
- Ophthalmology Unit, Department of Experimental Medicine, University of Rome “Tor Vergata”, Rome, Italy
| | - Tsung-Han Chou
- Bascom Palmer Eye Institute, University of Miami Miller School of Medicine, Miami, Florida
| | - Swarup S. Swaminathan
- Bascom Palmer Eye Institute, University of Miami Miller School of Medicine, Miami, Florida
| | - Francesco Aiello
- Ophthalmology Unit, Department of Experimental Medicine, University of Rome “Tor Vergata”, Rome, Italy
| | - Steven J. Gedde
- Bascom Palmer Eye Institute, University of Miami Miller School of Medicine, Miami, Florida
| | - Carlo Nucci
- Ophthalmology Unit, Department of Experimental Medicine, University of Rome “Tor Vergata”, Rome, Italy
| | - Vittorio Porciatti
- Bascom Palmer Eye Institute, University of Miami Miller School of Medicine, Miami, Florida
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Tirsi A, Gliagias V, Sheha H, Patel B, Moehringer J, Tsai J, Gupta R, Obstbaum SA, Tello C. Retinal Ganglion Cell Functional Recovery after Intraocular Pressure Lowering Treatment Using Prostaglandin Analogs in Glaucoma Suspects: A Prospective Pilot Study. J Curr Glaucoma Pract 2023; 17:178-190. [PMID: 38269268 PMCID: PMC10803274 DOI: 10.5005/jp-journals-10078-1423] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/23/2023] [Accepted: 10/10/2023] [Indexed: 01/26/2024] Open
Abstract
Aim and background To evaluate the ability of pattern electroretinogram (PERG) to detect improvement of retinal ganglion cell (RGC) function in glaucoma suspects (GS) after medically reducing intraocular pressure (IOP) using prostaglandin analog drops. Materials and methods Six subjects (eight eyes) received topical IOP lowering treatment based on their clinical examination and were observed at Manhattan Eye, Ear & Throat Hospital over an average of 3.1 ± 2.2 months. During this time, participants underwent a full ophthalmologic exam and were evaluated with a Humphrey visual field analyzer (HFA) 24-2 [24-2 mean deviation (MD), 24-2 pattern standard deviation (PSD), and 24-2 visual field indices (VFI)], Diopsys NOVA PERG optimized for glaucoma [magnitude (Mag), magnitudeD (MagD), and magnitudeD/magnitude ratio (MagD/Mag ratio)] and optical coherence tomography (OCT)-derived average retinal nerve fiber layer thickness (avRNFLT) and average ganglion cell layer + inner plexiform layer (avGCL + IPL) thicknesses at baseline visit (pretreatment) and 3 months later (posttreatment). Goldman applanation tonometry was used to measure IOP at each visit. Paired sample t-tests were conducted to determine the statistical significance of the change in IOP, HFA indices, PERG parameters, and OCT thickness measurements between the two visits. Results Lowering IOP by 22.29% resulted in a significant increase (32.98 and 15.49%) in MagD [t (7) = -3.174, 95% confidence interval (CI) = -0.53, -0.08, p = 0.016] and MagD/Mag ratio [t (7) = -3.233, 95% CI = -0.20, -0.03, p = 0.014], respectively. There was a positive percentage change for all variables of interest, however, 24-2 MD, Mag, avRNFLT, and GCL+ IPLT did not reach statistical significance. Conclusion After reducing IOP by 22.29% for a duration of 3.1 months, the PERG parameters, MagD and MagD/Mag ratio, significantly improved by 32.98 and 15.49%, respectively. Clinical significance Pattern electroretinogram (PERG) may be a crucial tool for clinicians to locate a window of opportunity in which degenerating yet viable RGCs could be rescued from irreversible damage. We suggest consideration of PERG as a tool in early retinal ganglion cell (RGC) dysfunction detection as well as for monitoring IOP lowering treatment. How to cite this article Tirsi A, Gliagias V, Sheha H, et al. Retinal Ganglion Cell Functional Recovery after Intraocular Pressure Lowering Treatment Using Prostaglandin Analogs in Glaucoma Suspects: A Prospective Pilot Study. J Curr Glaucoma Pract 2023;17(4):178-190.
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Affiliation(s)
- Andrew Tirsi
- Manhattan Eye, Ear and Throat Hospital; Donald and Barbara Zucker School of Medicine at Hofstra University/Northwell Health, Hempstead, New York, United States
| | - Vasiliki Gliagias
- Donald and Barbara Zucker School of Medicine at Hofstra University/Northwell Health, Hempstead, New York, United States
| | - Hosam Sheha
- Manhattan Eye, Ear and Throat Hospital; Donald and Barbara Zucker School of Medicine at Hofstra University/Northwell Health, Hempstead, New York, United States
| | - Bhakti Patel
- Donald and Barbara Zucker School of Medicine at Hofstra University/Northwell Health, Hempstead, New York, United States
| | - Julie Moehringer
- Sanford H. Calhoun High School, Merrick, New York, United States
| | - Joby Tsai
- Broward Health Medical Center, Fort Lauderdale, United States
| | - Rohun Gupta
- Donald and Barbara Zucker School of Medicine at Hofstra University/Northwell Health, Hempstead, New York, United States
| | - Stephen A Obstbaum
- Manhattan Eye, Ear and Throat Hospital; Donald and Barbara Zucker School of Medicine at Hofstra University/Northwell Health, Hempstead, New York, United States
| | - Celso Tello
- Manhattan Eye, Ear and Throat Hospital; Donald and Barbara Zucker School of Medicine at Hofstra University/Northwell Health, Hempstead, New York, United States
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Kim KH, Kim US. Efficacy of N95 amplitude of pattern electroretinogram measured from baseline to N95 trough in the traumatic optic neuropathy. Jpn J Ophthalmol 2019; 63:284-288. [PMID: 30848395 DOI: 10.1007/s10384-019-00664-9] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/20/2018] [Accepted: 01/27/2019] [Indexed: 10/27/2022]
Abstract
PURPOSE To investigate the utility of selected pattern electroretinogram (PERG) parameters-including N95 amplitude and N95/P50 ratio, and a BL-N95 amplitude-in the analysis of visual function(s) and for predicting changes in retinal ganglion cell structures in traumatic optic neuropathy. STUDY DESIGN A retrospective, observational case series performed at a single center. METHODS Forty-four eyes from 36 patients diagnosed with optic neuropathy were included. A BL-N95 amplitude was defined as the amplitude measured from baseline to the trough of N95. PERG and pattern visual evoked potential (pVEP) measures were acquired within 1 week after onset of optic neuropathies. To compare functional and anatomical changes, mean temporal peripapillary retinal nerve fiber layer (pRNFL) and average and minimum ganglion cell-inner plexiform layer (GC-IPL) thicknesses were measured using optical coherence tomography. RESULTS Thirty-six patients (20 men, 16 women; mean age 37.5 ± 17.6 years) were evaluated. The BL-N95 amplitude was significantly smaller than the N95 amplitude (1.01 ± 0.56 μV and 2.45 ± 1.02 μV, respectively; p < 0.0001). Both the N95 (r = - 0.38, p = 0.010) and BL-N95 r = - 0.32, p = 0.029) amplitudes were significantly correlated with visual acuity. Although P100 latency was not correlated with all PERG parameters, the N95 (r = 0.32, p = 0.032) and BL-N95 (r = 0.41, p = 0.005) amplitudes demonstrated a positive correlation with P100 amplitude in pVEP. PERG parameters, including the N95 and BL-N95 amplitudes, and N95/P50 ratio, were not correlated with pRNFL thickness in optical coherence tomography. Only the BL-N95 amplitude demonstrated a significant correlation with GC-IPL. CONCLUSION The BL-N95 amplitude-measured from baseline to the trough of N95-was valuable in the analysis of visual function(s) and for predicting changes in retinal ganglion cell structures in traumatic optic neuropathy.
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Affiliation(s)
- Kun Hae Kim
- Department of Ophthalmology, Kim's Eye Hospital, Youngshin-ro 136, Youngdeungpo-gu, Seoul, 07301, Korea
| | - Ungsoo Samuel Kim
- Department of Ophthalmology, Kim's Eye Hospital, Youngshin-ro 136, Youngdeungpo-gu, Seoul, 07301, Korea.
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Kurysheva NI, Maslova EV, Trubilina AV, Fomin AV, Lagutin MB. [Pattern electroretinogram and macular perfusion in glaucoma]. Vestn Oftalmol 2018; 134:34-40. [PMID: 30166508 DOI: 10.17116/oftalma201813404134] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/17/2022]
Abstract
PURPOSE To study microcirculatory and functional changes in macula in patients with Primary Open-Angle Glaucoma (POAG). MATERIAL AND METHODS The study included 95 POAG patients and 42 healthy control subjects. Whole en face image vessel density (wiVDRetina) was measured both in fovea and in parafovea using OCT-angiography (OCT-A) by means of SD-OCT AngioVue on Avanti RtVue xR (Optovue Inc., U.S.A.). Macular thickness and parameters of macular ganglion cell complex (GCC) were measured on the same day. Blood flow in the retrobulbar vessels was evaluated by means of Color Doppler Imaging (CDI). Pattern electroretinogram (PERG) was also taken from the study eyes. Correlations between PERG, SD-OCT GCC, macular thickness, and the parameters of OCT-A and CDI were studied. RESULTS The amplitude of t-PERG P50 decreased from 6.1±1.3 µV in normal eyes to 2.8±1.6 µV (p<0.0001) in early glaucoma and to 2.3±1.5 µV (p=0.93) in advanced stages. Relative vessel density of the capillary bed decreased from 51.3±3.0% in normal eyes to 45.9±5.0% (p<0.001) and to 41.8±5.0% (p=0.023) in early and advanced glaucoma respectively. The parameters of OCT-A and CDI correlated with morphological and functional parameters in normal and early glaucomatous eyes. CONCLUSION The study revealed reduction of macular microcirculation and decrease of PERG in early glaucoma. Correlations between the circulatory parameters and functional changes were found in early stages of the disease.
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Affiliation(s)
- N I Kurysheva
- Consultative-diagnostic Department of Ophthalmology Center of the Federal Medical and Biological Agency, Burnasyan Federal Medical Biophysical Center of FMBA, Department of Ophthalmology at Institute of Advanced Training of FMBA, 15 Gamalei St., Moscow, Russian Federation, 123098
| | - E V Maslova
- Consultative-diagnostic Department of Ophthalmology Center of the Federal Medical and Biological Agency, Burnasyan Federal Medical Biophysical Center of FMBA, Department of Ophthalmology at Institute of Advanced Training of FMBA, 15 Gamalei St., Moscow, Russian Federation, 123098
| | - A V Trubilina
- Consultative-diagnostic Department of Ophthalmology Center of the Federal Medical and Biological Agency, Burnasyan Federal Medical Biophysical Center of FMBA, Department of Ophthalmology at Institute of Advanced Training of FMBA, 15 Gamalei St., Moscow, Russian Federation, 123098
| | - A V Fomin
- Research Institute of Eye Diseases, 11A Rossolimo St., Moscow, Russian Federation, 119021
| | - M B Lagutin
- Lomonosov Moscow State University, Faculty of Mechanics and Mathematics, Department of Mathematical Statistics and Random Processes, GSP-1, Leninskie Gory, Moscow, Russian Federation, 119991
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Patangay S, Derafshi Z, Vajaranant TS, Park JC, Ghahari E, McAnany JJ, Hetling JR. Three Dimensional Stimulus Source for Pattern Electroretinography in Mid- and Far-peripheral Retina. Transl Vis Sci Technol 2018; 7:8. [PMID: 29367893 PMCID: PMC5777171 DOI: 10.1167/tvst.7.1.8] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/14/2017] [Accepted: 11/21/2017] [Indexed: 11/28/2022] Open
Abstract
PURPOSE The pattern electroretinogram (pERG) response reflects, in part, ganglion cell function. However, probing retinal ganglion cell (RGC) function in the mid- and far peripheral retina is difficult with conventional flat-panel pERG stimulus sources. A pattern stimulus source is presented for probing the peripheral retina. Peripheral pERG (ppERG) responses were evaluated versus luminance, reversal rate, and field subtended, and were compared with conventional pERG in healthy eyes. METHODS Eleven normally-sighted subjects were recruited. A hemispherical surface was used to present a reversing checkerboard pattern to the peripheral retina, from approximately 35° to 85° of visual field, in all directions. Responses to stimuli presented to peripheral field sectors (superior, nasal, inferior, temporal) were also recorded. Conventional pERG responses were recorded on the same day. Amplitudes and implicit times of waveform peaks were evaluated. RESULTS Robust pERG responses from peripheral retina resemble conventional pERG responses but with shorter implicit times and reduced positive component. Responses to high-luminance patterns include high-frequency components resembling flash ERG oscillatory potentials. Negative response component amplitudes increased with increasing pattern luminance, and decreased with increasing reversal rate. CONCLUSIONS Peripheral-field pERG responses are robust and repeatable; the unique response properties reflect differences between central and peripheral retina. Field-sector response ratios can be used to probe for sectoral dysfunction associated with disease. TRANSLATIONAL RELEVANCE The ppERG approach provides direct measurement of proximal retinal function beyond the fields probed by conventional perimetry and pERG, providing access to a relatively under studied part of the retina relevant to early stage glaucoma.
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Affiliation(s)
- Shresta Patangay
- Department of Bioengineering, University of Illinois at Chicago, Chicago, IL, USA
| | - Zahra Derafshi
- Department of Bioengineering, University of Illinois at Chicago, Chicago, IL, USA
| | - Thasarat S. Vajaranant
- Department of Ophthalmology and Visual Sciences, University of Illinois at Chicago, Chicago, IL, USA
| | - Jason C. Park
- Department of Ophthalmology and Visual Sciences, University of Illinois at Chicago, Chicago, IL, USA
| | - Elham Ghahari
- Department of Ophthalmology and Visual Sciences, University of Illinois at Chicago, Chicago, IL, USA
| | - J. Jason McAnany
- Department of Ophthalmology and Visual Sciences, University of Illinois at Chicago, Chicago, IL, USA
| | - John R. Hetling
- Department of Bioengineering, University of Illinois at Chicago, Chicago, IL, USA
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Abstract
The choroid is part of the uveal tract and is a heavily vascularized bed that also contains connective tissue and melanin pigment. Given the role of the choroidal vasculature in the blood supply of the anterior laminar and prelaminar regions of the optic nerve head, the peripapillary choroid might be a relevant target for investigation in patients with glaucoma. The purpose of this paper is to critically review the current understanding of potential role of the choroid in the pathogenesis of glaucomatous damage.
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Amarasekera DC, Resende AF, Waisbourd M, Puri S, Moster MR, Hark LA, Katz LJ, Fudemberg SJ, Mantravadi AV. Steady-state pattern electroretinogram and short-duration transient visual evoked potentials in glaucomatous and healthy eyes. Clin Exp Ophthalmol 2017; 46:54-61. [PMID: 28600806 DOI: 10.1111/ceo.13006] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/22/2016] [Revised: 05/22/2017] [Accepted: 05/23/2017] [Indexed: 11/28/2022]
Abstract
IMPORTANCE This study evaluates two rapid electrophysiological glaucoma diagnostic tests that may add a functional perspective to glaucoma diagnosis. BACKGROUND This study aimed to determine the ability of two office-based electrophysiological diagnostic tests, steady-state pattern electroretinogram and short-duration transient visual evoked potentials, to discern between glaucomatous and healthy eyes. DESIGN This is a cross-sectional study in a hospital setting. PARTICIPANTS Forty-one patients with glaucoma and 41 healthy volunteers participated in the study. METHODS Steady-state pattern electroretinogram and short-duration transient visual evoked potential testing was conducted in glaucomatous and healthy eyes. A 64-bar-size stimulus with both a low-contrast and high-contrast setting was used to compare steady-state pattern electroretinogram parameters in both groups. A low-contrast and high-contrast checkerboard stimulus was used to measure short-duration transient visual evoked potential parameters in both groups. MAIN OUTCOME MEASURES Steady-state pattern electroretinogram parameters compared were MagnitudeD, MagnitudeD/Magnitude ratio, and the signal-to-noise ratio. Short-duration transient visual evoked potential parameters compared were amplitude and latency. RESULTS MagnitudeD was significantly lower in glaucoma patients when using a low-contrast (P = 0.001) and high-contrast (P < 0.001) 64-bar-size steady-state pattern electroretinogram stimulus. MagnitudeD/Magnitude ratio and SNR were significantly lower in the glaucoma group when using a high-contrast 64-bar-size stimulus (P < 0.001 and P = 0.010, respectively). Short-duration transient visual evoked potential amplitude and latency were not significantly different between the two groups. CONCLUSIONS AND RELEVANCE Steady-state pattern electroretinogram was effectively able to discern between glaucomatous and healthy eyes. Steady-state pattern electroretinogram may thus have a role as a clinically useful electrophysiological diagnostic tool.
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Affiliation(s)
| | - Arthur F Resende
- Glaucoma Research Center, Wills Eye Hospital, Philadelphia, PA, USA
| | | | - Sanjeev Puri
- Glaucoma Research Center, Wills Eye Hospital, Philadelphia, PA, USA
| | - Marlene R Moster
- Glaucoma Research Center, Wills Eye Hospital, Philadelphia, PA, USA
| | - Lisa A Hark
- Glaucoma Research Center, Wills Eye Hospital, Philadelphia, PA, USA
| | - L Jay Katz
- Glaucoma Research Center, Wills Eye Hospital, Philadelphia, PA, USA
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Cvenkel B, Sustar M, Perovšek D. Ganglion cell loss in early glaucoma, as assessed by photopic negative response, pattern electroretinogram, and spectral-domain optical coherence tomography. Doc Ophthalmol 2017; 135:17-28. [DOI: 10.1007/s10633-017-9595-9] [Citation(s) in RCA: 30] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/06/2017] [Accepted: 05/25/2017] [Indexed: 10/19/2022]
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Tiryaki Demir S, Oba ME, Erdoğan ET, Odabaşı M, Dirim AB, Demir M, Can E, Kara O, Yekta Şendül S. Comparison of Pattern Electroretinography and Optical Coherence Tomography Parameters in Patients with Primary Open-Angle Glaucoma and Ocular Hypertension. Turk J Ophthalmol 2016; 45:229-234. [PMID: 27800239 PMCID: PMC5082259 DOI: 10.4274/tjo.39260] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/09/2014] [Accepted: 02/15/2015] [Indexed: 12/01/2022] Open
Abstract
Objectives: To investigate the correlation of visual field (VF), pattern electroretinography (PERG) and Fourier domain optical coherence tomography (FD-OCT) results in patients with ocular hypertension (OHT) and early primary open-angle glaucoma (POAG). Materials and Methods: The study included 72 eyes of 37 patients with early POAG, 76 eyes of 38 patients with OHT, and 60 eyes of 30 controls. All subjects underwent full ophthalmologic examination, VF assessment with 24-2 Humphrey standard automated perimetry (Swedish Interactive Thresholding Algorithm (SITA)-Standard), retinal nerve fiber layer (RNFL) and ganglion cell complex (GCC) thickness measurement with FD-OCT, and PERG P50 and N95 wave latency and amplitude measurements with electroretinography (Nihon Kohden). Results: With the exception of the nasal quadrant, all GCC parameters and RNFL results were significantly lower in the POAG group compared to the OHT and control groups. There was no statistically significant difference between the OHT and control group. PERG amplitudes were lower in the POAG and OHT groups than in the control group. Reduction in N95 amplitude was greater than that of P50 amplitude. No difference was detected in PERG latencies among groups. GCC was significantly correlated with VF and RNFL in the POAG group. Conclusion: Significant thinning of the GCC and RNFL occurs in addition to VF pathologies in patients with early POAG, and these examinations should be concomitantly evaluated. During diagnostic assessment of patients with early POAG, GCC and RNFL analysis by FD-OCT are highly effective. GCC is as reliable as RNLF in the early diagnosis of glaucoma and there is a highly significant correlation between them. Dysfunction of ganglion cells in patients with OHT may be detected earlier using PERG amplitude analysis.
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Affiliation(s)
- Semra Tiryaki Demir
- Şişli Etfal Training and Research Hospital, Clinic of Ophthalmology, İstanbul, Turkey
| | - Mehmet Ersin Oba
- Kafkas University Faculty of Medicine, Department of Ophthalmology, Kars, Turkey
| | - Ezgi Tuna Erdoğan
- İstanbul University İstanbul Faculty of Medicine, Department of Physiology, İstanbul, Turkey
| | - Mahmut Odabaşı
- Medipol University Faculty of Medicine, Department of Ophthalmology, İstanbul, Turkey
| | - Ayşe Burcu Dirim
- Şişli Etfal Training and Research Hospital, Clinic of Ophthalmology, İstanbul, Turkey
| | - Mehmet Demir
- Şişli Etfal Training and Research Hospital, Clinic of Ophthalmology, İstanbul, Turkey
| | - Efe Can
- Şişli Etfal Training and Research Hospital, Clinic of Ophthalmology, İstanbul, Turkey
| | - Orhan Kara
- Şişli Etfal Training and Research Hospital, Clinic of Ophthalmology, İstanbul, Turkey
| | - Selam Yekta Şendül
- Şişli Etfal Training and Research Hospital, Clinic of Ophthalmology, İstanbul, Turkey
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Predictive Value of HRT Stereometric Parameters and Blue-on-Yellow Perimetry Global Indices in Glaucoma-suspected Subjects. J Glaucoma 2016; 25:931-938. [PMID: 27782956 DOI: 10.1097/ijg.0000000000000444] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/27/2022]
Abstract
OBJECTIVE To determine subtle changes of Heidelberg retina tomography (HRT) stereometric parameters and blue-on-yellow (B/Y) perimetry global indices for the early diagnosis of glaucoma in suspected subjects. PATIENTS AND METHODS Cross-sectional data on 174 eyes of 87 subjects from a larger cohort, attending the Glaucoma Department of the "G. Gennimatas" General Hospital of Athens from January 2004 to February 2014, were used in the study. Subjects were assigned to 3 groups: (a) "normals" not requiring treatment throughout the study (group 1), (b) suspects who developed glaucoma and required treatment during the study (group 2), and (c) patients with incipient glaucoma (group 3). Specific HRT and B/Y perimetry variables were compared among the 3 groups. RESULTS Significant differences were established for the following HRT parameters: "reference height" differed significantly between groups 1 and 2 and groups 1 and 3; "cup shape measure" differed significantly between groups 1 and 2 and groups 2 and 3. B/Y perimetry global index "mean deviation" significantly distinguished group 2 from groups 1 and 3. CONCLUSIONS The results of the present study suggest the predictive value of the HRT stereometric parameters "reference height" and "cup shape measure" and of the B/Y perimetry global index "mean deviation" in glaucoma-suspected subjects; further corroboration through longitudinal studies is warranted.
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Can Variability of Pattern ERG Signal Help to Detect Retinal Ganglion Cells Dysfunction in Glaucomatous Eyes? BIOMED RESEARCH INTERNATIONAL 2015; 2015:571314. [PMID: 26167489 PMCID: PMC4475748 DOI: 10.1155/2015/571314] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 08/29/2014] [Revised: 12/30/2014] [Accepted: 01/01/2015] [Indexed: 11/29/2022]
Abstract
Objective. To evaluate variability of steady-state pattern electroretinogram (SS-PERG) signal in normal, suspected, and glaucomatous eyes. Methods. Twenty-one subjects with suspected glaucoma due to disc abnormalities (GS), 37 patients with early glaucoma (EG), and 24 normal control (NC) were tested with spectral-domain optical coherence tomography (SD-OCT), standard automated perimetry (SAP), and SS-PERG. Mean deviation (MD), pattern standard deviation (PSD), retinal nerve fiber layer (RNFL), and ganglionar complex cells (GCC) were evaluated. The SS-PERG was recorded five consecutive times and the amplitude and phase of second harmonic were measured. PERG amplitude and coefficient of variation of phase (CVphase) were recorded, and correlation with structural and functional parameters of disease, by means of one-way ANOVA and Pearson's correlation, was analysed. Results. PERG amplitude was reduced, as expression of retinal ganglion cells (RGCs) dysfunction, in EG patients and GS subjects compared to NC patients (P < 0.0001). CVphase was significantly increased in EG patients and GS subjects, compared to healthy (P < 0.0001), and it was also correlated with PSD (P = 0.0009), GCC (P = 0.028), and RNFL (P = 0.0078) only in EG patients. Conclusions. Increased intrasession variability of phase in suspected glaucomatous eyes may be a sign of RGCs dysfunction.
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Elbendary AM, Mohamed Helal R. Discriminating ability of spectral domain optical coherence tomography in different stages of glaucoma. Saudi J Ophthalmol 2013; 27:19-24. [PMID: 23964182 PMCID: PMC3729516 DOI: 10.1016/j.sjopt.2012.09.001] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/18/2012] [Revised: 07/07/2012] [Accepted: 09/30/2012] [Indexed: 11/21/2022] Open
Abstract
PURPOSE To determine the discriminating ability of retinal nerve fiber layer (RNFL) thickness measured with spectral-domain optical coherence tomography (SD-OCT) in different stages of glaucoma. PATIENTS AND METHODS Thirty normal, 150 glaucomatous eyes were included. Glaucomatous eyes were graded into early, moderate and severe stages according to one of the global indices called visual field index (VFI). Complete ophthalmic examination, white on white perimetry and SD-OCT were done for all patients. RNFL thickness of quadrants and average thickness were recorded. Area under receiver operating characteristic curves (AUCs) were used to assess the performance of OCT parameters. RESULTS AVERAGE, INFERIOR AND SUPERIOR RNFL THICKNESS WERE THE BEST PARAMETERS TO DISCRIMINATE NORMAL FROM EARLY GLAUCOMA (AUC: 0.91-86), early from moderate (AUC: 0.77-0.70) and moderate from severe (AUC: 0.85-83). Average RNFL loss was 18% in early glaucoma, 28% in moderate glaucoma and 41% in severe glaucoma. Early damage tends to be focal and in the lower quadrant. A significant correlation was detected between mean VFI and mean RNFL loss. Glaucoma was restaged according to average RNFL loss into early: ⩾97.5 μ, moderate: <97.5-72.5 μ and severe: <72.5 μ. CONCLUSION RNFL thickness measured with SD-OCT could discriminate the three stages of glaucoma. RNFL loss can be correlated to visual field loss. Future OCT-based staging of glaucoma, adjunctive to perimetry is possible.
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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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Demir HD, Inönü H, Kurt S, Doruk S, Aydın E, Etikan I. Evaluation of visual field parameters in patients with chronic obstructive pulmonary disease. Acta Ophthalmol 2012; 90:e349-54. [PMID: 22489568 DOI: 10.1111/j.1755-3768.2012.02432.x] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/26/2022]
Abstract
PURPOSE To evaluate the effects of chronic obstructive pulmonary disease (COPD) on retina and optic nerve. METHODS Thirty-eight patients with COPD and 29 healthy controls, totally 67 subjects, were included in the study. Visual evoked potentials (VEP) and visual field assessment (both standard achromatic perimetry (SAP) and short-wavelength automated perimetry (SWAP)) were performed on each subject after ophthalmological, neurological and pulmonary examinations. RESULTS Mean deviation (MD), pattern standard deviation (PSD) and corrected pattern standard deviation (CPSD) were significantly different between patient and control groups as for both SAP and SWAP measurements (p = 0.001, 0.019, 0.009 and p = 0.004,0.019, 0.031, respectively). Short-term fluctuation (SF) was not statistically different between the study and the control groups (p = 0.874 and 0.694, respectively). VEP P100 latencies were significantly different between patients with COPD and the controls (p = 0.019). CONCLUSION Chronic obstructive pulmonary disease is a systemic disease, and hypoxia in COPD seems to affect the retina and the optic nerve.
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Affiliation(s)
- Helin Deniz Demir
- Department of Ophthalmology, Gaziosmanpasa University School of Medicine, Tokat, Turkey.
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Gabelt BT, Rasmussen CA, Tektas OY, Kim CBY, Peterson JC, Nork TM, Ver Hoeve JN, Lütjen-Drecoll E, Kaufman PL. Structure/function studies and the effects of memantine in monkeys with experimental glaucoma. Invest Ophthalmol Vis Sci 2012; 53:2368-76. [PMID: 22427549 DOI: 10.1167/iovs.11-8475] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/24/2022] Open
Abstract
Purpose. The scanning laser polarimetry with variable corneal compensation (GDx VCC) methodology was established and verified in monkeys with experimental glaucoma (ExpG). Terminal GDx parameters were correlated with axon counts and electrophysiologic measures. The effects of memantine on these parameters were investigated. Methods. ExpG was induced in monkeys and intraocular pressure monitored weekly. Some monkeys received memantine in their diet before and after ExpG induction (1-10 months). GDx VCC scans, stereophotographs, and multifocal visual evoked potential (mfVEP) data were collected at baseline and every 6 to 8 weeks until euthanasia. Optic nerves were prepared for axon counting and other morphologic analysis. Results. There was no difference in IOP elevation exposure between memantine-treated and no-memantine-treated monkeys. The percentage of the optic nerve area composed of connective tissue septa was significantly greater in ExpG eyes than in Fellow eyes. There was a strong positive correlation between axon counts and terminal GDx parameter measures. Animals not receiving memantine exhibited significantly lower mfVEP amplitudes in ExpG eyes compared with the ipsilateral baseline or the final value in the Fellow eye. ExpG eyes from memantine-treated animals had higher overall mean amplitudes that were not significantly different relative to the ipsilateral baseline and final amplitudes in the Fellow eye. Conclusions. The authors' studies confirm that GDx VCC can be utilized in monkey ExpG studies to detect early retinal structural changes and that these changes are highly correlated with optic nerve axon counts. These structural changes may or may not lead to central functional changes as shown by the mfVEP in response to investigational therapies.
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Affiliation(s)
- B'ann T Gabelt
- Department of Ophthalmology and Visual Sciences, University of Wisconsin-Madison, Madison, Wisconsin 53705, USA
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Chang EE, Goldberg JL. Glaucoma 2.0: neuroprotection, neuroregeneration, neuroenhancement. Ophthalmology 2012; 119:979-86. [PMID: 22349567 DOI: 10.1016/j.ophtha.2011.11.003] [Citation(s) in RCA: 224] [Impact Index Per Article: 18.7] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/14/2011] [Revised: 11/02/2011] [Accepted: 11/02/2011] [Indexed: 01/15/2023] Open
Abstract
Glaucoma is a progressive neurodegenerative disease of retinal ganglion cells (RGCs) associated with characteristic axon degeneration in the optic nerve. Clinically, our only method of slowing glaucomatous loss of vision is to reduce intraocular pressure (IOP), but lowering IOP is only partially effective and does not address the underlying susceptibility of RGCs to degeneration. We review the recent steps forward in our understanding of the pathophysiology of glaucoma and discuss how this understanding has given us a next generation of therapeutic targets by which to maintain RGC survival, protect or rebuild RGC connections in the retina and brain, and enhance RGC function.
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Affiliation(s)
- Elma E Chang
- University of Miami Miller School of Medicine, Miami, FL, USA
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Bowd C, Tafreshi A, Zangwill LM, Medeiros FA, Sample PA, Weinreb RN. Pattern electroretinogram association with spectral domain-OCT structural measurements in glaucoma. Eye (Lond) 2010; 25:224-32. [PMID: 21183943 DOI: 10.1038/eye.2010.203] [Citation(s) in RCA: 26] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/27/2022] Open
Abstract
PURPOSE To describe the association between pattern electroretinogram (PERG) amplitude and spectral domain-optical coherence tomography (SD-OCT) macular thickness, retinal nerve fibre layer (RNFL) thickness and optic disc topography measurements. SUBJECTS AND METHODS Both eyes (n = 132) of 66 glaucoma patients (mean age = 67.9 years) enrolled in the University of California, San Diego, CA, USA, Diagnostic Innovations in Glaucoma Study (DIGS) were included. Eyes were tested with PERG (Glaid PERGLA, Lace Elettronica, Pisa, Italy), RTVue SD-OCT (Optovue Inc., Fremont, CA, USA) GCC, and NHM4 protocols on the same day. Of the 66 enrolled patients, 43 had glaucoma defined by repeated abnormal standard automated perimetry (SAP) results in at least one eye and 23 were glaucoma suspects defined by a glaucomatous-appearing optic disc by physicians' examination in at least one eye and normal SAP results in both eyes. Associations (R(2)) were determined between PERG amplitude (μV) and SD-OCT macular ganglion cell complex (GCC) thickness (μm), macular thickness (μm), macular outer retinal thickness (macular thickness minus GCC thickness) (μm), RNFL thickness (μm), neuroretinal rim area (mm(2)), and rim volume (mm(3)). RESULTS PERG amplitude was significantly associated with GCC thickness (R(2) = 0.179, P < 0.001), RNFL thickness (R(2) = 0.174, P < 0.001), and macular thickness (R(2) = 0.095, P<0.001). R(2) associations with other parameters were not significant (all P > 0.624). Significant associations remained for GCC and average RNFL thickness when age and intraocular pressure at the time of testing were included in multivariate models (both P ≤ 0.030). CONCLUSIONS PERG amplitude is significantly (but weakly) associated with macular GCC thickness, RNFL thickness, and macular thickness. The lack of association between PERG amplitude and macular outer retinal thickness supports previous results, possibly suggesting that that the PERG is driven primarily by retinal ganglion cell (inner retinal) responses.
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Affiliation(s)
- C Bowd
- Hamilton Glaucoma Center, Department of Ophthalmology, University of California, San Diego, La Jolla, CA 92037-0946, USA.
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Sehi M, Grewal DS, Goodkin ML, Greenfield DS. Reversal of retinal ganglion cell dysfunction after surgical reduction of intraocular pressure. Ophthalmology 2010; 117:2329-36. [PMID: 20920827 DOI: 10.1016/j.ophtha.2010.08.049] [Citation(s) in RCA: 61] [Impact Index Per Article: 4.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/04/2010] [Revised: 08/26/2010] [Accepted: 08/27/2010] [Indexed: 11/25/2022] Open
Abstract
PURPOSE The pattern electroretinogram optimized for glaucoma screening (PERGLA) is a noninvasive method of objectively measuring retinal ganglion cell (RGC) function. This study was undertaken to quantify the RGC response to intraocular pressure (IOP) reduction after glaucoma surgery. DESIGN Prospective cohort study. PARTICIPANTS Forty-seven eyes of 47 patients with uncontrolled IOP or progressive glaucomatous optic neuropathy receiving maximal medical therapy requiring trabeculectomy or aqueous drainage device implantation who met eligibility criteria. METHODS Eyes with visual acuity less than 20/30, corneal or retinal pathologic features, or unreliable standard automated perimetry (SAP) results were excluded. All patients underwent complete ocular examination, arterial blood pressure, SAP, and PERGLA at 2 sessions before surgery and at 3 months after surgery. Mean ocular perfusion pressure (MOPP) was calculated. Each measure of PERGLA amplitude and phase was an average of 600 artifact-free signal registrations. MAIN OUTCOME MEASURES Intraocular pressure and PERGLA amplitude and phase. RESULTS Forty-seven eyes of 47 patients (mean age ± standard deviation [SD], 69.9 ± 11.3 years) were enrolled. Thirty-four eyes (72%) underwent trabeculectomy with antifibrosis therapy; 13 eyes (28%) underwent glaucoma drainage implant surgery. Mean ± SD postoperative IOP (10.4 ± 4.6 mmHg) was significantly (P< 0.001) reduced compared with that before surgery (19.7 ± 8.6 mmHg). Mean ± SD postoperative PERGLA amplitude (0.46 ± 0.22 μV) was significantly (P = 0.001) increased compared with preoperative PERGLA amplitude (0.37 ± 0.18 μV). Mean ± SD postoperative PERGLA phase (1.72 ± 0.20 π-radian) was significantly (P = 0.01) reduced compared with preoperative PERGLA phase (1.81 ± 0.22 π-radian). Mean ± SD postoperative MOPP (53.1 ± 6.4 mmHg) was significantly (P < 0.001) increased compared with mean ± SD preoperative MOPP (45.8 ± 10.1 mmHg). No correlation (P > 0.05) was identified between change in PERGLA amplitude and change in IOP or MOPP. CONCLUSIONS Reversal of RGC dysfunction occurs after surgical reduction of IOP and may be quantified using PERGLA.
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Affiliation(s)
- Mitra Sehi
- Bascom Palmer Eye Institute, Department of Ophthalmology, University of Miami Miller School of Medicine, Palm Beach Gardens, Florida 33418, USA.
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Sehi M, Grewal DS, Feuer WJ, Greenfield DS. The impact of intraocular pressure reduction on retinal ganglion cell function measured using pattern electroretinogram in eyes receiving latanoprost 0.005% versus placebo. Vision Res 2010; 51:235-42. [PMID: 20813123 DOI: 10.1016/j.visres.2010.08.036] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/04/2010] [Revised: 08/23/2010] [Accepted: 08/26/2010] [Indexed: 10/19/2022]
Abstract
PURPOSE To evaluate the impact of intraocular (IOP) reduction on retinal ganglion cell (RGC) function measured using pattern electroretinogram optimized for glaucoma (PERGLA) in glaucoma suspect and glaucomatous eyes receiving latanoprost 0.005% versus placebo. METHODS This was a prospective, placebo-controlled, double masked, cross-over clinical trial. One randomly selected eye of each subject meeting eligibility criteria was enrolled. At each visit, subjects underwent five diurnal measurements between 8:00 am and 4:00 pm consisting of Goldmann IOP, and PERGLA measurements. A baseline examination was performed following a 4-week washout period, and repeat examination after randomly receiving latanoprost or placebo for 4-weeks. Subjects were then crossed over to receive the alternative therapy for 4 weeks following a second washout period, and underwent repeat examination. Linear mixed-effect models were used for the analysis. RESULTS Sixty-eight eyes (35 glaucoma, 33 glaucoma suspect) of 68 patients (mean age 67.4 ± 10.6 years) were enrolled. The mean IOP (mmHg) after latanoprost 0.005% therapy (14.9 ± 3.8) was significantly lower than baseline (18.8 ± 4.7, p<0.001) or placebo (18.0 ± 4.3), with a mean reduction of -20 ± 13%. Mean PERGLA amplitude (μV) and phase (π-radian) using latanoprost (0.49 ± 0.22 and 1.71 ± 0.22, respectively) were similar (p > 0.05) to baseline (0.49 ± 0.24 and 1.69 ± 0.19) and placebo (0.50 ± 0.24 and 1.72 ± 0.23). No significant (p > 0.05) diurnal variation in PERGLA amplitude was observed at baseline, or using latanoprost or placebo. Treatment with latanoprost, time of day, and IOP were not significantly (p > 0.05) associated with PERGLA amplitude or phase. CONCLUSION Twenty percent IOP reduction using latanoprost monotherapy is not associated with improvement in RGC function measured with PERGLA.
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Affiliation(s)
- Mitra Sehi
- Department of Ophthalmology, Bascom Palmer Eye Institute, University of Miami Miller School of Medicine, Palm Beach Gardens, FL 33418, USA
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