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Marmoy OR, Tekavčič Pompe M, Kremers J. Chromatic visual evoked potentials: A review of physiology, methods and clinical applications. Prog Retin Eye Res 2024; 101:101272. [PMID: 38761874 DOI: 10.1016/j.preteyeres.2024.101272] [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: 07/20/2023] [Revised: 05/06/2024] [Accepted: 05/10/2024] [Indexed: 05/20/2024]
Abstract
Objective assessment of the visual system can be performed electrophysiologically using the visual evoked potential (VEP). In many clinical circumstances, this is performed using high contrast achromatic patterns or diffuse flash stimuli. These methods are clinically valuable but they may only assess a subset of possible physiological circuitries within the visual system, particularly those involved in achromatic (luminance) processing. The use of chromatic VEPs (cVEPs) in addition to standard VEPs can inform us of the function or dysfunction of chromatic pathways. The chromatic VEP has been well studied in human health and disease. Yet, to date our knowledge of their underlying mechanisms and applications remains limited. This likely reflects a heterogeneity in the methodology, analysis and conclusions of different works, which leads to ambiguity in their clinical use. This review sought to identify the primary methodologies employed for recording cVEPs. Furthermore cVEP maturation and application in understanding the function of the chromatic system under healthy and diseased conditions are reviewed. We first briefly describe the physiology of normal colour vision, before describing the methodologies and historical developments which have led to our understanding of cVEPs. We thereafter describe the expected maturation of the cVEP, followed by reviewing their application in several disorders: congenital colour vision deficiencies, retinal disease, glaucoma, optic nerve and neurological disorders, diabetes, amblyopia and dyslexia. We finalise the review with recommendations for testing and future directions.
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Affiliation(s)
- Oliver R Marmoy
- Clinical and Academic Department of Ophthalmology, Great Ormond Street Hospital for Children, London, UK; UCL-GOS Institute of Child Health, University College London, London, UK.
| | - Manca Tekavčič Pompe
- University Eye Clinic, University Medical Centre Ljubljana, Ljubljana, Slovenia; Faculty of Medicine, University of Ljubljana, Slovenia
| | - Jan Kremers
- Section of Retinal Physiology, University Hospital Erlangen, Germany
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Li J, Wang Y, Xie X, Zeng W, Li S, Agrawal R, Feng Y. Bilateral Pattern Electroretinogram Abnormalities in Patients with Herpes Zoster Keratitis and Conjunctivitis. Ophthalmol Ther 2024; 13:1589-1599. [PMID: 38587772 PMCID: PMC11109080 DOI: 10.1007/s40123-024-00928-9] [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: 01/11/2024] [Accepted: 03/05/2024] [Indexed: 04/09/2024] Open
Abstract
INTRODUCTION Herpes zoster ophthalmicus (HZO) results from the reactivation of varicella zoster virus (VZV) in the ophthalmic branch of the trigeminal nerve. The inflammation caused by VZV involves multiple tissues in the eyes. Our goal is to evaluate pattern electroretinogram (PERG) changes and their relationship with corneal sub-basal nerve changes in patients with HZO. METHODS Twenty-two patients with herpes zoster keratitis or conjunctivitis and 20 healthy volunteers were recruited for this cross-sectional study. A PERG test was performed on both eyes of HZO patients and one eye of the healthy controls. In vivo confocal microscopy (IVCM) was also performed on both eyes of the HZO patients to detect corneal nerve damage. RESULTS Our results showed changes in the PERG parameters in both eyes of HZO patients compared to the healthy controls. Affected eyes showed delayed N95 peak time and decreased P50 and N95 amplitude compared to the unaffected eyes (p < 0.05, respectively). Both affected and unaffected eyes in HZO patients showed delayed P50 peak time and decreased N95 amplitude (p < 0.05, respectively) compared to controls. In HZO patients, no significant differences in each PERG parameter were found between eyes with and without corneal lesions or between eyes with and without increased Langham's cells in the corneal epithelial sub-basal layer. The IVCM images showed decreased total nerve length and number at the sub-basal layer of the epithelial cornea in affected eyes compared to unaffected eyes (p < 0.05). No significant correlation was found between total nerve length and PERG changes. CONCLUSIONS Our results showed that VZV-affected eyes without central cornea involvement displayed reduced N95 amplitude and prolonged P50 peak time in bilateral eyes compared to the healthy controls. Larger studies are needed to further explore the effect of HZO on the electrophysiological response of the eye and the posterior segment.
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Affiliation(s)
- Jingyi Li
- Department of Ophthalmology, Peking University Third Hospital, No. 49, North Garden Street, Haidian District, Beijing, China
| | - Yuexin Wang
- Department of Ophthalmology, Peking University Third Hospital, No. 49, North Garden Street, Haidian District, Beijing, China
| | - Xin Xie
- Department of Ophthalmology, Peking University Third Hospital, No. 49, North Garden Street, Haidian District, Beijing, China
| | - Weizhen Zeng
- Department of Ophthalmology, Peking University Third Hospital, No. 49, North Garden Street, Haidian District, Beijing, China
| | - Shiying Li
- Department of Ophthalmology, Xiang'an Hospital of Xiamen University, No. 2000, Xiang'an East Road, Xiang'an District, Xiamen, Fujian, China.
- Eye Institute of Xiamen University, Xiamen, China.
| | - Rupesh Agrawal
- National Healthcare Group Eye Institute, Tan Tock Seng Hospital, Singapore, Singapore
- Lee Kong Chian School of Medicine, Nanyang Technological University, Singapore, Singapore
- Singapore Eye Research Institute, Singapore, Singapore
| | - Yun Feng
- Department of Ophthalmology, Peking University Third Hospital, No. 49, North Garden Street, Haidian District, Beijing, China.
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Friedel EBN, Tebartz van Elst L, Beringer M, Endres D, Runge K, Maier S, Kornmeier J, Bach M, Domschke K, Heinrich SP, Nickel K. Reduced contrast sensitivity, pattern electroretinogram ratio, and diminished a-wave amplitude in patients with major depressive disorder. Eur Arch Psychiatry Clin Neurosci 2024:10.1007/s00406-024-01826-8. [PMID: 38805071 DOI: 10.1007/s00406-024-01826-8] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 03/15/2024] [Accepted: 05/10/2024] [Indexed: 05/29/2024]
Abstract
The electroretinogram (ERG), a non-invasive electrophysiological tool used in ophthalmology, is increasingly applied to investigate neural correlates of depression. The present study aimed to reconsider previous findings in major depressive disorder (MDD) reporting (1) a diminished contrast sensitivity and (2) a reduced patten ERG (PERG) amplitude ratio, and additionally, to assess (3) the photopic negative response (PhNR) from the flash ERG (fERG), with the RETeval® device, a more practical option for clinical routine use. We examined 30 patients with a MDD and 42 healthy controls (HC), assessing individual contrast sensitivity thresholds with an optotype-based contrast test. Moreover, we compared the PERG ratio, an established method for early glaucoma detection, between both groups. The handheld ERG device was used to measure amplitudes and peak times of the fERG components including a-wave, b-wave and PhNR in both MDD patients and HCs. MDD patients exhibited diminished contrast sensitivity together with a reduced PERG ratio, compared to HC. With the handheld ERG device, we found reduced a-wave amplitudes in MDD, whereas no significant differences were observed in the fERG b-wave or PhNR between patients and controls. The reduced contrast sensitivity and PERG ratio in MDD patients supports the hypothesis that depression is associated with altered visual processing. The findings underscore the PERG's potential as a possible objective marker for depression. The reduced a-wave amplitude recorded with the RETeval® system in MDD patients might open new avenues for using handheld ERG devices as simplified approaches for advancing depression research compared to the PERG.
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Affiliation(s)
- Evelyn B N Friedel
- Department of Psychiatry and Psychotherapy, Medical Center - University of Freiburg, Faculty of Medicine, University of Freiburg, Freiburg, Germany
- Eye Center, Medical Center - University of Freiburg, Faculty of Medicine, University of Freiburg, Freiburg, Germany
- Faculty of Biology, University of Freiburg, Freiburg, Germany
| | - Ludger Tebartz van Elst
- Department of Psychiatry and Psychotherapy, Medical Center - University of Freiburg, Faculty of Medicine, University of Freiburg, Freiburg, Germany
| | - Malina Beringer
- Department of Psychiatry and Psychotherapy, Medical Center - University of Freiburg, Faculty of Medicine, University of Freiburg, Freiburg, Germany
| | - Dominique Endres
- Department of Psychiatry and Psychotherapy, Medical Center - University of Freiburg, Faculty of Medicine, University of Freiburg, Freiburg, Germany
| | - Kimon Runge
- Department of Psychiatry and Psychotherapy, Medical Center - University of Freiburg, Faculty of Medicine, University of Freiburg, Freiburg, Germany
| | - Simon Maier
- Department of Psychiatry and Psychotherapy, Medical Center - University of Freiburg, Faculty of Medicine, University of Freiburg, Freiburg, Germany
| | - Jürgen Kornmeier
- Department of Psychiatry and Psychotherapy, Medical Center - University of Freiburg, Faculty of Medicine, University of Freiburg, Freiburg, Germany
- Faculty of Biology, University of Freiburg, Freiburg, Germany
- Institute for Frontier Areas of Psychology and Mental Health, Freiburg, Germany
| | - Michael Bach
- Eye Center, Medical Center - University of Freiburg, Faculty of Medicine, University of Freiburg, Freiburg, Germany
| | - Katharina Domschke
- Department of Psychiatry and Psychotherapy, Medical Center - University of Freiburg, Faculty of Medicine, University of Freiburg, Freiburg, Germany
- German Center for Mental Health (DZPG), Partner Site Berlin, Berlin, Germany
| | - Sven P Heinrich
- Eye Center, Medical Center - University of Freiburg, Faculty of Medicine, University of Freiburg, Freiburg, Germany
| | - Kathrin Nickel
- Department of Psychiatry and Psychotherapy, Medical Center - University of Freiburg, Faculty of Medicine, University of Freiburg, Freiburg, Germany.
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Sustar Habjan M, Cvenkel B. Slope between positive and negative ERG components in patients with open-angle glaucoma. Doc Ophthalmol 2024:10.1007/s10633-024-09972-z. [PMID: 38605262 DOI: 10.1007/s10633-024-09972-z] [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: 09/28/2023] [Accepted: 03/21/2024] [Indexed: 04/13/2024]
Abstract
PURPOSE To evaluate ERG morphology, in particular the slope between P50 and N95 components of the PERG, as well as between the b-wave and the photopic negative response (PhNR) of the light-adapted (LA) ERG in patients with retinal ganglion cell (RGC) dysfunction due to open-angle glaucoma. METHODS The PERG and LA-ERG traces of 16 glaucoma patients and 21 age-similar controls were retrospectively analysed. The ERG signal between the peak of the positive component (P50 and b-wave) towards the negative component (N95 and PhNR) was described by a linear regression y = a + bx, where the parameter b indicated the steepness of the P50-N95 and b-PhNR slope. RESULTS The P50-N95 slope was less steep in glaucoma patients (-0.079 ± 0.034 vs. -0.166 ± 0.050 in controls, p < 0.001), while the b-PhNR slope was not affected (-4.2 ± 2.1 vs. -4.4 ± 1.2, p = NS). The P50-N95 slope showed strong correlation with PhNR and N95 amplitude (r = -0.68 and -0.92, respectively; p < 0.001), while the b-PhNR slope correlated only with b-wave amplitude (r = -0.66, p < 0.001). CONCLUSIONS The P50-N95 slope is a sensitive indicator of RGC dysfunction in patients with open-angle glaucoma. A similar component of LA-ERG, the b-PhNR slope, is less affected by glaucomatous RGC dysfunction and probably originates from similar retinal mechanisms as the b-wave.
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Affiliation(s)
- Maja Sustar Habjan
- Department of Ophthalmology, University Medical Centre Ljubljana, Grabloviceva 46, 1000, Ljubljana, Slovenia.
| | - Barbara Cvenkel
- Department of Ophthalmology, University Medical Centre Ljubljana, Grabloviceva 46, 1000, Ljubljana, Slovenia
- Faculty of Medicine, University of Ljubljana, 1000, Ljubljana, Slovenia
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Friedel EBN, Haldina J, Nickel K, Bach M, Tebartz van Elst L, Heinrich SP. Effect of eccentric fixation on the steady-state pattern electroretinogram. Doc Ophthalmol 2024; 148:87-95. [PMID: 38416305 PMCID: PMC10954955 DOI: 10.1007/s10633-024-09967-w] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/05/2023] [Accepted: 01/20/2024] [Indexed: 02/29/2024]
Abstract
PURPOSE The steady-state pattern electroretinogram (ssPERG) is used to assess retinal ganglion cell function in a variety of research contexts and diagnostic applications. In certain groups of patients or study participants, stable central fixation of the stimulus is not guaranteed. The present study aimed at assessing the effects of misfixation on the ssPERG response to checkerboard reversal stimuli. METHODS Using two check sizes (0.8° and 15°), we compared ssPERG responses for several amounts of fixation deviation, ranging from 0° to 19° horizontally and from 0° to 14° diagonally. The stimulus area extended to 15° eccentricity, stimulus reversal rate was 15/s. RESULTS Up to around 7° eccentricity, there was no sizable effect of fixation deviation under most conditions. Effects were somewhat larger for nasal than for temporal deviation, in particular for small checks. Diagonal deviation was associated with a response to luminance onset/offset at 7.5 Hz (subharmonic of the reversal rate), most prominently when the interior of a large check was fixated. CONCLUSION Generally, moderate inaccuracies of fixation do not have a sizable effect on ssPERG amplitude. However, with large checks, the luminance response has to be considered.
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Affiliation(s)
- Evelyn B N Friedel
- Eye Center, Medical Center - University of Freiburg, Faculty of Medicine, University of Freiburg, Freiburg, Germany.
- Department of Psychiatry and Psychotherapy, Medical Center - University of Freiburg, Faculty of Medicine, University of Freiburg, Freiburg, Germany.
- Faculty of Biology, University of Freiburg, Freiburg, Germany.
| | - Julia Haldina
- Eye Center, Medical Center - University of Freiburg, Faculty of Medicine, University of Freiburg, Freiburg, Germany
| | - Kathrin Nickel
- Department of Psychiatry and Psychotherapy, Medical Center - University of Freiburg, Faculty of Medicine, University of Freiburg, Freiburg, Germany
| | - Michael Bach
- Eye Center, Medical Center - University of Freiburg, Faculty of Medicine, University of Freiburg, Freiburg, Germany
| | - Ludger Tebartz van Elst
- Department of Psychiatry and Psychotherapy, Medical Center - University of Freiburg, Faculty of Medicine, University of Freiburg, Freiburg, Germany
| | - Sven P Heinrich
- Eye Center, Medical Center - University of Freiburg, Faculty of Medicine, University of Freiburg, Freiburg, Germany
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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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Ahn EJ, Shin YI, Kim YK, Jeoung JW, Park KH. Hemifield-based analysis of pattern electroretinography in normal subjects and patients with preperimetric glaucoma. Sci Rep 2024; 14:5116. [PMID: 38429373 PMCID: PMC10907379 DOI: 10.1038/s41598-024-55601-9] [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: 12/11/2023] [Accepted: 02/26/2024] [Indexed: 03/03/2024] Open
Abstract
This prospective cross-sectional study investigated the visual function of preperimetric glaucoma (PPG) patients based on hemifield (HF) pattern electroretinogram (PERG) amplitudes. Thirty-two (32) normal subjects and 33 PPG patients were enrolled in control and PPG groups, respectively. All of the participants had undergone full ophthalmic examinations, including spectral-domain optical coherence tomography (SD-OCT), visual field (VF) examination and pattern electroretinography (PERG). The PERG parameters along with the HF ratios of SD-OCT and PERG were compared between the control and PPG groups. Pairwise Pearson's correlation coefficients and linear regression models were fitted to investigate the correlations. The PERG N95 amplitudes were significantly lower in the PPG group (P < 0.001). The smaller/larger HF N95 amplitude ratio of the PPG group was found to be smaller than that of the control group (0.73 ± 0.20 vs. 0.86 ± 0.12; P = 0.003) and showed positive correlations with affected HF average ganglion cell-inner plexiform layer (GCIPL) thickness (r = 0.377, P = 0.034) and with average GCIPL thickness (r = 0.341, P = 0.005). The smaller/larger HF N95 amplitude ratio did not significantly change with age (β = - 0.005, P = 0.195), whereas the full-field N95 amplitude showed a negative correlation with age (β = - 0.081, P < 0.001). HF analysis of PERG N95 amplitudes might be particularly useful for patients with early glaucoma.
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Affiliation(s)
- Eun Jung Ahn
- Department of Ophthalmology, Seoul National University College of Medicine, Seoul, Korea
- Daehakro Seoul Eye Clinic, Seoul, Korea
| | - Young In Shin
- Department of Ophthalmology, Seoul National University College of Medicine, Seoul, Korea
- Department of Ophthalmology, Gachon University Gil Hospital, Incheon, Korea
| | - Young Kook Kim
- Department of Ophthalmology, Seoul National University College of Medicine, Seoul, Korea
- Department of Ophthalmology, Seoul National University Hospital, Seoul, Korea
| | - Jin Wook Jeoung
- Department of Ophthalmology, Seoul National University College of Medicine, Seoul, Korea
- Department of Ophthalmology, Seoul National University Hospital, Seoul, Korea
| | - Ki Ho Park
- Department of Ophthalmology, Seoul National University College of Medicine, Seoul, Korea.
- Department of Ophthalmology, Seoul National University Hospital, Seoul, Korea.
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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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Alhagaa AA, Mahmoud Badawi N, Abd Allah El-Morsy O. Primary Open Angle Glaucoma Diagnosis Using Pattern Electroretinogram Parameters. Clin Ophthalmol 2023; 17:3281-3293. [PMID: 37933330 PMCID: PMC10625753 DOI: 10.2147/opth.s424323] [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: 08/13/2023] [Accepted: 10/19/2023] [Indexed: 11/08/2023] Open
Abstract
Background Glaucoma is the most typical cause of permanent blindness. POAG, or primary open angle glaucoma, is the most common type. The pattern electroretinogram (PERG) has become a promising technique for detecting glaucoma early-on. The goal of this study was to assess the ability of PERG to diagnose POAG, especially in early, difficult-to-diagnose cases in comparison with other already established diagnostic methods. Methods 150 participants (300 eyes) were enrolled in a cross-sectional study at ophthalmology department at Menoufia University Hospital in August 2022 to February 2023. All recruited participants underwent comprehensive ophthalmological and PERG exams. The studied eyes were divided into three groups as 100 normal eyes (Group I), 100 eyes with preperimetric glaucoma (Group II), and 100 eyes with established perimetric glaucoma (Group III). Results OCT-RNFL average thickness had a significant positive correlation with P50 latency (r=0.289, p=0.041) or P50 amplitude (r=0.302, p=0.018) and N95 amplitude (r=0.640, p=0.001) among group (II). Also, RNFL thickness had negative correlation with P50 amplitude (r= -0.268, p=0.043) among group (III). RNFL thickness and P50 and N95 amplitude showed highest AUC values in detecting preperimetric glaucomatous eyes vs normal eyes (AUC=0.927, 0.952, 904), and for detecting established perimetric glaucomatous eyes vs normal eyes (AUC=1.00, 0.957, 0.983 respectively) compared with VF MD which showed AUC (0.458 and 0.901 respectively). Conclusion Glaucoma patients exhibit PERG alterations (comparable to RNFL thickness changes) so, it could be used as an accurate diagnostic method in POAG. Because PERG alterations occur before visual field abnormalities, it could be relied on as an early diagnostic tool in preperimetric glaucoma. We can use both RNFL thickness assessment by OCT with PERG parameters as complementary tests for accurate diagnosis of preperimetric glaucoma which represents the most difficult diagnostic challenge in glaucoma diagnosis.
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Affiliation(s)
- Ahmed A Alhagaa
- Ophthalmology Department, Faculty of Medicine, Menoufia University, Shebin Elkom, Menoufia, 6132415, Egypt
| | - Nermeen Mahmoud Badawi
- Ophthalmology Department, Faculty of Medicine, Menoufia University, Shebin Elkom, Menoufia, 6132415, Egypt
| | - Osama Abd Allah El-Morsy
- Ophthalmology Department, Faculty of Medicine, Menoufia University, Shebin Elkom, Menoufia, 6132415, Egypt
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Dunn M, Cull G, Reynaud J, Jennings D, Holthausen T, Di Polo A, Fortune B. Utility of Light-Adapted Full-Field Electroretinogram ON and OFF Responses for Detecting Glaucomatous Functional Damage. Transl Vis Sci Technol 2023; 12:16. [PMID: 37594448 PMCID: PMC10445177 DOI: 10.1167/tvst.12.8.16] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/19/2022] [Accepted: 07/13/2023] [Indexed: 08/19/2023] Open
Abstract
Purpose To compare parameters of electroretinogram (ERG) responses for their ability to detect functional loss in early stages of nonhuman primate (NHP) experimental glaucoma (EG), including photopic negative responses (PhNR) to a standard brief red flash on a blue background (R/B) and 200-ms-long R/B and white-on-white (W/W) flashes, to W/W flicker stimuli (5-50 Hz), and to a dark-adapted intensity series. Methods Light-adapted ERGs were recorded in 12 anesthetized monkeys with unilateral EG. Amplitudes and implicit times of the a-wave, b-wave, and d-wave were measured, as well as amplitudes of PhNRs and oscillatory potentials for flash onset and offset. Flicker ERGs were measured using peak-trough and fundamental frequency analyses. Dark-adapted ERG parameters were modeled by Naka-Rushton relationships. Results Only PhNR amplitudes were significantly reduced in EG eyes compared to fellow control (FC) eyes. The d-wave implicit time was delayed in EG versus FC eyes only for the W/W long flash, but in all eyes it was 10 to 20 ms slower for R/B versus the W/W condition. Flicker ERGs were <0.5 ms delayed in EG versus FC overall, but amplitudes were affected only at 5 Hz. The brief R/B PhNR amplitude had the highest sensitivity to detect EG and strongest correlation to parameters of structural damage. Conclusions The PhNR to the standard brief R/B stimulus was best for detecting and following early-stage functional loss in NHP EG. Translational Relevance These results suggest that there would be no benefit in using longer duration flashes to separate onset and offset responses for clinical management of glaucoma.
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Affiliation(s)
- Michaela Dunn
- Discoveries in Sight Research Laboratories, Devers Eye Institute, Legacy Health, Portland, OR, USA
| | - Grant Cull
- Discoveries in Sight Research Laboratories, Devers Eye Institute, Legacy Health, Portland, OR, USA
| | - Juan Reynaud
- Discoveries in Sight Research Laboratories, Devers Eye Institute, Legacy Health, Portland, OR, USA
| | - Dawn Jennings
- Discoveries in Sight Research Laboratories, Devers Eye Institute, Legacy Health, Portland, OR, USA
| | - Trinity Holthausen
- Discoveries in Sight Research Laboratories, Devers Eye Institute, Legacy Health, Portland, OR, USA
| | - Adriana Di Polo
- Department of Neuroscience, Université de Montréal, Montréal, QC, Canada
- Neuroscience Division, Centre de Recherche du Centre Hospitalier, Université de Montréal, Montréal, QC, Canada
| | - Brad Fortune
- Discoveries in Sight Research Laboratories, Devers Eye Institute, Legacy Health, Portland, OR, USA
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11
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Liu S, Yuan F, Xiang M. Comparative analysis of electroretinogram with subdermal and invasive recording methods in mice. Biochem Biophys Res Commun 2023; 655:118-126. [PMID: 36934587 DOI: 10.1016/j.bbrc.2023.03.029] [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: 02/24/2023] [Accepted: 03/10/2023] [Indexed: 03/12/2023]
Abstract
Electroretinogram (ERG) is the most common clinical and basic visual electrodiagnostic test, which has long been used to evaluate the retinal function through photic stimulation. Despite its wide application, there are still some pitfalls often neglected in ERG recording, such as the recording time point, active electrode location, and the animal strain. In this study, we systematically analyzed and compared the effects of multiple factors on ERG, which would provide an important reference for ERG detection by other investigators. ERG was recorded using the Celeris D430 rodent ERG testing system. The amplitudes and latencies of a wave, b wave and oscillatory potentials (OPs) recorded from different electrode locations (subdermal and invasive), different times of day (day time 8:00 to 13:00 and night time 18:00 to 23:00), bilateral eyes (left and right), and different mouse strains (C57 and CD1) were analyzed and compared. Our results revealed that ERG was affected by active electrode locations and difference between day and night, while OPs seemed not to be influenced. There was no significant difference in the amplitudes or latencies of ERG and OPs between left and right eyes, irrespective of measurements at day or night, or which method was used. Compared to C57 mice, both ERG and OP responses were significantly decreased in Brn3bAP/AP mice, a model for retinal ganglion cell (RGC) loss. In addition, there were some non-negligible differences in visual responses between C57 and CD1 mouse strains. Our results suggest that the invasive procedure is a reliable method for evaluating the visual function including VEP, ERG and OP responses in mice. Moreover, these comparative analyses provide valuable references for future studies of mammalian visual electrophysiology.
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Affiliation(s)
- Shuting Liu
- State Key Laboratory of Ophthalmology, Zhongshan Ophthalmic Center, Sun Yat-sen University, Guangdong Provincial Key Laboratory of Ophthalmology and Visual Science, Guangzhou, 510060, China
| | - Fa Yuan
- State Key Laboratory of Ophthalmology, Zhongshan Ophthalmic Center, Sun Yat-sen University, Guangdong Provincial Key Laboratory of Ophthalmology and Visual Science, Guangzhou, 510060, China
| | - Mengqing Xiang
- State Key Laboratory of Ophthalmology, Zhongshan Ophthalmic Center, Sun Yat-sen University, Guangdong Provincial Key Laboratory of Ophthalmology and Visual Science, Guangzhou, 510060, China; Guangdong Provincial Key Laboratory of Brain Function and Disease, Zhongshan School of Medicine, Sun Yat-sen University, Guangzhou, 510080, China.
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12
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Lauwers A, Barbosa Breda J, Stalmans I. The natural history of untreated ocular hypertension and glaucoma. Surv Ophthalmol 2022; 68:388-424. [PMID: 36563707 DOI: 10.1016/j.survophthal.2022.12.001] [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: 09/10/2022] [Revised: 12/07/2022] [Accepted: 12/12/2022] [Indexed: 12/25/2022]
Abstract
Glaucoma is a chronic, progressive disease leading to irreversible blindness if left untreated; however, since reducing intraocular pressure has proven to be successful in slowing disease progression, little is known about the natural history of untreated glaucoma. This knowledge can be valuable in guiding management decisions in the era of personalized medicine. A systematic search was performed in Medline (PubMed), Embase, and Web of Science in accordance with the Preferred Reporting Items for Systematic reviews and Meta-Analyses (PRIMSA) guidelines. The rate of structural and/or functional progression and conversion to glaucoma or to a more advanced stage of glaucoma are discussed for ocular hypertension and different types of open-angle glaucoma. Forty-three studies were included. Different rates of progression were found both among and within the different diagnostic groups that belong to the open-angle glaucoma spectrum. The highest rate was found in pseudoexfoliation glaucoma, followed by high tension glaucoma, normal tension glaucoma, and ocular hypertension, in decreasing order. The lowest rate was observed in glaucoma suspects. The known rates of progression provide valuable prognostic information for ophthalmologists and patients. Nonetheless, due to high variability among patients, individual progression cannot be accurately predicted and repeated follow-up examinations are required to estimate individual progression.
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Affiliation(s)
- Amelien Lauwers
- Department of Ophthalmology, Faculty of Medicine, University Hospitals Leuven, 3000 Leuven, Belgium
| | - João Barbosa Breda
- Research Group Ophthalmology, Department of Neurosciences, KU Leuven, 3000 Leuven, Belgium; Department of Ophthalmology, Centro Hospitalar e Universitário São João, 4200-319 Porto, Portugal; Cardiovascular R&D Centre - UnIC@RISE, Department of Surgery and Physiology, Faculty of Medicine of the University of Porto, 4200-319 Porto, Portugal.
| | - Ingeborg Stalmans
- Research Group Ophthalmology, Department of Neurosciences, KU Leuven, 3000 Leuven, Belgium; Department of Ophthalmology, University Hospitals Leuven, 3000 Leuven, Belgium
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13
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Phenotype Characterization of a Mice Genetic Model of Absolute Blindness. Int J Mol Sci 2022; 23:ijms23158152. [PMID: 35897728 PMCID: PMC9331777 DOI: 10.3390/ijms23158152] [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: 06/23/2022] [Revised: 07/19/2022] [Accepted: 07/22/2022] [Indexed: 11/17/2022] Open
Abstract
Recent technological development requires new approaches to address the problem of blindness. Such approaches need to be able to ensure that no cells with photosensitive capability remain in the retina. The presented model, Opn4−/− × Pde6brd10/rd10 (O×Rd) double mutant murine, is a combination of a mutation in the Pde6b gene (photoreceptor degeneration) together with a deletion of the Opn4 gene (responsible for the expression of melanopsin in the intrinsically photosensitive retinal ganglion cells). This model has been characterized and compared with those of WT mice and murine animal models displaying both mutations separately. A total loss of pupillary reflex was observed. Likewise, behavioral tests demonstrated loss of rejection to illuminated spaces and a complete decrease in visual acuity (optomotor test). Functional recordings showed an absolute disappearance of various wave components of the full-field and pattern electroretinogram (fERG, pERG). Likewise, visual evoked potential (VEP) could not be recorded. Immunohistochemical staining showed marked degeneration of the outer retinal layers and the absence of melanopsin staining. The combination of both mutations has generated an animal model that does not show any photosensitive element in its retina. This model is a potential tool for the study of new ophthalmological approaches such as optosensitive agents.
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Tirsi A, Orshan D, Wong B, Gliagias V, Tsai J, Obstbaum SA, Tello C. Associations between steady-state pattern electroretinography and estimated retinal ganglion cell count in glaucoma suspects. Doc Ophthalmol 2022; 145:11-25. [PMID: 35377032 PMCID: PMC9259521 DOI: 10.1007/s10633-022-09869-9] [Citation(s) in RCA: 7] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/02/2021] [Accepted: 03/01/2022] [Indexed: 11/24/2022]
Abstract
Purpose To estimate retinal ganglion cell (RGC) count in glaucoma suspects (GS) and ascertain its relationships with steady-state pattern electroretinography (ssPERG) parameters. Methods In this prospective cross-sectional study, 22 subjects (44 eyes) were recruited at the Manhattan Eye, Ear, and Throat Hospital. Subjects underwent complete eye examinations, optical coherence tomography, standard automated perimetry, and ssPERG testing. Eyes were divided into two groups based upon clinical data: healthy subjects and GS. RGC count was estimated using the combined structure–function index. Results Estimated RGC count, average retinal nerve fiber layer thickness (ARNFLT), and average ganglion cell layer and inner plexiform layer thickness (GCIPLT) were reduced in GS eyes (p ≤ 0.001 for all parameters). Pearson correlations revealed that ssPERG magnitude and magnitudeD correlated with ARNFLT (r ≥ 0.53, p < 0.001), GCIPLT (r > 0.38, p < 0.011), and estimated RGC count (r > 0.46, p < 0.002). Six mediation analyses revealed that estimated RGC count mediated the relationships among ssPERG parameters, ARNFLT, and GCIPLT. Conclusion Steady-state PERG parameters demonstrated linear correlations with estimated RGC count. The associations among ssPERG parameters and structural measures were mediated by estimated RGC count. Supplementary Information The online version contains supplementary material available at 10.1007/s10633-022-09869-9.
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Affiliation(s)
- Andrew Tirsi
- Department of Ophthalmology, Manhattan Eye, Ear, and Throat Hospital, Northwell Health, New York, NY, USA.
- Donald and Barbara Zucker School of Medicine at Hofstra/Northwell, Hempstead, NY, USA.
- Diopsys Inc., Pine Brook, New York, NJ, USA.
| | - Derek Orshan
- New York Institute of Technology College of Osteopathic Medicine, Glen Head, NY, USA
- Diopsys Inc., Pine Brook, New York, NJ, USA
| | - Benny Wong
- Donald and Barbara Zucker School of Medicine at Hofstra/Northwell, Hempstead, NY, USA
- Diopsys Inc., Pine Brook, New York, NJ, USA
| | - Vasiliki Gliagias
- Donald and Barbara Zucker School of Medicine at Hofstra/Northwell, Hempstead, NY, USA
- Diopsys Inc., Pine Brook, New York, NJ, USA
| | - Joby Tsai
- Donald and Barbara Zucker School of Medicine at Hofstra/Northwell, Hempstead, NY, USA
- Diopsys Inc., Pine Brook, New York, NJ, USA
| | - Stephen A Obstbaum
- Department of Ophthalmology, Manhattan Eye, Ear, and Throat Hospital, Northwell Health, New York, NY, USA
- Donald and Barbara Zucker School of Medicine at Hofstra/Northwell, Hempstead, NY, USA
- Diopsys Inc., Pine Brook, New York, NJ, USA
| | - Celso Tello
- Department of Ophthalmology, Manhattan Eye, Ear, and Throat Hospital, Northwell Health, New York, NY, USA
- Donald and Barbara Zucker School of Medicine at Hofstra/Northwell, Hempstead, NY, USA
- Diopsys Inc., Pine Brook, New York, NJ, USA
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15
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Structure-function models for estimating retinal ganglion cell count using steady-state pattern electroretinography and optical coherence tomography in glaucoma suspects and preperimetric glaucoma: an electrophysiological pilot study. Doc Ophthalmol 2022; 145:221-235. [PMID: 36161380 PMCID: PMC9653319 DOI: 10.1007/s10633-022-09900-z] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/22/2022] [Accepted: 08/28/2022] [Indexed: 12/29/2022]
Abstract
PURPOSE To derive and validate structure-function models for estimating retinal ganglion cell (RGC) count using optical coherence tomography (OCT) and steady-state pattern electroretinography (ssPERG) parameters in glaucoma suspects (GS) and preperimetric glaucoma (PPG). METHODS In this prospective cross-sectional study, 25 subjects (50 eyes) were recruited at the Manhattan Eye, Ear, and Throat Hospital. Subjects underwent comprehensive eye examinations, OCT, standard automated perimetry (SAP), and ssPERG testing. Eyes were divided into three groups based on the Global Glaucoma Staging System: healthy (N = 30), GS (N = 10), and PPG (N = 10) eyes. The combined structure-function index (CSFI), which estimates retinal ganglion cell count (eRGCCSFI) from SAP and OCT parameters, was calculated in each study subject. Two prediction formulas were derived using a generalized linear mixed model (GLMM) to predict eRGCCSFI from ssPERG parameters, age, and average retinal nerve fiber layer thickness (ARNFLT) in 30 eyes selected at random (training group). GLMM predicted values were cross-validated with the remaining 20 eyes (validation group). RESULTS The ARNFLT, ssPERG parameters magnitude (Mag) and magnitudeD (MagD), and eRGCCSFI were significantly different among study groups (ANOVA p ≤ 0.001). Pearson correlations demonstrated significant associations among ARNFLT, ssPERG parameters, and eRGCCSFI (r2 ≥ 0.31, p < 0.001). Two GLMMs predicted eRGCCSFI from Mag (eRGCMag) and MagD (eRGCMagD), respectively, with significant equations (F(3,18), F(3,19) ≥ 58.37, R2 = 0.90, p < 0.001). eRGCMag and eRGCMagD in the validation group (R2 = 0.89) correlated with eRGCCSFI similarly to the training group. Multivariate pairwise comparisons revealed that eRGCMag and eRGCMagD distinguished between healthy, GS, and PPG eyes (p ≤ 0.035), whereas independent Mag, MagD, and ARNFLT measures did not distinguish between GS and PPG eyes. CONCLUSION This pilot study offers the first combined structure-function models for estimating RGC count using ssPERG parameters. RGC counts estimated with these models were generalizable, strongly associated with CSFI estimates, and performed better than individual ssPERG and OCT measures in distinguishing healthy, GS, and PPG eyes.
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16
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Pattern Electroretinogram Parameters Are Associated with Optic Nerve Morphology in Preperimetric Glaucoma after Adjusting for Disc Area. J Ophthalmol 2021; 2021:8025337. [PMID: 34845426 PMCID: PMC8627351 DOI: 10.1155/2021/8025337] [Citation(s) in RCA: 6] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/26/2021] [Accepted: 09/30/2021] [Indexed: 11/23/2022] Open
Abstract
Purpose We examined the relationships between pattern electroretinogram and optical coherence tomography derived optic nerve head measurements, after controlling for disc area. Methods Thirty-two eyes from 20 subjects with preperimetric glaucoma underwent pattern electroretinogram and optical coherence tomography. Pattern electroretinogram parameters (Magnitude, MagnitudeD, and MagnitudeD/Magnitude ratio) and optic nerve head measurements (rim area, average cup to disc ratio, vertical cup to disc ratio, cup volume, retinal nerve fiber layer thickness sectors, and Bruch's membrane opening-minimum rim width thickness sectors) were analyzed after controlling for disc area. Results Magnitude and MagnitudeD were significantly associated with rim area (r ≥ 0.503, p ≤ 0.004). All pattern electroretinogram parameters significantly correlated with Bruch's membrane opening-minimum rim width sectors—temporal superior and nasal inferior (r = 0.400, p=0.039)—and retinal nerve fiber layer sectors—superior, nasal superior, and inferior (r ≥ 0.428, p ≤ 0.026). Magnitude and MagnitudeD explained an additional 26.8% and 25.2% of variance in rim area (B = 0.174 (95% CI: 0.065, 0.283), p=0.003, and B = 0.160 (95% CI: 0.056, 0.265), p=0.004), respectively. MagnitudeD and MagnitudeD/Magnitude ratio explained an additional 13.4% and 12.8% of the variance in Bruch's membrane opening-minimum rim width global (B = 38.921 [95% CI: 3.872, 73.970], p=0.031, and B = 129.024 (95% CI: 9.589, 248.460), p=0.035), respectively. All Bruch's membrane opening-minimum rim width sectors and retinal nerve fiber layer sectors (nasal superior, nasal inferior, and inferior) were significantly correlated with rim area (r ≥ 0.389, p ≤ 0.045). Conclusion PERG abnormalities can predict rim area loss in preperimetric glaucoma after controlling for disc area. We recommend controlling for disc area to increase diagnostic accuracy in early glaucoma.
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17
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Lim XH, Nongpiur ME, Najjar RP, Hoang QV, Milea D, Wong CW, Husain R, Htoon HM, Aung T, Perera S, Wong TTL. Steady-State Pattern Electroretinography in Eyes with Glaucoma and High Myopia. Clin Ophthalmol 2021; 15:4455-4465. [PMID: 34819717 PMCID: PMC8607345 DOI: 10.2147/opth.s336903] [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: 08/31/2021] [Accepted: 11/02/2021] [Indexed: 11/23/2022] Open
Abstract
Purpose To investigate features of the steady-state pattern electroretinogram (ssPERG) in subjects with glaucoma (G), high myopia (HM; spherical equivalent ≤-6D) and glaucoma with high myopia (GHM). Patients and Methods Our study included 48 participants divided into 3 groups (G, HM, and GHM) who each underwent monocular ssPERG testing with Diopsys NOVA PERG protocols. The ConStim protocol detects distinct topographic patterns of dysfunction 16° and 24° around the central macula. MagD is the amplitude of the average signal and MagD/Mag ratio indicates the consistency of the response. ssPERG indices were compared between groups and correlated with functional (ie, visual field mean deviation (VFMD)) and structural (ie, average retinal nerve fibre layer (RNFL) thickness; Cirrus optical coherence tomography) features. Results Participants had an average age of 59.4±7.6 years. Mean Humphrey VFMD was -14.22 ± 2.88dB, -2.62 ± 1.18dB and -12.80 ± 2.60dB for G, HM and GHM groups, respectively. Mean RNFL thickness was 63.0 ± 8.20μm, 69.5 ± 15.7μm and 60.6 ± 5.0μm for G, HM and GHM groups, respectively. For the 24° setting, no significant differences were noted for any of the parameters. For the 16° setting, MagD was lower in the GHM group compared to the HM group (0.29µV vs 0.52µV; p = 0.02). Significant differences were noted for the MagD/Mag ratio between HM and G groups (0.58 vs 0.40; p = 0.02) and between HM and GHM groups (0.58 vs 0.35; p = 0.002). There were positive correlations between both MagD 16° and MagD/Mag ratio 16° with VFMD (correlation coefficient [r]=0.37, p = 0.009; and r = 0.44, p = 0.002, respectively) and RNFL (r = 0.43, p = 0.002; and r = 0.48, p = 0.001, respectively). Conclusion MagD/Mag ratio at 16° was significantly lower in glaucomatous eyes (with or without high myopia) compared to those with high myopia without glaucoma, suggesting that glaucoma has a distinct impact on MagD/Mag ratio at 16° irrespective of the presence of myopia.
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Affiliation(s)
| | - Monisha Esther Nongpiur
- Singapore National Eye Centre, Singapore.,Singapore Eye Research Institute, Singapore.,Duke-NUS Medical School, Singapore
| | - Raymond P Najjar
- Singapore Eye Research Institute, Singapore.,Duke-NUS Medical School, Singapore
| | - Quan V Hoang
- Singapore National Eye Centre, Singapore.,Singapore Eye Research Institute, Singapore.,Duke-NUS Medical School, Singapore.,Department of Ophthalmology, Edward S. Harkness Eye Institute, Columbia College of Physicians and Surgeons, New York, NY, USA
| | - Dan Milea
- Singapore National Eye Centre, Singapore.,Singapore Eye Research Institute, Singapore.,Duke-NUS Medical School, Singapore
| | - Chee Wai Wong
- Singapore National Eye Centre, Singapore.,Singapore Eye Research Institute, Singapore.,Duke-NUS Medical School, Singapore
| | - Rahat Husain
- Singapore National Eye Centre, Singapore.,Duke-NUS Medical School, Singapore
| | - Hla Myint Htoon
- Singapore Eye Research Institute, Singapore.,Duke-NUS Medical School, Singapore
| | - Tin Aung
- Singapore National Eye Centre, Singapore.,Singapore Eye Research Institute, Singapore.,Duke-NUS Medical School, Singapore.,Department of Ophthalmology, Yong Loo Lin School of Medicine, National University of Singapore, Singapore
| | - Shamira Perera
- Singapore National Eye Centre, Singapore.,Singapore Eye Research Institute, Singapore.,Duke-NUS Medical School, Singapore
| | - Tina Tzee Ling Wong
- Singapore National Eye Centre, Singapore.,Singapore Eye Research Institute, Singapore.,Duke-NUS Medical School, Singapore.,Department of Ophthalmology, Yong Loo Lin School of Medicine, National University of Singapore, Singapore
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18
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Friedel EBN, Tebartz van Elst L, Schmelz C, Ebert D, Maier S, Endres D, Runge K, Domschke K, Bubl E, Kornmeier J, Bach M, Heinrich SP, Nickel K. Replication of Reduced Pattern Electroretinogram Amplitudes in Depression With Improved Recording Parameters. Front Med (Lausanne) 2021; 8:732222. [PMID: 34778295 PMCID: PMC8585854 DOI: 10.3389/fmed.2021.732222] [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: 06/28/2021] [Accepted: 10/06/2021] [Indexed: 12/02/2022] Open
Abstract
Background: The retina has gained increasing attention in non-ophthalmological research in recent years. The pattern electroretinogram (PERG), a method to evaluate retinal ganglion cell function, has been used to identify objective correlates of the essentially subjective state of depression. A reduction in the PERG contrast gain was demonstrated in patients with depression compared to healthy controls with normalization after remission. PERG responses are not only modulated by stimulus contrast, but also by check size and stimulation frequency. Therefore, the rationale was to evaluate potentially more feasible procedures for PERG recordings in daily diagnostics in psychiatry. Methods: Twenty-four participants (12 patients with major depression (MDD) and 12 age- and sex-matched healthy controls) were examined in this pilot study. We investigated PERG amplitudes for two steady-state pattern reversal frequencies (12.5/18.75 rps) and four sizes of a checkerboard stimulus (0.8°, 1.6°, 3.2°, and 16°) to optimize the PERG recordings in MDD patients. Results: Smaller PERG amplitudes in MDD patients were observed for all parameters, whereby the extent of the reduction appeared to be stimulus-specific. The most pronounced decline in the PERG of MDD patients was observed at the higher stimulation frequency and the finest pattern, whilst responses for the largest check size were less affected. Following the PERG ratio protocol for early glaucoma, where similar stimulus dependent modulations have been reported, we calculated PERG ratios (0.8°/16°) for all participants. At the higher frequency (18.75 rps), significantly reduced ratios were observed in MDD patients. Conclusion: The “normalization” of the PERG responses—via building a ratio—appears to be a very promising approach with regard to the development of an objective biomarker of the depressive state, facilitating inter-individual assessments of PERG recordings in patients with psychiatric disorders.
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Affiliation(s)
- Evelyn B N Friedel
- Department of Psychiatry and Psychotherapy, Medical Center-University of Freiburg, Faculty of Medicine, University of Freiburg, Freiburg, Germany.,Eye Center, Medical Center-University of Freiburg, Faculty of Medicine, University of Freiburg, Freiburg, Germany.,Faculty of Biology, University of Freiburg, Freiburg, Germany
| | - Ludger Tebartz van Elst
- Department of Psychiatry and Psychotherapy, Medical Center-University of Freiburg, Faculty of Medicine, University of Freiburg, Freiburg, Germany
| | - Céline Schmelz
- Pfalzklinikum-Clinic for Psychiatry and Neurology, Klingenmünster, Germany
| | - Dieter Ebert
- Department of Psychiatry and Psychotherapy, Medical Center-University of Freiburg, Faculty of Medicine, University of Freiburg, Freiburg, Germany
| | - Simon Maier
- Department of Psychiatry and Psychotherapy, Medical Center-University of Freiburg, Faculty of Medicine, University of Freiburg, Freiburg, Germany
| | - Dominique Endres
- Department of Psychiatry and Psychotherapy, Medical Center-University of Freiburg, Faculty of Medicine, University of Freiburg, Freiburg, Germany
| | - Kimon Runge
- Department of Psychiatry and Psychotherapy, Medical Center-University of Freiburg, Faculty of Medicine, University of Freiburg, Freiburg, Germany
| | - Katharina Domschke
- Department of Psychiatry and Psychotherapy, Medical Center-University of Freiburg, Faculty of Medicine, University of Freiburg, Freiburg, Germany.,Center for Basics in Neuromodulation, Faculty of Medicine, University of Freiburg, Freiburg, Germany
| | - Emanuel Bubl
- Department of Psychiatry and Psychotherapy, Medical Center-University of Freiburg, Faculty of Medicine, University of Freiburg, Freiburg, Germany
| | - Jürgen Kornmeier
- Department of Psychiatry and Psychotherapy, Medical Center-University of Freiburg, Faculty of Medicine, University of Freiburg, Freiburg, Germany.,Institute for Frontier Areas of Psychology and Mental Health, Freiburg, Germany
| | - Michael Bach
- Eye Center, Medical Center-University of Freiburg, Faculty of Medicine, University of Freiburg, Freiburg, Germany
| | - Sven P Heinrich
- Eye Center, Medical Center-University of Freiburg, Faculty of Medicine, University of Freiburg, Freiburg, Germany
| | - Kathrin Nickel
- Department of Psychiatry and Psychotherapy, Medical Center-University of Freiburg, Faculty of Medicine, University of Freiburg, Freiburg, Germany
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Zhu M, Wang H, Li S, Liang X, Zhang M, Dai X, Zhang Y. Flexible Electrodes for In Vivo and In Vitro Electrophysiological Signal Recording. Adv Healthc Mater 2021; 10:e2100646. [PMID: 34050635 DOI: 10.1002/adhm.202100646] [Citation(s) in RCA: 30] [Impact Index Per Article: 10.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/03/2021] [Revised: 05/10/2021] [Indexed: 12/19/2022]
Abstract
A variety of electrophysiological signals (electrocardiography, electromyography, electroencephalography, etc.) are generated during the physiological activities of human bodies, which can be collected by electrodes and thus provide critical insights into health status or facilitate fundamental scientific research. The long-term stable and high-quality recording of electrophysiological signals is the premise for their further applications, leading to demands for flexible electrodes with similar mechanical modulus and minimized irritation to human bodies. This review summarizes the latest advances in flexible electrodes for the acquisition of various electrophysiological signals. First, the concept of electrophysiological signals and the characteristics of different subcategory signals are introduced. Second, the invasive and noninvasive methods are reviewed for electrophysiological signal recording with a highlight on the design of flexible electrodes, followed by a discussion on their material selection. Subsequently, the applications of the electrophysiological signal acquisition in pathological diagnosis and restoration of body functions are discussed, showing the advantages of flexible electrodes. Finally, the main challenges and opportunities in this field are discussed. It is believed that the further exploration of materials for flexible electrodes and the combination of multidisciplinary technologies will boost the applications of flexible electrodes for medical diagnosis and human-machine interface.
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Affiliation(s)
- Mengjia Zhu
- Key Laboratory of Organic Optoelectronics and Molecular Engineering of the Ministry of Education Department of Chemistry Tsinghua University Beijing 100084 P. R. China
| | - Huimin Wang
- Key Laboratory of Organic Optoelectronics and Molecular Engineering of the Ministry of Education Department of Chemistry Tsinghua University Beijing 100084 P. R. China
| | - Shuo Li
- Key Laboratory of Organic Optoelectronics and Molecular Engineering of the Ministry of Education Department of Chemistry Tsinghua University Beijing 100084 P. R. China
| | - Xiaoping Liang
- Key Laboratory of Organic Optoelectronics and Molecular Engineering of the Ministry of Education Department of Chemistry Tsinghua University Beijing 100084 P. R. China
| | - Mingchao Zhang
- Key Laboratory of Organic Optoelectronics and Molecular Engineering of the Ministry of Education Department of Chemistry Tsinghua University Beijing 100084 P. R. China
| | - Xiaochuan Dai
- Department of Biomedical Engineering School of Medicine Tsinghua University Beijing 100084 P. R. China
| | - Yingying Zhang
- Key Laboratory of Organic Optoelectronics and Molecular Engineering of the Ministry of Education Department of Chemistry Tsinghua University Beijing 100084 P. R. China
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Al-Nosairy KO, Hoffmann MB, Bach M. Non-invasive electrophysiology in glaucoma, structure and function-a review. Eye (Lond) 2021; 35:2374-2385. [PMID: 34117381 PMCID: PMC8376952 DOI: 10.1038/s41433-021-01603-0] [Citation(s) in RCA: 7] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/16/2021] [Revised: 05/08/2021] [Accepted: 05/10/2021] [Indexed: 11/09/2022] Open
Abstract
Glaucoma, its early diagnosis, and monitoring of interventions remain an ongoing challenge. We here review developments in functional assessment and its relation to morphology, evaluating recent insights in electrophysiology in glaucoma and highlighting how glaucoma research and diagnostics benefit from combined approaches of OCT and electrophysiological investigations. After concise overviews of OCT and non-invasive electrophysiology in glaucoma, we evaluate commonalities and complementarities of OCT and electrophysiology for our understanding of glaucoma. As a specific topic, the dynamic range (floor effects) of the various techniques is discussed.
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Affiliation(s)
| | - Michael B Hoffmann
- Department of Ophthalmology, Otto-von-Guericke University, Magdeburg, Germany
- Center for Behavioral Brain Sciences, Magdeburg, Germany
| | - Michael Bach
- Faculty of Medicine, Eye Center, Medical Center-University of Freiburg, Freiburg im Breisgau, Germany.
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Aher AJ, Horn FK, Huchzermeyer C, Lämmer R, Kremers J. Responses of Postreceptoral Pathways Elicited by L- and M-Cone Isolating ON- and OFF-Electroretinograms in Glaucoma Patients. Invest Ophthalmol Vis Sci 2021; 62:14. [PMID: 34241626 PMCID: PMC8287051 DOI: 10.1167/iovs.62.9.14] [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] [Indexed: 11/24/2022] Open
Abstract
Purpose To compare the electroretinographical (ERG) responses elicited by L- and M-cone isolating ON- and OFF-sawtooth stimuli in normal subjects and glaucoma patients. Methods Twenty-one normal subjects and 44 primary open-angle glaucoma patients participated in the study. L- and M-cone isolating (18% cone contrast; 284 cd/m2) rapid ON- and rapid OFF-sawtooth (4 Hz) stimuli with two stimulus sizes (full-field (FF) and central 70° diameter) were generated using the triple silent substitution technique. ON- and OFF-response asymmetries were studied by adding the two (to obtain L-add and M-add responses). The initial positive (P) and subsequent late negative (LN) components of the L-add and M-add ERGs were compared between the subject groups and correlated with retinal nerve fiber layer thickness (RNFLT) and pattern ERG responses. Results The responses to L-ON and to M-OFF stimuli and vice versa resembled each other particularly with 70° stimuli. The PL-add amplitudes were not significantly different between the normal subjects and glaucoma patients, whereas the LNL-add amplitude was significantly (P < 0.01) smaller in the glaucoma patients. Both PM-add and LNM-add were not significantly different between the subject groups. The PERG amplitude with 0.8° check sizes and the 0.8°/16° amplitude ratio (PERG ratio) were significantly (P < 0.05) different between the subject groups. The 70° LNL-add amplitude and the 0.8° PERG amplitude were significantly correlated with RNFLT. Conclusions The ERGs to 70° cone isolating sawtooth stimuli reflect cone opponency. The cone opponent ERG responses were not significantly different between glaucoma patients and normal subjects. Luminance driven L-add responses were significantly different, indicating that central luminance signals are mainly affected in glaucoma.
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Affiliation(s)
- Avinash J Aher
- Section for Retinal Physiology, University Hospital Erlangen, Erlangen, Germany
| | - Folkert K Horn
- Department of Ophthalmology, University Hospital Erlangen, Erlangen, Germany
| | - Cord Huchzermeyer
- Department of Ophthalmology, University Hospital Erlangen, Erlangen, Germany
| | - Robert Lämmer
- Department of Ophthalmology, University Hospital Erlangen, Erlangen, Germany
| | - Jan Kremers
- Section for Retinal Physiology, University Hospital Erlangen, Erlangen, Germany.,School of Optometry and Vision Science, University of Bradford, Bradford, West Yorkshire, United Kingdom.,Department of Anatomy II, University of Erlangen-Nürnberg, Erlangen, Germany
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22
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The role of pattern electroretinograms and optical coherence tomography angiography in the diagnosis of normal-tension glaucoma. Sci Rep 2021; 11:12257. [PMID: 34112913 PMCID: PMC8192937 DOI: 10.1038/s41598-021-91813-z] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/28/2020] [Accepted: 05/26/2021] [Indexed: 12/28/2022] Open
Abstract
In this study, we investigated the correlation between pattern electroretinogram (PERG) and optical coherence tomography angiography (OCTA) parameters for diagnosis in patients with normal-tension glaucoma (NTG). Forty-nine normal individuals (49 eyes) and 60 patients with NTG (60 eyes) were enrolled. OCTA and PERG parameters, such as macular vessel density (VD) and the amplitude of N35–P50 and P50–N95, were measured. Correlation analyses were performed between the parameters, and the area under the curve (AUC) was used to identify their diagnostic ability for NTG. Macular VD and the amplitude of N35–P50 and P50–N95 showed significant differences between the normal individuals and patients with NTG. Correlation between P50 and N95 amplitude and macular VD was significant in the normal and early glaucoma groups. Macular VD showed a higher AUC value (0.730) than that of P50–N95 amplitude (0.645) in the early glaucoma group. In the moderate to severe glaucoma group, the AUC value of the amplitude of P50–N95 (0.907) was higher than that of macular VD (0.876). The results indicate that PERG and OCTA parameters may identify glaucoma in its early stage, based on the severity of glaucomatous damage in patients with NTG.
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Al-Nosairy KO, Prabhakaran GT, Pappelis K, Thieme H, Hoffmann MB. Combined Multi-Modal Assessment of Glaucomatous Damage With Electroretinography and Optical Coherence Tomography/Angiography. Transl Vis Sci Technol 2020; 9:7. [PMID: 33200048 PMCID: PMC7645242 DOI: 10.1167/tvst.9.12.7] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/19/2020] [Accepted: 08/30/2020] [Indexed: 01/22/2023] Open
Abstract
Purpose To compare the diagnostic performance and to evaluate the interrelationship of electroretinographical and structural and vascular measures in glaucoma. Methods For 14 eyes of 14 healthy controls and 15 eyes of 12 patients with glaucoma ranging from preperimetric to advanced stages optical coherence tomography (OCT), OCT-angiography (OCT-A), and electrophysiological measures (multifocal photopic negative response ratio [mfPhNR] and steady-state pattern electroretinography [ssPERG]) were applied to assess changes in retinal structure, microvasculature, and function, respectively. The diagnostic performance was assessed via area-under-curve (AUC) measures obtained from receiver operating characteristics analyses. The interrelation of the different measures was assessed with correlation analyses. Results The mfPhNR, ssPERG amplitude, parafoveal (pfVD) and peripapillary vessel density (pVD), macular ganglion cell inner plexiform layer thickness (mGCIPL) and peripapillary retinal nerve fiber layer thickness (pRNFL) were significantly reduced in glaucoma. The AUC for mfPhNR was highest among diagnostic modalities (AUC: 0.88, 95% confidence interval: 0.75-1.0, P < 0.001), albeit not statistically different from that for macular (mGCIPL: 0.76, 0.58-0.94, P < 0.05; pfVD: 0.81, 0.65-0.97, P < 0.01) or peripapillary imaging (pRNFL: 0.85, 0.70-1.0, P < 0.01; pVD: 0.82, 0.68-0.97, P < 0.01). Combined functional/vascular measures yielded the highest AUC (mfPhNR-pfVD: 0.94, 0.85-1.0, P < 0.001). The functional/structural measure correlation (mfPhNR-mGCIPL correlation coefficient [rs]: 0.58, P = 0.001; mfPhNR-pRNFL rs: 0.66, P < 0.001) was stronger than the functional-vascular correlation (mfPhNR-pfVD rs: 0.29, P = 0.13; mfPhNR-pVD rs: 0.54, P = 0.003). Conclusions The combination of ERG measures and OCT-A improved diagnostic performance and enhanced understanding of pathophysiology in glaucoma. Translational Relevance Multimodal assessment of glaucoma damage improves diagnostics and monitoring of disease progression.
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Affiliation(s)
| | | | - Konstantinos Pappelis
- Department of Ophthalmology, University of Groningen, University Medical Center, Groningen, The Netherlands
| | - Hagen Thieme
- Department of Ophthalmology, Otto-von-Guericke University, Magdeburg, Germany
| | - Michael B. Hoffmann
- Department of Ophthalmology, Otto-von-Guericke University, Magdeburg, Germany
- Center for Behavioral Brain Sciences, Magdeburg, Germany
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Alvarez NT, Buschbeck E, Miller S, Le AD, Gupta VK, Ruhunage C, Vilinsky I, Ma Y. Carbon Nanotube Fibers for Neural Recording and Stimulation. ACS APPLIED BIO MATERIALS 2020; 3:6478-6487. [PMID: 35021779 DOI: 10.1021/acsabm.0c00861] [Citation(s) in RCA: 19] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/13/2022]
Abstract
Recordings and stimulations of neuronal electrical activity are topics of great interest in neuroscience. Many recording techniques, and even treatment of neurological disorders, can benefit from a microelectrode that is flexible, chemically inert, and electrically conducting and preferentially transfers electrons via capacitive charge injection. Commercial electrodes that currently exist and other electrodes that are being tested with the purpose of facilitating and improving the electron transport between solid materials and biological tissues still have some limitations. This paper discusses carbon nanotube (CNT)-based microelectrodes to record and stimulate neurons and compares their electron transport capabilities to noble metals such as Au and Ag. The recording ability of electrodes is tested through electroretinography on Sarcophaga bullata fly eyes by using Au and Ag wires and CNT fibers as electrodes. Stimulation is demonstrated through the implantation of Au wire and CNT fibers into the antennas of the Madagascar hissing cockroach (Gromphadorhina portentosa) to control their locomotion. Our results demonstrate that a particular property of the CNT fiber is its high rate of electron transfer, leading to an order of magnitude lower impedance compared to Au and Ag and an impressive 15.09 charge injection capacity. We also established that this carbon nanomaterial assembly performs well for in vivo electrophysiology, rendering it a promising prospect for neurophysiological applications.
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Affiliation(s)
- Noe T Alvarez
- Department of Chemistry, University of Cincinnati, Cincinnati, Ohio 45221, United States
| | - Elke Buschbeck
- Department of Biology, University of Cincinnati, Cincinnati, Ohio 45221, United States
| | - Sydney Miller
- Department of Chemistry, University of Cincinnati, Cincinnati, Ohio 45221, United States
| | - Anh Duc Le
- Department of Biology, University of Cincinnati, Cincinnati, Ohio 45221, United States
| | - Vandna K Gupta
- Department of Chemistry, University of Cincinnati, Cincinnati, Ohio 45221, United States
| | - Chethani Ruhunage
- Department of Chemistry, University of Cincinnati, Cincinnati, Ohio 45221, United States
| | - Ilya Vilinsky
- Department of Biology, University of Cincinnati, Cincinnati, Ohio 45221, United States
| | - Yishan Ma
- Department of Chemistry, University of Cincinnati, Cincinnati, Ohio 45221, United States
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Short-Term Steady-State Pattern Electroretinography Changes Using a Multi-Pressure Dial in Ocular Hypertensive, Glaucoma Suspect, and Mild Open-Angle Glaucoma Patients: A Randomized, Controlled, Prospective, Pilot Study. Ophthalmol Ther 2020; 9:981-992. [PMID: 32939747 PMCID: PMC7708609 DOI: 10.1007/s40123-020-00302-5] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/13/2020] [Accepted: 09/04/2020] [Indexed: 11/21/2022] Open
Abstract
Introduction This study evaluates the effects of the multi-pressure dial (MPD) on steady-state pattern electroretinography (ss-pERG) parameters. The study is a randomized, controlled, prospective, pilot trial in a private practice setting with ocular hypertensive (OHT), glaucoma suspect, and open-angle glaucoma (OAG) subjects. Methods This study included nine patients (64 ± 9.0 years, nine female) with OHT, glaucoma suspect, or mild OAG. One eye of each subject was randomized to receive negative periocular pressure, while the contralateral eye served as the intrasubject control through the goggle without negative pressure. The Diopsys High Contrast Sensitivity ss-pERG protocol was conducted on both eyes of each subject while wearing the MPD device. Application of negative periocular pressure was set at 50% of baseline intraocular pressure for each study eye. Results Following 2 h of negative periocular pressure application, the difference in MagnitudeD (MagD) from baseline for eyes randomized to receive negative periocular pressure (+ 0.17 versus − 0.26) was statistically significant (p = 0.023). Over the same period, the change in MagD/Magnitude (MagD/Mag ratio) from baseline for eyes randomized to receive negative periocular pressure was also higher (+ 0.14 versus − 0.16), compared to the control eyes, approached significance (p = 0.059). Conclusions Following 2 h of MPD wear, the measured MagD and MagD/Mag ratio improved compared to control, suggesting that negative periocular pressure application to the anterior globe can lead to short-term improvement in one measure of retinal ganglion cell function.
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Al-Nosairy KO, Thieme H, Hoffmann MB. Diagnostic performance of multifocal photopic negative response, pattern electroretinogram and optical coherence tomography in glaucoma. Exp Eye Res 2020; 200:108242. [PMID: 32926894 DOI: 10.1016/j.exer.2020.108242] [Citation(s) in RCA: 9] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/27/2020] [Revised: 07/31/2020] [Accepted: 09/08/2020] [Indexed: 11/28/2022]
Abstract
The photopic negative response of the electroretinogram reflects retinal ganglion cell function and consequently aids diagnosis of optic nerve diseases including glaucoma. In this study, we assessed the efficacy of stimulation parameters for electroretinographic recordings of the multifocal photopic negative response (mfPhNR) for the detection of glaucoma and compared the diagnostic accuracy of electrophysiological, structural and functional measures of glaucoma. We compared the diagnostic performance of the mfPhNR for 6 different stimulation rates in a cohort of 24 controls, 10 glaucoma suspects (GLAS ) and 16 glaucoma participants (GLAG). A cross-modal comparison of the mfPhNR/b wave ratio was performed with the pattern electroretinogram (PERG), and the peripapillary retinal nerve fiber layer (pRNFL) thickness. These analyses were based on area under curves (AUC) obtained from receiver-operating-characteristics (ROC) and step-wise regression analyses. We found that compared to the other mfPhNR-conditions, the PhNR/b-wave ratio for the fastest stimulation condition had the highest AUC for GLAS (0.84, P = 0.008, 95%CI: 0.71- 0.98), while the other modalities, i.e., PERG-amplitude and pRNFL had AUCs of 0.78 (P= 0.039), and 0.74 (P < 0.05), respectively. For GLAG , the respective AUCs were 0.78 (P= 0.004), 0.85 (P< 0.001) and 0.87 (P< 0.001). pRNFL was the significant predictor for both mfPhNR/b-wave ratio [t (48) = 4, P = 0.0002] and for PERG amplitude [t (48) = 3.4, P = 0.001]. In conclusion, fast mfPhNR protocols outperform other multifocal PhNR protocols in the identification of glaucomatous damage especially for GLAS and thus aid the early detection of glaucoma, indicating its value as a surrogate marker of early stage ganglion cell dysfunction.
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Affiliation(s)
| | - Hagen Thieme
- Department of Ophthalmology, Otto-von-Guericke University, Magdeburg, Germany
| | - Michael B Hoffmann
- Department of Ophthalmology, Otto-von-Guericke University, Magdeburg, Germany; Center for Behavioral Brain Sciences, Magdeburg, Germany.
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Mavilio A, Sisto D, Prete F, Guadalupi V, Dammacco R, Alessio G. RE-PERG in early-onset Alzheimer's disease: A double-blind, electrophysiological pilot study. PLoS One 2020; 15:e0236568. [PMID: 32790788 PMCID: PMC7425894 DOI: 10.1371/journal.pone.0236568] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/18/2019] [Accepted: 07/08/2020] [Indexed: 12/31/2022] Open
Abstract
PURPOSE To evaluate the ability of re-test pattern electroretinogram (RE-PERG), a non-invasive and fast steady-state PERG, to detect inner retinal bioelectric function anomalies in patients with early-onset Alzheimer's disease (AD). METHODS The study population consisted of 17 patients with AD-related mild cognitive impairment (MCI), 16 patients with vascular dementia (VD)-related MCI, both assessed using the neuropsychological Mini-Mental State Examination (MMSE) and by structural magnetic resonance imaging, and 19 healthy, age-matched normal controls (NC). All participants were visually asymptomatic, had normal or near-normal general cognitive functioning and no or minimal impairments in daily life activities. Visual field (VF) test, optical coherence tomography (OCT) and RE-PERG, sampled in five consecutive blocks of 130 events, were performed. RESULTS There was no statistically significant difference among the three groups with respect to age, VF parameters (mean and pattern standard deviations) and OCT parameters (ganglion cell complex thickness and retinal nerve fiber layer thickness). The mean amplitude in the RE-PERG was significantly lower, but only weakly in the AD group than in NC (p = 0.1) whereas the intrinsic variability of the 2nd harmonic phase was significantly higher in the AD group than in either the VD or NC group (p<0.001). CONCLUSIONS RE-PERG is altered in early-stage AD, showing a reduced amplitude with high intrinsic phase variability. It also allows the discrimination of AD from VD. A high intrinsic variability in the PERG signal, determined using RE-PERG, may thus be a new promising test for neurodegenerative diseases.
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Affiliation(s)
- Alberto Mavilio
- Social Health District, Glaucoma Center, Azienda Sanitaria Locale–Brindisi, Brindisi, Italy
| | - Dario Sisto
- Department of Neurosciences, Institute of Ophthalmology, University of Bari, Bari, Italy
| | - Florenza Prete
- Social Health District, Alzheimer Evaluation Units, Azienda Sanitaria Locale—Brindisi, Brindisi, Italy
| | - Viviana Guadalupi
- Social Health District, Alzheimer Evaluation Units, Azienda Sanitaria Locale—Brindisi, Brindisi, Italy
| | - Rosanna Dammacco
- Department of Neurosciences, Institute of Ophthalmology, University of Bari, Bari, Italy
| | - Giovanni Alessio
- Department of Neurosciences, Institute of Ophthalmology, University of Bari, Bari, Italy
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Prencipe M, Perossini T, Brancoli G, Perossini M. The photopic negative response (PhNR): measurement approaches and utility in glaucoma. Int Ophthalmol 2020; 40:3565-3576. [PMID: 32737731 PMCID: PMC7669808 DOI: 10.1007/s10792-020-01515-0] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/30/2020] [Accepted: 07/17/2020] [Indexed: 11/22/2022]
Abstract
Purpose Visual electrophysiological testing continues to generate interest among glaucoma experts because of its potential help in clarifying disease pathophysiology and promoting early detection of glaucomatous damage. The photopic negative response (PhNR) is a slow negative component of the full-field electroretinogram that has been shown to provide specific information about retinal ganglion cells (RGCs) activity. The purpose of this article is to review the literature to explore the currently available measurement methods and the utility of PhNR in glaucoma diagnostic process. Methods We gathered publications related to the origins, types of stimuli used, measurements methods and applications of the PhNR of ERG in animal models and humans through a search of the literature cited in PubMed. Search terms were: “PhNR”, “photopic negative response”, “glaucoma”, “glaucomatous optic neuropathy”, “ERG”, “electroretinogram”. Results The most reliable PhNR measurements are obtained using a red stimulus on a blue background, without requiring refractive correction, fixation monitoring, or ocular media transparency. Given its direct correlation with RGCs response, the PhNR measured as baseline-to-trough (BT) represents the most reliable parameter of evaluation. Glaucoma patients with evident perimetric defects show pathologic PhNR values. Even though the PhNR is promising in detecting early RGCs impairment, distinguishing between healthy subjects and suspect patients at risk of developing glaucomatous damage still remains challenging. Conclusion The PhNR is a useful additional tool to explore disorders that affect the innermost retina, including glaucoma and other forms of optic neuropathy. In particular, comparing reports of the standard examinations (optic disc assessment, OCT RNFL measurement, standard automated perimetry) with the results of electrophysiological tests may be helpful in solving clinical diagnostic and management dilemmas. On the one hand, the PhNR of the ERG can examine the parvocellular pathways; on the other hand, the steady-state pattern ERG optimized for glaucoma screening (PERGLA) can explore the magnocellular pathways. This could give ophthalmologists a useful feedback to identify early RGCs alterations suggestive of glaucoma, stratify the risk and potentially monitor disease progression.
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Affiliation(s)
- Matteo Prencipe
- Department of Surgical, Medical, Molecular Pathology and of Critical Area, University of Pisa, Pisa, Italy.
| | - Tommaso Perossini
- Studio Oculistico Associato Mario and Tommaso Perossini, Livorno, Italy
| | | | - Mario Perossini
- Studio Oculistico Associato Mario and Tommaso Perossini, Livorno, Italy
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Al-Nosairy KO, van den Bosch JJON, Pennisi V, Mansouri K, Thieme H, Choritz L, Hoffmann MB. Use of a novel telemetric sensor to study interactions of intraocular pressure
and ganglion-cell function in glaucoma. Br J Ophthalmol 2020; 105:661-668. [DOI: 10.1136/bjophthalmol-2020-316136] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/25/2020] [Revised: 05/07/2020] [Accepted: 06/03/2020] [Indexed: 11/03/2022]
Abstract
Aims
(1) To test the feasibility of simultaneous steady-state pattern
electroretinogram (ssPERG) and intraocular pressure (IOP) measurements with an
implanted IOP sensor. (2) To explore the scope of this approach for detecting
PERG changes during IOP manipulation in a model of lateral decubitus
positioning (LDP; lateral position).
Methods
15 healthy controls and 15 treated glaucoma patients participated in the
study. 8 patients had an IOP sensor (Eyemate-IO, Implandata Ophthalmic Products
GmbH) in the right eye (GLAIMP) and 7 had no sensor and
with glaucoma in the left eye. (1) We compared PERGs with and without
simultaneous IOP read-out in GLAIMP. (2) All participants
were positioned in the following order: sitting1 (S1), right LDP
(LDR), sitting2 (S2), left LDP
(LDL) and sitting3 (S3). For each position, PERG
amplitudes and IOP were determined with rebound tonometry (Icare TA01i) in all
participants without the IOP sensor.
Results
Electromagnetic intrusions of IOP sensor read-out onto ssPERG recordings
had, due to different frequency ranges, no relevant effect on PERG amplitudes.
IOP and PERG measures were affected by LDP, for example, IOP was increased
during LDR versus S1 in the lower eyes of
GLAIMP and controls (5.1±0.6 mmHg,
P0.025=0.00004 and 1.6±0.6 mmHg,
P0.025=0.02, respectively) and PERG amplitude was
reversibly decreased (−25±10%, P0.025=0.02 and −17±5%,
P0.025, respectively).
Conclusions
During LDP, both IOP and PERG changed predominantly in the lower eye. IOP
changes induced by LDP may be a model for studying the interaction of IOP and
ganglion-cell function.
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Jung KI, Jeon S, Shin DY, Lee J, Park CK. Pattern Electroretinograms in Preperimetric and Perimetric Glaucoma. Am J Ophthalmol 2020; 215:118-126. [PMID: 32087144 DOI: 10.1016/j.ajo.2020.02.008] [Citation(s) in RCA: 19] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/22/2019] [Revised: 02/04/2020] [Accepted: 02/07/2020] [Indexed: 10/25/2022]
Abstract
PURPOSE To investigate whether visual function can be graded in detail using pattern electroretinogram (PERG) in preperimetric to perimetric glaucoma. DESIGN Cross-sectional observational study. METHODS Twenty-six normal subjects, 113 preperimetric glaucoma patients (which included glaucoma suspect patients), and 52 early perimetric glaucoma patients with a mean deviation (MD) >-10 dB were included. Structural and functional measurements were performed using spectral-domain optical coherence tomography and a commercial ERG stimulator, respectively. RESULTS The average retinal nerve fiber layer (RNFL) and ganglion cell-inner plexiform layer (GCIPL) thickness were thinnest in the perimetric group, followed by the preperimetric group and the control group (P < .001). PERG N95 amplitude was the largest in the control group, followed by the preperimetric group and the perimetric group (P < .001). Among the preperimetric glaucoma patients, presence of the RNFL defect was associated with lower PERG N95 amplitude (P = .013). The N95 amplitude showed a significant relationship with average RNFL thickness (r = 0.336, P < .001) and GCIPL thickness (r = 0.376, P < .001). In the preperimetric group with the RNFL defect, the N95 amplitude showed larger areas under the receiver operating characteristic curve (0.779) than the MD (0.533, P = .005). CONCLUSIONS PERG N95 amplitudes decreased from the control to preperimetric glaucoma group and were reduced more in perimetric glaucoma. The functional assessment for detecting early glaucomatous damage could be complemented by PERG N95 amplitude. Usefulness of PERG parameters except N95 amplitude seemed to be limited in a clinical setting because of relatively low diagnostic performance in preperimetric glaucoma.
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Long-term PERG monitoring of untreated and treated glaucoma suspects. Doc Ophthalmol 2020; 141:149-156. [PMID: 32152920 DOI: 10.1007/s10633-020-09760-5] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/06/2019] [Accepted: 03/02/2020] [Indexed: 10/24/2022]
Abstract
PURPOSE To investigate long-term structural and functional progression of untreated and treated glaucoma suspects (UGS and TGS). METHODS Retrospective analysis of serial steady-state pattern electroretinogram (PERG), mean retinal nerve fiber layer thickness (RNFLT), and standard automated perimetry mean deviation (SAP-MD) in UGS (N = 20) and TGS (N = 18). Outcome measures were the rates of change (linear regression slopes) of PERG amplitude, PERG phase, mean RNFLT, and SAP-MD over 9.8 ± 1.3 years (15.6 ± 4.2 visits). RESULTS The number of patients with significant (P < 0.05) progression slopes for PERG amplitude, PERG phase, RNFLT, and SAP-MD was, respectively, UGS: 5, 0, 4, 2; TGS: 8, 2, 6, 5. In UGS, outcome measures were not correlated with each other. In TGS, both PERG amplitude and RNFLT were significantly (P < 0.05) correlated with SAP-MD (R ≥ 0.58), while PERG amplitude and RNFLT were not correlated with each other (R = 0.43, P = 0.064). The rate of change of SAP-MD was predicted (P < 0.05) by a linear combination of RNFLT slope and PERG amplitude slope. CONCLUSIONS Results substantiate and extend previous results showing that steady-state PERG amplitude progressively decreased over time in a proportion of glaucoma suspects, with relatively steeper slope in TGS compared to UGS. RNFLT progression also had a steeper slope in TGS compared to UGS; however, progressions of PERG amplitude and RNFLT were not significantly correlated. Both PERG progression and RNFLT progression independently contribute to prediction of visual field progression.
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Utility of the Modified Isolated-check Visual Evoked Potential Technique in Functional Glaucoma Assessment. J Glaucoma 2020; 29:258-263. [DOI: 10.1097/ijg.0000000000001439] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/25/2022]
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Abstract
PURPOSE To evaluate the ability of macular and multifocal (mf) pattern electroretinogram (PERG) to differentiate preperimetric glaucoma (PG) and glaucoma with hemifield loss (GHL) from controls, to compare the discrimination ability of PERG and fourier-domain optical coherence tomography (FD-OCT), and to assess the relationship between measurements. PATIENTS AND METHODS Standard automated perimetry, steady-state and transient PERG and mfPERG measurements were obtained from PG (n=14, 24 eyes), GHL (n=5, 7 eyes), and controls (n=19, 22 eyes). Circumpapillary retinal nerve fiber layer (cpRNFL), full-thickness macula, and segmented macular layer thicknesses on FD-OCT were investigated. Measurements were compared using mixed effects linear models. The relationships between measurements and the diagnostic performance of each technology were assessed. RESULTS Compared with controls, average P50 peak time transient PERG responses were reduced in PG and GHL, whereas average latency and amplitude steady-state and mfPERG responses were abnormal only in GHL. cpRNFL and macular thickness measurements in PG and GHL differed significantly from controls. A significant relationship was found between PERG and most FD-OCT or SAP parameters. Partial least squares discriminant analysis revealed that OCT parameters, along with mfPERG and transient PERG parameters had similar ability to discriminate PG and GHL from healthy controls. CONCLUSIONS PERG and OCT parameters may be abnormal, with significant correlations between measurements, in PG eyes. Both technologies may be useful for detection of early glaucoma.
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Mavilio A, Sisto D, Ferreri P, Dammacco R, Alessio G. RE-PERG, a new paradigm for glaucoma diagnosis, in myopic eyes. Clin Ophthalmol 2019; 13:1315-1322. [PMID: 31440021 PMCID: PMC6664252 DOI: 10.2147/opth.s211337] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/06/2019] [Accepted: 06/21/2019] [Indexed: 12/20/2022] Open
Abstract
Purpose To evaluate reliability of steady-state pattern electroretinogram (ssPERG) phase variability in re-test (procedure called RE-PERG) in the presence of myopia, which is known to affect ssPERG amplitude, in glaucomatous patients (GP), normal controls (NC), and myopic patients (MY). Methods The procedure was performed on 50 GP, 35 NC, and 19 MY. All subjects were examined with RE-PERG, spectral-domain coherence tomography (SD-OCT), and standard automated perimetry (SAP). Standard deviation of phase (ssPERG SDph) and mean amplitude value (ssPERG Amp) of second harmonic (2ndH) were correlated, by means of one-way ANOVA and Pearson correlation, with mean deviation (MD) and pattern standard deviation (PSD) assessed by SAP and retinal nerve fiber layer (RNFL) and ganglion cell complex (GCC) thickness assessed by SD-OCT. Receiving operating characteristics were calculated in cohort populations with and without myopia. Results GP showed significant differences from the control group for MD, PSD, RNFL, GCC, ssPERG Amp, and ssPERG SDph; GP also showed significant differences from the MY group for all the parameters except for ssPERG Amp, which is reduced in both groups. In GP group, ssPERG Amp showed a specificity of 82.1% (95% confidence interval [CI]I: 66.5–92.5). In MY group, ssPERG Amp was reduced in 58% of the patients. As a consequence of this, in GP and MY groups, considered as a whole, total specificity dropped to 70.69% (95% CI: 57.3–81.9). In the GP group, ssPERG SDph showed a specificity of 84.6% (95% CI: 69.5–91.1). In both GP and MY groups, considered as a whole, ssPERG SDph total specificity increased from 84.6% to 93.1% (95% CI: 83.3–98.1). Conclusion Intrinsic phase variability of ssPERG is not influenced by myopia, even in the presence of fundus alterations.
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Affiliation(s)
- Alberto Mavilio
- Social Health District, Glaucoma Center, Azienda Sanitaria Locale, Brindisi, Italy
| | - Dario Sisto
- Department of Neurosciences, Institute of Ophthalmology, University of Bari, Bari, Italy
| | - Paolo Ferreri
- Department of Neurosciences, Institute of Ophthalmology, University of Bari, Bari, Italy
| | - Rosanna Dammacco
- Department of Neurosciences, Institute of Ophthalmology, University of Bari, Bari, Italy
| | - Giovanni Alessio
- Department of Neurosciences, Institute of Ophthalmology, University of Bari, Bari, Italy
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Abstract
PURPOSE To test whether pattern electroretinogram (PERG) can early detect retinal ganglion cells dysfunction in ocular hypertension. DESIGN Cross-sectional observational study. PARTICIPANTS The study included 3 groups: control, primary open-angle glaucoma (POAG) and ocular hypertension (OHT) groups with 30 eyes in each group. MATERIALS AND METHODS Visual fields were examined using automated perimetry with central 24-2 program. Optical coherent tomography (OCT) was done to assess the neuroretinal rim area, vertical cup/disc ratio, and average superior and inferior retinal nerve fiber layer thickness. PERG was recorded using skin electrodes. Amplitude and latency of P50 and N95 were documented. RESULTS PERG data: the mean P50 and N95 latency were significantly higher in the POAG group and the OHT group compared with the control group (P<0.001, <0.001, respectively). Also, the mean P50 and N95 amplitude were significantly lower in the POAG group and the OHT group compared with the control group (P<0.001,<0.001, respectively). In the POAG group, there was a significant negative correlation between PSD on one hand and P50 amplitude (r=-0.620, P=0.001) and N95 amplitude (r=-0.61, P<0.001) on the other hand. Also, the mean deviation was positively correlated with P50 amplitude (r=0.51, P=0.007) and N95 amplitudes (r=0.50, P=0.002). However, there was no significant correlation between PERG parameters and OCT parameters. In the OHT group, PERG parameters did not correlate with visual field and OCT parameters. CONCLUSIONS PERG can detect the dysfunctional, but still live retinal ganglion cells earlier than OCT in OHT cases, allowing the early start of treatment that can restore the ganglion cell function before irreversible damage occurs.
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Comparison Of Xenon And LED Light Sources In Electroretinography And Visual Evoked Potential Measurements. ANADOLU KLINIĞI TIP BILIMLERI DERGISI 2019. [DOI: 10.21673/anadoluklin.472427] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022] Open
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Jung KI, Jeon S, Kim YC, Park CK. Comparison of pattern electroretinograms of glaucoma patients with parafoveal scotoma versus peripheral nasal step. Sci Rep 2019; 9:3547. [PMID: 30837586 PMCID: PMC6401083 DOI: 10.1038/s41598-019-39948-y] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/11/2018] [Accepted: 02/01/2019] [Indexed: 12/12/2022] Open
Abstract
Retinal ganglion cells are distributed disproportionately with retinal eccentricity. Pattern electroretinogram (PERG) stimuli resulted in reduced responses with more eccentric stimuli. Therefore, we investigated whether PERG amplitude is associated with the location of visual field (VF) defect in primary open-angle glaucoma. Data from Twenty-nine glaucoma patients with a parafoveal scotoma (PFS) within the central 10° of fixation, 23 glaucoma patients with a peripheral nasal step (PNS), and 27 normal control subjects were analyzed in this study. Electroretinograms (ERGs) were obtained using a commercial ERG stimulator (Neuro-ERG). The thickness of the ganglion cell-inner plexiform layer (GCIPL) was measured using spectral-domain optical coherence tomography. A lower N95 amplitude was observed in both PFS and PNS compared to the normal control (Both P < 0.001). The N95 amplitude of the PFS group was significantly lower than that of the PNS group (P = 0.034). Average GCIPL thickness correlated positively with N95 amplitude (r = 0.368, P = 0.002), but did not correlate significantly with global mean sensitivity (r = 0.228, P = 0.073) or mean deviation on 24-2 standard automated perimetry (r = 0.173, P = 0.176). In conclusion, parafoveal VF defects were associated with the lower PERG amplitude. Therefore, it is necessary to take into account the location of VF defects in evaluating PERGs of glaucoma patients.
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Affiliation(s)
- Kyoung In Jung
- Department of Ophthalmology, Seoul St. Mary's Hospital, College of Medicine, The Catholic University of Korea, Seoul, Republic of Korea
| | - Sooji Jeon
- Department of Ophthalmology, Seoul St. Mary's Hospital, College of Medicine, The Catholic University of Korea, Seoul, Republic of Korea
| | - Yong Chan Kim
- Department of Ophthalmology, Hallym University College of Medicine, Chuncheon Sacred Heart Hospital, Chuncheon, Republic of Korea
| | - Chan Kee Park
- Department of Ophthalmology, Seoul St. Mary's Hospital, College of Medicine, The Catholic University of Korea, Seoul, Republic of Korea.
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Abstract
Purpose of review Currently, the clinical evaluation of neuro-ophthalmologic diseases are mainly focused on identifying stages where structural or functional damage occur. Recognition of retinal ganglion cell (RGC) functional patterns as well as monitoring RGC dysfunction can be performed using steady-state pattern electroretinogram (PERG). The analysis of the amplitude and latency shift aid on providing information on early damage or monitoring of the RGC, allowing for prompt clinical intervention and management modification, potentially changing the natural history of the disease. The purpose of this article is to review the latest findings in PERG, in early manifest glaucoma, non arteritic ischemic optic neuropathy, multiple sclerosis with unilateral recovered optic neuritis and its fellow eyes. Recent Findings The steady-state PERG responses provide new and early specific information in neuro-ophthalmic diseases affecting the inner retina. Summary Steady state PERG presents specific amplitude and latency outcomes based on the neuro-ophthalmic disease affecting the inner retina, allowing early recognition of changes at the level of RGC and the degree of RGC dysfunction. In addition, PERG alterations may be induced in healthy subjects as well as susceptible eyes using different stress tests such as head down tilting or water drinking tests.
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Hassankarimi H, Noori SMR, Jafarzadehpour E, Yazdani S, Radinmehr F. Analysis of pattern electroretinogram signals of early primary open-angle glaucoma in discrete wavelet transform coefficients domain. Int Ophthalmol 2019; 39:2373-2383. [PMID: 30725244 DOI: 10.1007/s10792-019-01077-w] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/23/2017] [Accepted: 01/25/2019] [Indexed: 10/27/2022]
Abstract
PURPOSE To evaluate discrete wavelet transform coefficients and identify descriptors of pattern electroretinogram (PERG) waveforms in order to determine PERG characteristics for optimizing the diagnosis of early primary open-angle glaucoma (POAG). METHODS Pattern electroretinogram was performed in 30 normal eyes and 30 eyes with primary open-angle glaucoma according to the ISCEV protocol. The check size was 0.8° and 16°, and the color was black/white in both groups. The results were analyzed in time domain (TD) and discrete wavelet transform (DWT) using the MATLAB software. The mean value, standard deviation, and relative energy of level 6 and 7 detail coefficients (d6, d7) and level 7 approximation coefficients (a7) of Daubechies 4 (db4), Daubechies 8 (db8), Symlet 5 (sym5), Symlet 7 (sym7), and Coiflet 5 (coif5) wavelets were calculated. In all the mentioned wavelets, DWT descriptors were extracted. Signals were reconstructed by inverse DWT. All data obtained by TD and DWT analyses were compared between the two groups. RESULTS In both check sizes, a significant attenuation of N95 amplitude was seen in the patient group. The relative energy of a7 of db8 increased significantly in the POAG group in the 0.8° check size. In larger check stimuli, the relative energy of d7 of coif5 decreased significantly and the standard deviation of d7 of sym7 increased markedly in glaucomatous patients (P < 0.05). In small stimuli, N95 descriptor (7N) of db8 had the highest value and showed a significant increase as compared to the POAG group. In the 16° check size, there was no significant difference. A strong correlation was seen between reconstructed signals and originals (r = 0.99). CONCLUSION The DWT can quantify PERG responses more accurately. In agreement with TD and wavelet coefficients domain results, 7N of db8 decomposition can be used as a good indicator for early detection of POAG.
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Affiliation(s)
- Homa Hassankarimi
- Department of Medical Physics, School of Medicine, Iran University of Medical Sciences, Tehran, Iran
| | - Seyed Mohammad Reza Noori
- Departments of Medical Physics and Biomedical Engineering, School of Medicine, Tehran University of Medical Sciences, Tehran, Iran
| | - Ebrahim Jafarzadehpour
- Department of Optometry, School of Rehabilitation Science, Iran University of Medical Sciences, Tehran, Iran. .,Department of Optometry, Faculty of Rehabilitation, Iran University of Medical Sciences, Shahnazary St., Mohseni Sq., Mirdamad Blvd., Tehran, Iran.
| | - Shahin Yazdani
- Ophthalmic Research Center, Shahid Beheshti University of Medical Sciences, Tehran, Iran
| | - Fatemeh Radinmehr
- Department of Optometry, School of Rehabilitation Science, Iran University of Medical Sciences, Tehran, Iran
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Anders LM, Heinrich SP, Lagrèze WA, Joachimsen L. Little effect of 0.01% atropine eye drops as used in myopia prevention on the pattern electroretinogram. Doc Ophthalmol 2019; 138:85-95. [PMID: 30680489 DOI: 10.1007/s10633-019-09671-0] [Citation(s) in RCA: 12] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/10/2018] [Accepted: 01/15/2019] [Indexed: 11/30/2022]
Abstract
PURPOSE Daily administration of 0.01% atropine eye drops is a promising approach for myopia control. The mechanism of action is believed to involve the dopaminergic system of the retina, triggering an increased release of dopamine. Previous studies in psychiatric condition such as major depression suggest that pattern electroretinogram (PERG) amplitudes are modulated by changes in retinal dopamine. It is thus plausible that atropine eye drops could have an effect on PERG amplitudes. The present study was designed to test this, assessing the difference in amplitude between contrast levels and the ratio of amplitudes between check sizes as primary endpoints. METHODS We included 14 participants with no more than ± 2 diopters of ametropia and visual acuity of at least 1.0. One eye was chosen randomly in each participant for atropine application (14 days, one drop of 0.01% atropine solution once daily before bedtime). We recorded two sets of steady-state PERG recordings: one with different contrasts (25% and 98%) and one with different check sizes (0.8° and 17°). Near-point distance, near visual acuity, and pupil diameter were measured additionally. RESULTS The recordings to different contrasts did not show atropine-related changes of PERG amplitude. A small increase by 6% of the amplitude difference between contrast levels with atropine application was not significant (p = 0.08). Raw amplitudes in the check size condition increased with atropine by 17% (p < 0.01) and 10% (p < 0.03) for small and large checks, respectively, without a significant concomitant effect on the amplitude ratio. Pupil size was significantly affected (median increase 0.5 mm, p < 0.002). However, neither of the experimental conditions was associated with a significant correlation between pupil size and PERG effects. CONCLUSION The effects on PERG primary endpoints after the 14-day period of atropine administration were small, especially compared to effect sizes in major depression, and statistically insignificant. Effects on raw amplitude were inconsistent. The present results suggest that retinal processing as reflected by PERG does not sizably change following a treatment regimen with atropine that is typical for myopia control.
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Affiliation(s)
- Lisa-Marie Anders
- Eye Center, Medical Center, University of Freiburg, Killianstr. 5, 79106, Freiburg, Germany.
- Faculty of Medicine, University of Freiburg, Freiburg, Germany.
| | - Sven P Heinrich
- Eye Center, Medical Center, University of Freiburg, Killianstr. 5, 79106, Freiburg, Germany
- Faculty of Medicine, University of Freiburg, Freiburg, Germany
| | - Wolf A Lagrèze
- Eye Center, Medical Center, University of Freiburg, Killianstr. 5, 79106, Freiburg, Germany
- Faculty of Medicine, University of Freiburg, Freiburg, Germany
| | - Lutz Joachimsen
- Eye Center, Medical Center, University of Freiburg, Killianstr. 5, 79106, Freiburg, Germany
- Faculty of Medicine, University of Freiburg, Freiburg, Germany
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Salgarello T, Giudiceandrea A, Calandriello L, Marangoni D, Colotto A, Caporossi A, Falsini B. Pattern Electroretinogram Detects Localized Glaucoma Defects. Transl Vis Sci Technol 2018; 7:6. [PMID: 30221072 PMCID: PMC6136848 DOI: 10.1167/tvst.7.5.6] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/15/2017] [Accepted: 06/19/2018] [Indexed: 11/24/2022] Open
Abstract
Purpose We evaluated the clinical ability of pattern electroretinogram (PERG) to detect functional losses in the affected hemifield of open-angle glaucoma patients with localized perimetric defects. Methods Hemifield (horizontally-defined) steady-state PERGs (h-PERGs) were recorded in response to 1.7 c/deg alternating gratings from 32 eyes of 29 glaucomatous patients with a perimetric, focal one-hemifield defect, 10 eyes of 10 glaucomatous patients with a diffuse perimetric defect, and 18 eyes of 18 age-matched normal subjects. Standard automated perimetry (SAP) and spectral-domain optical coherence tomography (SD-OCT) for retinal nerve fiber layer (RNFL) thickness also were performed. h-PERG amplitudes and ratios, calculated corresponding hemifield perimetric deviations, as well as hemiretina RNFL thicknesses were analyzed. Results h-PERG amplitudes, perimetric deviations, and RNFL thicknesses showed losses (P < 0.001) when comparing affected with unaffected hemifields of localized glaucomatous eyes. No differences were found in h-PERG amplitudes between hemifields of normal or diffuse glaucomatous eyes. h-PERG amplitude ratios (affected/unaffected hemifield) in localized glaucoma were lower (P < 0.001) than the ratios from normal or diffuse glaucomatous eyes. The areas under the receiver operating characteristic curves for h-PERG amplitude ratios, comparing localized-defect glaucomatous eyes with normal or diffuse glaucomatous eyes, were 0.93 and 0.91, respectively. Conclusions h-PERG assessment showed good diagnostic accuracy to confirm localized glaucomatous defects detected perimetrically. This test may be particularly useful in cognitively impaired patients or young/nonverbal patients unable to provide reliable visual fields. Translational Relevance h-PERG provides a sensitive objective measure to confirm focal losses detected with SAP and/or RNFL thickness analysis.
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Affiliation(s)
- Tommaso Salgarello
- 1Institute of Ophthalmology, Fondazione Policlinico Universitario A. Gemelli IRCCS, Roma, Italia
| | - Andrea Giudiceandrea
- 1Institute of Ophthalmology, Fondazione Policlinico Universitario A. Gemelli IRCCS, Roma, Italia.,2Institute of Ophthalmology, Università Cattolica del Sacro Cuore, Roma, Italia
| | - Luigi Calandriello
- 1Institute of Ophthalmology, Fondazione Policlinico Universitario A. Gemelli IRCCS, Roma, Italia.,2Institute of Ophthalmology, Università Cattolica del Sacro Cuore, Roma, Italia
| | - Dario Marangoni
- 1Institute of Ophthalmology, Fondazione Policlinico Universitario A. Gemelli IRCCS, Roma, Italia.,2Institute of Ophthalmology, Università Cattolica del Sacro Cuore, Roma, Italia
| | - Alberto Colotto
- 2Institute of Ophthalmology, Università Cattolica del Sacro Cuore, Roma, Italia
| | - Aldo Caporossi
- 1Institute of Ophthalmology, Fondazione Policlinico Universitario A. Gemelli IRCCS, Roma, Italia.,2Institute of Ophthalmology, Università Cattolica del Sacro Cuore, Roma, Italia
| | - Benedetto Falsini
- 1Institute of Ophthalmology, Fondazione Policlinico Universitario A. Gemelli IRCCS, Roma, Italia.,2Institute of Ophthalmology, Università Cattolica del Sacro Cuore, Roma, Italia
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Kurysheva NI, Maslova EV, Zolnikova IV, Fomin AV, Lagutin MB. A comparative study of structural, functional and circulatory parameters in glaucoma diagnostics. PLoS One 2018; 13:e0201599. [PMID: 30138396 PMCID: PMC6107119 DOI: 10.1371/journal.pone.0201599] [Citation(s) in RCA: 23] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/14/2017] [Accepted: 07/18/2018] [Indexed: 11/18/2022] Open
Abstract
PURPOSE To compare the diagnostic accuracy of structural parameters, vessel density (VD) measured by optical coherence tomography angiography (OCTA), and electrophysiological testing in diagnosis of primary open-angle glaucoma (POAG). METHODS 35 healthy participants and 90 POAG subjects underwent the measurement of whole image en face (wi) VD in the disc/peripapillary region and macula, the retinal nerve fiber layer (RNFL), and the average thickness of ganglion cell complex (GCC), pattern electroretinograms and pattern visual evoked potentials. The area under the receiver operating characteristic curve (AUC) was assessed for each parameter to differentiate early POAG from healthy eyes and between the POAG stages. RESULTS To distinguish early POAG from healthy eyes, the parameters with the highest AUC were detected: P50 amplitude of transient pattern electroretinogram, 1° (AUC 0.93, p = 0.002), P1 component of steady-state pattern electroretinogram (AUC 0.92, p = 0.003), P100 amplitude of pattern visual evoked potential, 1° (AUC 0.84, p = 0.013), wiVD macula superficial (AUC 0.80, p = 0.001), wiVD Disc (AUC 0.74, p = 0.016), GCC (AUC 0.74, p = 0.016) and to distinguish early POAG from the moderate to severe POAG: inferotemporal peripapillary VD (AUC 0.94, p < 0.0001) and focal loss volume of GCC (AUC 0.92, p < 0, 001). CONCLUSIONS Our results demonstrate the importance of measuring the microcirculation parameters in the macular area along with PERGs and PVEPs for the early detection of glaucoma. VD in the inferotemporal sector of the peripapillary retina and focal loss volume of the GCC are important for monitoring of the disease. The inclusion of OCTA, PERGs and PVEPs in glaucoma diagnostics may improve its early detection and monitoring.
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Affiliation(s)
- Natalia Ivanovna Kurysheva
- Consultative-Diagnostic Department of Ophthalmology Center of the Federal Medical and Biological Agency of the Russian Federation, A.I. Burnazyan Federal Medical and Biophysical Center of FMBA, Ophthalmological Department of the Institute of Improvement of Professional Skill of FMBA, Moscow, Russian Federation
- * E-mail:
| | - Ekaterina Vladimirovna Maslova
- Consultative-Diagnostic Department of Ophthalmology Center of the Federal Medical and Biological Agency of the Russian Federation, A.I. Burnazyan Federal Medical and Biophysical Center of FMBA, Ophthalmological Department of the Institute of Improvement of Professional Skill of FMBA, Moscow, Russian Federation
| | | | - Alexey Valentinovich Fomin
- National Research Institute of Eye Diseases, Russian Academy of Medical Sciences, Moscow, Russian Federation
| | - Mikhail Borisovich Lagutin
- Lomonosov Moscow State University, Faculty of Mechanics and Mathematics, Department of Mathematical Statistics and Stochastic Processes, Moscow, Russian Federation
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Fry LE, Fahy E, Chrysostomou V, Hui F, Tang J, van Wijngaarden P, Petrou S, Crowston JG. The coma in glaucoma: Retinal ganglion cell dysfunction and recovery. Prog Retin Eye Res 2018; 65:77-92. [DOI: 10.1016/j.preteyeres.2018.04.001] [Citation(s) in RCA: 38] [Impact Index Per Article: 6.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/18/2017] [Revised: 03/18/2018] [Accepted: 04/03/2018] [Indexed: 01/07/2023]
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Retinal ganglion cell function in recovered optic neuritis: Faster is not better. Clin Neurophysiol 2018; 129:1813-1818. [PMID: 29981956 DOI: 10.1016/j.clinph.2018.06.012] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/21/2018] [Revised: 05/25/2018] [Accepted: 06/13/2018] [Indexed: 01/04/2023]
Abstract
OBJECTIVE To assess residual retinal ganglion cell (RGC) function in patients with recovered optic neuritis (ON) and multiple sclerosis (MS). METHODS Age-matched controls (C, n = 32) and MS patients (n = 17) with history of ON in one eye but normal visual acuity and color vision were tested with steady-state Pattern Electroretinogram (PERG). Light Emitting Diodes (LED)-generated bar gratings, robust signal averaging and Fourier analysis were used to assess response amplitude and latency. RESULTS PERG amplitude was similar for C, ON and fellow eyes (FE) (P = 0.4), but PERG latency was shortened in ON by 3.2 ms (P = 0.002) and in FE by 2.0 ms (P = 0.02) and was correlated (P < 0.01) with both Retinal Nerve Fiber Layer (RNFL) and Ganglion Cell Inner Plexiform Layer (GCIPL) thicknesses. PERG latency shortening could be simulated in control subjects (n = 8) by dioptrically blurring the edges of gratings (high spatial frequencies), which reduced activity of parvocellular RGCs with smaller/slower axons. The blurred PERG latency was shorter than baseline by 2.9 ms (P = 0.01). CONCLUSIONS PERG latency is shortened in both eyes of MS patients with recovered unilateral ON, suggesting relative dysfunction of RGCs with slower axons and sparing of RGCs with faster axons. SIGNIFICANCE Assessment of PERG latency in MS and ON may help identifying and monitoring RGC dysfunction. PERG latency shortening in FE suggests primary retinopathy in MS.
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Bach M, Cuno AK, Hoffmann MB. Retinal conduction speed analysis reveals different origins of the P50 and N95 components of the (multifocal) pattern electroretinogram. Exp Eye Res 2018; 169:48-53. [PMID: 29374551 DOI: 10.1016/j.exer.2018.01.021] [Citation(s) in RCA: 16] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/20/2017] [Revised: 01/04/2018] [Accepted: 01/21/2018] [Indexed: 11/26/2022]
Abstract
The pattern electroretinogram (PERG), an indicator of retinal ganglion cell (RGC) function, comprises a P50 and an N95 component. We addressed the question of whether the N95 originates, like the P50, from the RGC bodies or from the change of axon orientation at the optic nerve head (ONH). Thus, we recorded multifocal PERGs for 36 retinal locations in 21 participants. Second-order kernel responses were analyzed for the dependence of peak time topography on retinal fiber lengths to the ONH separately for the positive and negative excursions. We found that peak times were longer for macular [P1 (P50-like): 50 ms; N2 (N95-like): 76)] than for peripheral responses [P1: 43; N2: 66]. For the N2 another factor was necessary to explain the variability: The time difference (deltaT: N2 minus P1) was found to be proportional to fiber length from ganglion cell body to the ONH. We calculated retinal fiber length using an analytical function by Jansonius et al. (2009, 2012) and found that a linear model with factors eccentricity and fiber length explained 82% of the total N2 time variance (p«0.001). The conduction speeds of the retinal axons were estimated from deltaT to range from 0.5 to 3.0 m/s for parafovea and periphery, respectively. The dependence of deltaT on the distance from ganglion cell body to the ONH suggests that the N2 originates at the ONH rather than at the ganglion cell body. While the multifocal N2 peaks earlier (≈76 ms) than the non-multifocal PERG-N95 (≈95 ms), considerations of high-pass filtering and frequency dependence of the mfPERG-N2 suggest that the source separation (P50 = ganglion cell body vs. N95 = ONH) also holds for the non-multifocal PERG.
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Affiliation(s)
- Michael Bach
- University Eye Center, Medical Center - University of Freiburg, Germany; Faculty of Medicine, University of Freiburg, Germany.
| | - Anne-Kathrin Cuno
- Visual Processing Laboratory, Universitäts-Augenklinik, Magdeburg, Germany
| | - Michael B Hoffmann
- Visual Processing Laboratory, Universitäts-Augenklinik, Magdeburg, Germany; Center for Behavioural Brain Sciences, Magdeburg, Germany
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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] [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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Electrophysiology of Olfactory and Optic Nerve in Outpatient and Intraoperative Settings. J Clin Neurophysiol 2018; 35:3-10. [PMID: 29300714 DOI: 10.1097/wnp.0000000000000416] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/25/2022] Open
Abstract
Evoked potentials are time-locked electrophysiologic potentials recorded in response to standardized stimuli using scalp electrodes. These responses provide good temporal resolution and have been used in various clinical and intraoperative settings. Olfactory evoked potentials (OEPs) may be used as an adjunct tool in identifying patients of Parkinson disease and Alzheimer dementia. In clinical practice, visual evoked potentials (VEPs) are particularly useful in identifying subclinical cases of optic neuritis and in treatment surveillance. In recent times, pattern electroretinograms and photopic negative response have been gaining attention in identifying glaucoma suspects. During surgical manipulation, there is a risk of damage to optic or olfactory nerve. Intraoperative neurophysiologic monitoring can provide information regarding the integrity of olfactory or visual pathway. OEPs and VEPs, however, show high degree of variability and are not reliable tools because the responses are extremely susceptible to volatile anesthetic agents. Newer techniques that could possibly circumvent these drawbacks have been developed but are not used extensively. In this article, we briefly review the available techniques to obtain OEPs and VEPs, diagnostic applications, the utility of intraoperative monitoring, the limitations of the current techniques, and the future directions for research.
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Electroretinography in idiopathic intracranial hypertension: comparison of the pattern ERG and the photopic negative response. Doc Ophthalmol 2017; 136:45-55. [PMID: 29139045 DOI: 10.1007/s10633-017-9620-z] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/20/2017] [Accepted: 11/02/2017] [Indexed: 10/18/2022]
Abstract
PURPOSE To evaluate the relationship between electrophysiological measures of retinal ganglion cell (RGC) function in patients who have idiopathic intracranial hypertension (IIH). METHODS The pattern electroretinogram (pERG) and photopic negative response (PhNR) were recorded from 11 IIH patients and 11 age-similar controls. The pERG was elicited by a contrast-reversing checkerboard. The PhNR, a slow negative component following the flash ERG b-wave, was recorded in response to a long-wavelength flash presented against a short-wavelength adapting field. The PhNR was elicited using full-field (ffPhNR) and focal macular (fPhNR) stimuli. Additionally, Humphrey visual field mean deviation (HVF MD) was measured and ganglion cell complex volume (GCCV) was obtained by optical coherence tomography. RESULTS The ffPhNR, fPhNR, and pERG amplitudes were outside of the normal range in 45, 9, and 45% of IIH patients, respectively. However, only mean ffPhNR amplitude was reduced significantly in the patients compared to controls (p < 0.01). The pERG amplitude correlated significantly with HVF MD and GCCV (both r > 0.65, p < 0.05). There were associations between ffPhNR amplitude and HVF MD (r = 0.58, p = 0.06) and with GCCV (r = 0.52, p = 0.10), but these did not reach statistical significance. fPhNR amplitude was not correlated significantly with HVF MD or GCCV (both r < 0.40, p > 0.20). CONCLUSIONS Although the fPhNR is generally normal in IIH, other electrophysiological measures of RGC function, the ffPhNR and pERG, are abnormal in some patients. These measures provide complementary information regarding RGC dysfunction in these individuals.
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Pojda-Wilczek D, Wycisło-Gawron P. The Effect of a Decrease in Intraocular Pressure on Optic Nerve Function in Patients with Optic Nerve Drusen. Ophthalmic Res 2017; 61:153-158. [PMID: 29084401 DOI: 10.1159/000481534] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/10/2017] [Accepted: 09/12/2017] [Indexed: 11/19/2022]
Abstract
PURPOSE The aim of the study was to compare optic nerve function in eyes with brinzolamide-reduced intraocular pressure (IOP) and the fellow eyes of patients with optic disk drusen (ODD). METHODS The study comprised 34 patients with bilateral ODD but no signs of any other ocular disease. The eyes with more advanced optic neuropathy were selected for treatment with an IOP-lowering drug, carbonic anhydrase inhibitor (brinzolamide); the fellow eyes served as the control. Static perimetry, pattern electroretinography (PERG), pattern visual-evoked potentials (PVEP), and retinal nerve fiber layer (RNFL) thickness were analyzed. The observation period was 12 months. RESULTS The eyes with brinzolamide-reduced IOP exhibited a statistically significant decrease in the mean defect index of static visual field (p = 0.03), an increase in PERG N95 amplitude (from 2.94 to 4.41 µV; p = 0.0047), and RNFL thickness stabilization. A statistically significant decrease in RNFL thickness (from 83.21 to 79.85 µm; p = 0.0017) was found in the control eyes. CONCLUSIONS A decrease in IOP in eyes with ODD results in improvement of retinal ganglion cell function and delays the progression of optic neuropathy. PERG should be performed in patients with ODD as it is a sensitive test for monitoring optic neuropathy.
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Affiliation(s)
- Dorota Pojda-Wilczek
- Department of Ophthalmology, School of Medicine in Katowice, Medical University of Silesia, Katowice, Poland
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Monsalve P, Triolo G, Toft-Nielsen J, Bohorquez J, Henderson AD, Delgado R, Miskiel E, Ozdamar O, Feuer WJ, Porciatti V. Next Generation PERG Method: Expanding the Response Dynamic Range and Capturing Response Adaptation. Transl Vis Sci Technol 2017; 6:5. [PMID: 28553559 PMCID: PMC5444497 DOI: 10.1167/tvst.6.3.5] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/23/2016] [Accepted: 03/27/2017] [Indexed: 11/25/2022] Open
Abstract
Purpose To compare a new method for steady-state pattern electroretinogram (PERGx) with a validated method (PERGLA) in normal controls and in patients with optic neuropathy. Methods PERGx and PERGLA were recorded in a mixed population (n = 33, 66 eyes) of younger controls (C1; n = 10, age 38 ± 8.3 years), older controls (C2; n = 11, 57.9 ± 8.09 years), patients with early manifest glaucoma (G; n = 7, 65.7 ±11.6 years), and patients with nonarteritic ischemic optic neuropathy (N; n = 5, mean age 59.4 ± 8.6 years). The PERGx stimulus was a black-white horizontal grating generated on a 14 × 14 cm LED display (1.6 cycles/deg, 15.63 reversals/s, 98% contrast, 800 cd/m2 mean luminance, 25° field). PERGx signal and noise were averaged over 1024 epochs (∼2 minutes) and Fourier analyzed to retrieve amplitude and phase. Partial averages (16 successive samples of 64 epochs each) were also analyzed to quantify progressive changes over recording time (adaptation). Results PERGLA and PERGx amplitudes and latencies were correlated (Amplitude R2 = 0.59, Latency R2 = 0.39, both P < 0.0001) and were similarly altered in disease. Compared to PERGLA, however, PERGx had shorter (16 ms) latency, higher (1.39×) amplitude, lower (0.37×) noise, and higher (4.2×) signal-to-noise ratio. PERGx displayed marked amplitude adaptation in C1 and C2 groups and no significant adaptation in G and N groups. Conclusions The PERGx high signal-to-noise ratio may allow meaningful recording in advanced stages of optic nerve disorders. In addition, it quantifies response adaptation, which may be selectively altered in glaucoma and optic neuropathy. Translational Relevance A new PERG method with increased dynamic range allows recording of retinal ganglion cell function in advanced stages of optic nerve disorders. It also quantifies the response decline during the test, an autoregulatory adaptation to metabolic challenge that decreases with age and presence of disease.
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Affiliation(s)
- Pedro Monsalve
- Bascom Palmer Eye Institute, University of Miami Miller School of Medicine, Miami, FL, USA
| | - Giacinto Triolo
- Bascom Palmer Eye Institute, University of Miami Miller School of Medicine, Miami, FL, USA
| | | | - Jorge Bohorquez
- Department of Biomedical Engineering, University of Miami, Miami, FL, USA
| | | | | | | | - Ozcan Ozdamar
- Department of Biomedical Engineering, University of Miami, Miami, FL, USA
| | - William J Feuer
- Bascom Palmer Eye Institute, University of Miami Miller School of Medicine, Miami, FL, USA
| | - Vittorio Porciatti
- Bascom Palmer Eye Institute, University of Miami Miller School of Medicine, Miami, FL, USA
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