1
|
Bhatt Y, Hunt DM, Carvalho LS. The origins of the full-field flash electroretinogram b-wave. Front Mol Neurosci 2023; 16:1153934. [PMID: 37465364 PMCID: PMC10351385 DOI: 10.3389/fnmol.2023.1153934] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/30/2023] [Accepted: 06/12/2023] [Indexed: 07/20/2023] Open
Abstract
The electroretinogram (ERG) measures the electrical activity of retinal neurons and glial cells in response to a light stimulus. Amongst other techniques, clinicians utilize the ERG to diagnose various eye diseases, including inherited conditions such as cone-rod dystrophy, rod-cone dystrophy, retinitis pigmentosa and Usher syndrome, and to assess overall retinal health. An ERG measures the scotopic and photopic systems separately and mainly consists of an a-wave and a b-wave. The other major components of the dark-adapted ERG response include the oscillatory potentials, c-wave, and d-wave. The dark-adapted a-wave is the initial corneal negative wave that arises from the outer segments of the rod and cone photoreceptors hyperpolarizing in response to a light stimulus. This is followed by the slower, positive, and prolonged b-wave, whose origins remain elusive. Despite a large body of work, there remains controversy around the mechanisms involved in the generation of the b-wave. Several hypotheses attribute the origins of the b-wave to bipolar or Müller glial cells or a dual contribution from both cell types. This review will discuss the current hypothesis for the cellular origins of the dark-adapted ERG, with a focus on the b-wave.
Collapse
Affiliation(s)
- Yashvi Bhatt
- Centre for Ophthalmology and Visual Science, The University of Western Australia, Perth, WA, Australia
- Lions Eye Institute Ltd., Nedlands, WA, Australia
| | - David M. Hunt
- Centre for Ophthalmology and Visual Science, The University of Western Australia, Perth, WA, Australia
- Lions Eye Institute Ltd., Nedlands, WA, Australia
| | - Livia S. Carvalho
- Centre for Ophthalmology and Visual Science, The University of Western Australia, Perth, WA, Australia
- Lions Eye Institute Ltd., Nedlands, WA, Australia
| |
Collapse
|
2
|
Song MY, Kim US. Current usage of electrophysiological tests in a secondary referral hospital in Korea. Doc Ophthalmol 2022; 145:127-131. [PMID: 36006567 DOI: 10.1007/s10633-022-09894-8] [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: 01/18/2022] [Accepted: 08/09/2022] [Indexed: 11/03/2022]
Abstract
PURPOSE To investigate the current status of electrophysiological test use in ophthalmology. METHODS We analyzed 1057 electrophysiological tests conducted at Kim's Eye Hospital from January 1 to December 31, 2018. The included tests were electroretinogram (full-field, multifocal, and pattern ERG), electrooculogram (EOG), and visual evoked potential (pattern and flash VEP). To investigate the distribution of use of subspecialties, it was divided by subspecialties (retina, glaucoma, oculoplastic surgery, pediatric ophthalmology, neuro-ophthalmology, cornea, and external diseases). RESULTS The patients were aged 50.6 years on average and included 624 men and 433 women. Among the electrophysiological tests, VEP was the most common, with 567 cases (53.6%), followed by ERG with 311 cases (29.4%) and EOG with 98 cases (9.3%). Regarding the purpose of use, the objective of visual function evaluation was the highest at 56.3%, followed by the differential diagnosis of unknown causes (33.0%) and the confirmation of diagnoses (10.7%). Both VEP and ERG were used the most for visual function evaluation, and mfERG was most used for differential diagnosis of unknown etiology. Electrophysiological tests were most often used in the retina department, but VEPs were used in various fields such as neuro-ophthalmology, glaucoma, and oculoplastics. CONCLUSION Electrophysiological tests are used to objectively evaluate visual function or discriminate diseases of unknown causes and are used in various departments. Electrophysiology testing is expected to be an additional test to assess visual function.
Collapse
Affiliation(s)
| | - Ungsoo Samuel Kim
- Department of Ophthalmology, Chung-Ang University, Gwangmyeong Hospital, Deokan-ro 110, Gwangmyeong-si, Gyeonggi-do, 14353, Republic of Korea.
| |
Collapse
|
3
|
Yang JJ, Huang CH, Yang CH, Yang CM, Lin CW, Ho TC, Lin CP, Hsieh YT, Yeh PT, Lai TT, Chen PL, Chen TC. The Clinical Contribution of Full-Field Electroretinography and 8-Year Experiences of Application in a Tertiary Medical Center. J Pers Med 2021; 11:jpm11101022. [PMID: 34683163 PMCID: PMC8539721 DOI: 10.3390/jpm11101022] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/11/2021] [Revised: 10/05/2021] [Accepted: 10/09/2021] [Indexed: 12/15/2022] Open
Abstract
Electroretinography (ERG) is an important and well-established examination for retinal and visual pathway diseases. This study reviewed the medical records of patients who received full-field ERG (ffERG) at a single medical center between 2012 and 2019, which was an 8-year experience in the clinical contribution of ERG. Based on the indication for scheduling ffERG and the final diagnosis, patients could be classified into six groups: ‘retinal dystrophies’, ‘other retinal or macular diseases’, ‘optic neuropathies’, ‘visual complaints’, ‘systemic diseases’, and ‘others’. A total of 1921 full-field electroretinograms (ffERGs) (1655 patients) were included. The average number of ffERGs performed per year was 262 and the number of annual ffERGs was constant. The ‘retinal dystrophies’ group accounted for 36.5% of the studied population, followed by the ‘other retinal or macular diseases’ group (20.2%). The most common systemic disease was central nervous system disease. The rates of abnormal ffERGs in the ‘systemic diseases’, ‘optic neuropathies’, and ‘visual complaints’ groups were 27.3%, 22.6%, and 10.1%, respectively (p < 0.001). Higher rates were found in patients <20 years old in the ‘systemic diseases’ and ‘optic neuropathies’ groups; epilepsy and optic nerve atrophy were the most common diagnoses, respectively. In brief, by quantifying the functional response in the retina, ffERG is indispensable for diagnosis and prognosis in ophthalmologic and multidisciplinary practice.
Collapse
Affiliation(s)
- Jung-Je Yang
- Department of Medical Education, National Taiwan University Hospital, Taipei 10002, Taiwan;
| | - Chu-Hsuan Huang
- Department of Ophthalmology, Cathay General Hospital, Taipei 10002, Taiwan;
| | - Chang-Hao Yang
- Department of Ophthalmology, National Taiwan University Hospital, Taipei 10002, Taiwan; (C.-H.Y.); (C.-M.Y.); (C.-W.L.); (T.-C.H.); (C.-P.L.); (Y.-T.H.); (P.-T.Y.); (T.-T.L.)
- Department of Ophthalmology, College of Medicine, National Taiwan University, Taipei 10002, Taiwan
| | - Chung-May Yang
- Department of Ophthalmology, National Taiwan University Hospital, Taipei 10002, Taiwan; (C.-H.Y.); (C.-M.Y.); (C.-W.L.); (T.-C.H.); (C.-P.L.); (Y.-T.H.); (P.-T.Y.); (T.-T.L.)
- Department of Ophthalmology, College of Medicine, National Taiwan University, Taipei 10002, Taiwan
| | - Chao-Wen Lin
- Department of Ophthalmology, National Taiwan University Hospital, Taipei 10002, Taiwan; (C.-H.Y.); (C.-M.Y.); (C.-W.L.); (T.-C.H.); (C.-P.L.); (Y.-T.H.); (P.-T.Y.); (T.-T.L.)
| | - Tzyy-Chang Ho
- Department of Ophthalmology, National Taiwan University Hospital, Taipei 10002, Taiwan; (C.-H.Y.); (C.-M.Y.); (C.-W.L.); (T.-C.H.); (C.-P.L.); (Y.-T.H.); (P.-T.Y.); (T.-T.L.)
- Department of Ophthalmology, College of Medicine, National Taiwan University, Taipei 10002, Taiwan
| | - Chang-Ping Lin
- Department of Ophthalmology, National Taiwan University Hospital, Taipei 10002, Taiwan; (C.-H.Y.); (C.-M.Y.); (C.-W.L.); (T.-C.H.); (C.-P.L.); (Y.-T.H.); (P.-T.Y.); (T.-T.L.)
- Department of Ophthalmology, College of Medicine, National Taiwan University, Taipei 10002, Taiwan
| | - Yi-Ting Hsieh
- Department of Ophthalmology, National Taiwan University Hospital, Taipei 10002, Taiwan; (C.-H.Y.); (C.-M.Y.); (C.-W.L.); (T.-C.H.); (C.-P.L.); (Y.-T.H.); (P.-T.Y.); (T.-T.L.)
- Department of Ophthalmology, College of Medicine, National Taiwan University, Taipei 10002, Taiwan
| | - Po-Ting Yeh
- Department of Ophthalmology, National Taiwan University Hospital, Taipei 10002, Taiwan; (C.-H.Y.); (C.-M.Y.); (C.-W.L.); (T.-C.H.); (C.-P.L.); (Y.-T.H.); (P.-T.Y.); (T.-T.L.)
- Department of Ophthalmology, College of Medicine, National Taiwan University, Taipei 10002, Taiwan
| | - Tso-Ting Lai
- Department of Ophthalmology, National Taiwan University Hospital, Taipei 10002, Taiwan; (C.-H.Y.); (C.-M.Y.); (C.-W.L.); (T.-C.H.); (C.-P.L.); (Y.-T.H.); (P.-T.Y.); (T.-T.L.)
| | - Pei-Lung Chen
- Graduate Institute of Clinical Medicine, College of Medicine, National Taiwan University, Taipei 10002, Taiwan;
- Graduate Institute of Medical Genomics and Proteomics, College of Medicine, National Taiwan University, Taipei 10002, Taiwan
- Department of Medical Genetics, National Taiwan University Hospital, Taipei 10002, Taiwan
| | - Ta-Ching Chen
- Department of Ophthalmology, National Taiwan University Hospital, Taipei 10002, Taiwan; (C.-H.Y.); (C.-M.Y.); (C.-W.L.); (T.-C.H.); (C.-P.L.); (Y.-T.H.); (P.-T.Y.); (T.-T.L.)
- Graduate Institute of Clinical Medicine, College of Medicine, National Taiwan University, Taipei 10002, Taiwan;
- Correspondence: ; Tel.: +886-2-23123456 (ext. 63783)
| |
Collapse
|
4
|
Jauregui R, Cho GY, Takahashi VKL, Takiuti JT, Bassuk AG, Mahajan VB, Tsang SH. Caring for Hereditary Childhood Retinal Blindness. Asia Pac J Ophthalmol (Phila) 2018; 7:183-191. [PMID: 29536675 DOI: 10.22608/apo.201851] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022] Open
Abstract
Inherited retinal diseases (IRDs) are a major cause of incurable familial blindness in the Western world. In the pediatric population, IRDs are a major contributor to the 19 million children worldwide with visual impairment. Unfortunately, the road to the correct diagnosis is often complicated in the pediatric population, as typical diagnostic tools such as fundus examination, electrodiagnostic studies, and other imaging modalities may be difficult to perform in the pediatric patient. In this review, we describe the most significant IRDs with onset during the pediatric years (ie, before the age of 18). We describe the pathogenesis, clinical presentation, and potential treatment of these diseases. In addition, we advocate the use of a pedigree (family medical history), electroretinography, and genetic testing as the 3 most crucial tools for the correct diagnosis of IRDs in the pediatric population.
Collapse
Affiliation(s)
- Ruben Jauregui
- Department of Ophthalmology, Columbia University, New York, NY
- Jonas Children's Vision Care and Bernard & Shirlee Brown Glaucoma Laboratory, Department of Ophthalmology, Columbia University Medical Center, New York, NY
- Weill Cornell Medical College, New York, NY
| | - Galaxy Y Cho
- Department of Ophthalmology, Columbia University, New York, NY
- Jonas Children's Vision Care and Bernard & Shirlee Brown Glaucoma Laboratory, Department of Ophthalmology, Columbia University Medical Center, New York, NY
- Frank H. Netter MD School of Medicine, Quinnipiac University, North Haven, CT
| | - Vitor K L Takahashi
- Department of Ophthalmology, Columbia University, New York, NY
- Jonas Children's Vision Care and Bernard & Shirlee Brown Glaucoma Laboratory, Department of Ophthalmology, Columbia University Medical Center, New York, NY
- Department of Ophthalmology, Federal University of São Paulo, São Paulo, Brazil
| | - Julia T Takiuti
- Department of Ophthalmology, Columbia University, New York, NY
- Jonas Children's Vision Care and Bernard & Shirlee Brown Glaucoma Laboratory, Department of Ophthalmology, Columbia University Medical Center, New York, NY
- Division of Ophthalmology, University of São Paulo Medical School, São Paulo, Brazil
| | | | - Vinit B Mahajan
- Byers Eye Institute, Omics Laboratory, Department of Ophthalmology, Stanford University School of Medicine, Palo Alto, CA
- Palo Alto Veterans Administration, Palo Alto, CA
| | - Stephen H Tsang
- Department of Ophthalmology, Columbia University, New York, NY
- Department of Pathology & Cell Biology, Stem Cell Initiative (CSCI), Institute of Human Nutrition, College of Physicians and Surgeons, Columbia University, New York, NY
| |
Collapse
|
5
|
Panel-Based Clinical Genetic Testing in 85 Children with Inherited Retinal Disease. Ophthalmology 2017; 124:985-991. [PMID: 28341476 DOI: 10.1016/j.ophtha.2017.02.005] [Citation(s) in RCA: 39] [Impact Index Per Article: 5.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/15/2016] [Revised: 02/03/2017] [Accepted: 02/06/2017] [Indexed: 11/20/2022] Open
Abstract
PURPOSE To assess the clinical usefulness of genetic testing in a pediatric population with inherited retinal disease (IRD). DESIGN Single-center retrospective case series. PARTICIPANTS Eighty-five unrelated children with a diagnosis of isolated or syndromic IRD who were referred for clinical genetic testing between January 2014 and July 2016. METHODS Participants underwent a detailed ophthalmic examination, accompanied by electrodiagnostic testing (EDT) and dysmorphologic assessment where appropriate. Ocular and extraocular features were recorded using Human Phenotype Ontology terms. Subsequently, multigene panel testing (105 or 177 IRD-associated genes) was performed in an accredited diagnostic laboratory, followed by clinical variant interpretation. MAIN OUTCOME MEASURES Diagnostic yield and clinical usefulness of genetic testing. RESULTS Overall, 78.8% of patients (n = 67) received a probable molecular diagnosis; 7.5% (n = 5) of these had autosomal dominant disease, 25.4% (n = 17) had X-linked disease, and 67.2% (n = 45) had autosomal recessive disease. In a further 5.9% of patients (n = 5), a single heterozygous ABCA4 variant was identified; all these participants had a spectrum of clinical features consistent with ABCA4 retinopathy. Most participants (84.7%; n = 72) had undergone EDT and 81.9% (n = 59) of these patients received a probable molecular diagnosis. The genes most frequently mutated in the present cohort were CACNA1F and ABCA4, accounting for 14.9% (n = 10) and 11.9% (n = 8) of diagnoses respectively. Notably, in many cases, genetic testing helped to distinguish stationary from progressive IRD subtypes and to establish a precise diagnosis in a timely fashion. CONCLUSIONS Multigene panel testing pointed to a molecular diagnosis in 84.7% of children with IRD. The diagnostic yield in the study population was significantly higher compared with that in previously reported unselected IRD cohorts. Approaches similar to the one described herein are expected to become a standard component of care in pediatric ophthalmology. We propose the introduction of genetic testing early in the diagnostic pathway in children with clinical and/or electrophysiologic findings, suggestive of IRD.
Collapse
|
6
|
Tan ACS, Chen L, Png R, Chia A. The diagnosis and assessment of visual function in Singaporean children with electrophysiology: 10-year results. Doc Ophthalmol 2016; 132:189-99. [PMID: 27084553 DOI: 10.1007/s10633-016-9539-9] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/09/2015] [Accepted: 04/07/2016] [Indexed: 11/30/2022]
Abstract
PURPOSE To study the clinical use and efficacy of electrophysiology in children. METHODS This was a retrospective review of all children aged <16 years, who were referred to the Visual Electrophysiology Laboratory at the Singapore National Eye Center between 2003 and 2013. RESULTS A total of 586 children, median age 8 years (range 0.15-16), were referred for a variety of reasons including investigation of poor vision (40 %), suspected retinal disease or optic nerve/cortical dysfunction (17 %), nystagmus (13 %) and screening or monitoring of a variety of ocular or neurological conditions (12 %). The number of children with vision 6/15 or worse was 418 (71 %), and 103 (18 %) had vision 6/120 or worse in at least one eye. The most common pathology noted was retinal dystrophy or dysfunction (41 %) or optic nerve/cortical dysfunction (12 %). In 30 %, visual electrophysiology was within normal limits, and in 6 %, a conclusive diagnosis could not be obtained. CONCLUSION Electrophysiology testing played an important role in the assessment of children and added to the clinical management of the patient.
Collapse
Affiliation(s)
- Anna C S Tan
- Singapore National Eye Centre, 11 Third Hospital Avenue, Singapore, 168751, Singapore. .,Singapore Eye Research Institute, Singapore, Singapore.
| | - LiYu Chen
- Singapore National Eye Centre, 11 Third Hospital Avenue, Singapore, 168751, Singapore
| | - Rena Png
- Singapore National Eye Centre, 11 Third Hospital Avenue, Singapore, 168751, Singapore
| | - Audrey Chia
- Singapore National Eye Centre, 11 Third Hospital Avenue, Singapore, 168751, Singapore.,Singapore Eye Research Institute, Singapore, Singapore
| |
Collapse
|
7
|
Moschos MM, Gouliopoulos NS, Kalogeropoulos C. Electrophysiological examination in uveitis: a review of the literature. Clin Ophthalmol 2014; 8:199-214. [PMID: 24453476 PMCID: PMC3894140 DOI: 10.2147/opth.s54838] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/23/2022] Open
Abstract
Purpose Uveitis is the inflammation of the uveal tract, which usually also affects the retina and vitreous humor. The electrophysiological examination is an objective ocular examination that includes the electroretinogram, visual evoked potentials, the electrooculogram, the multifocal electroretinogram, and multifocal visual evoked potentials. Our aim is to review the literature of the use of the electrophysiological examination in cases of uveitis. Methods We performed a systematic search of the literature of published papers until October 2012 using the PubMed search engine. The key terms that were used were “uveitis”, “electrophysiological examination”, “electroretinogram”, “visual evoked potentials”, “electrooculogram”, “multifocal electroretinogram”, and “multifocal visual evoked potentials” in multiple combinations. To the best of our knowledge, this is the first review concerning the assessment of electrophysiology in uveitis. Results Our search of the literature demonstrated that the electrophysiological examination, mainly by means of electroretinogram, multifocal electroretinogram, and visual evoked potentials, is performed in several cases of uveitis for many purposes, including diagnosis and monitoring of disease progression and treatment efficacy. The electrophysiological examination is more useful in patients with multiple evanescent white dot syndrome, acute posterior multifocal placoid pigment epitheliopathy, birdshot chorioretinopathy, Vogt–Koyanagi–Harada disease, Adamantiades–Behçet disease, ocular syphilis, and Fuchs heterochromic cyclitis. Conclusion This review summarizes the use of the electrophysiological examination in uveitic patients and underlines its value as a useful tool in the objective assessment and the monitoring of the disease.
Collapse
Affiliation(s)
- Marilita M Moschos
- Laboratory of Electrophysiology, First Department of Ophthalmology, University of Athens, Athens, Greece
| | - Nikolaos S Gouliopoulos
- Laboratory of Electrophysiology, First Department of Ophthalmology, University of Athens, Athens, Greece
| | | |
Collapse
|