1
|
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.
Collapse
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
| |
Collapse
|
2
|
Miura G. Visual Evoked Potentials for the Detection of Diabetic Retinal Neuropathy. Int J Mol Sci 2023; 24:ijms24087361. [PMID: 37108524 PMCID: PMC10138821 DOI: 10.3390/ijms24087361] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/02/2023] [Revised: 04/14/2023] [Accepted: 04/16/2023] [Indexed: 04/29/2023] Open
Abstract
Visual evoked potentials (VEP) are visually evoked signals that extract electroencephalographic activity in the visual cortex that can detect retinal ganglion cells, optic nerves, chiasmal and retrochiasmal dysfunction, including optic radiations, and the occipital cortex. Because diabetes causes diabetic retinopathy due to microangiopathy and neuropathy due to metabolic abnormalities and intraneural blood flow disorders, assessment of diabetic visual pathway impairment using VEP has been attempted. In this review, evidence on the attempts to assess the visual pathway dysfunction due to abnormal blood glucose levels using VEP is presented. Previous studies have provided significant evidence that VEP can functionally detect antecedent neuropathy before fundus examination. The detailed correlations between VEP waveforms and disease duration, HbA1c, glycemic control, and short-term increases and decreases in blood glucose levels are evaluated. VEP may be useful for predicting postoperative prognosis and evaluating visual function before surgery for diabetic retinopathy. Further controlled studies with larger cohorts are needed to establish a more detailed relationship between diabetes mellitus and VEP.
Collapse
Affiliation(s)
- Gen Miura
- Department of Ophthalmology and Visual Science, Chiba University Graduate School of Medicine, Inohana 1-8-1, Chuo-ku, Chiba 260-8677, Japan
| |
Collapse
|
3
|
Marmoy OR, Viswanathan S. Clinical electrophysiology of the optic nerve and retinal ganglion cells. Eye (Lond) 2021; 35:2386-2405. [PMID: 34117382 PMCID: PMC8377055 DOI: 10.1038/s41433-021-01614-x] [Citation(s) in RCA: 6] [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: 03/17/2021] [Revised: 05/11/2021] [Accepted: 05/19/2021] [Indexed: 12/28/2022] Open
Abstract
Clinical electrophysiological assessment of optic nerve and retinal ganglion cell function can be performed using the Pattern Electroretinogram (PERG), Visual Evoked Potential (VEP) and the Photopic Negative Response (PhNR) amongst other more specialised techniques. In this review, we describe these electrophysiological techniques and their application in diseases affecting the optic nerve and retinal ganglion cells with the exception of glaucoma. The disease groups discussed include hereditary, compressive, toxic/nutritional, traumatic, vascular, inflammatory and intracranial causes for optic nerve or retinal ganglion cell dysfunction. The benefits of objective, electrophysiological measurement of the retinal ganglion cells and optic nerve are discussed, as are their applications in clinical diagnosis of disease, determining prognosis, monitoring progression and response to novel therapies.
Collapse
Affiliation(s)
- Oliver R Marmoy
- Clinical and Academic Department of Ophthalmology, Great Ormond Street Hospital for Children, London, UK.
- UCL-GOS Institute for Child Health, University College London, London, UK.
- Manchester Metropolitan University, Manchester, UK.
| | | |
Collapse
|
4
|
Martins ICVS, Brasil A, Miquilini L, Goulart PRK, Herculano AM, Silveira LCL, Souza GS. Spatial frequency selectivity of the human visual cortex estimated with pseudo-random visual evoked cortical potential (VECP). Vision Res 2019; 165:13-21. [PMID: 31610286 DOI: 10.1016/j.visres.2019.09.004] [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: 12/08/2018] [Revised: 06/20/2019] [Accepted: 09/18/2019] [Indexed: 10/25/2022]
Abstract
Single-cell recordings in the primary visual cortex (V1) show neurons with spatial frequency (SF) tuning, which had different responses to chromatic and luminance stimuli. Visually evoked cortical potential (VECP) investigations have reported different spatial profiles. The current study aimed to investigate the spatial selectivity of V1 to simultaneous stimulus of chromatic and luminance contrasts. Compound stimuli temporally driven by m-sequences at 8 SFs were utilized to generate VECP records from thirty subjects (14 trichromats and 16 colorblind subjects). We extracted the second-order kernel, first and second slices (K2.1 and K2.2, respectively). Optimal SF, SF bandwidth, and high SF cut-off were estimated from the best-fitted functions to the VECP amplitude vs SF. For trichromats, K2.1 waveforms had a negative component (N1 K2.1) at 100 ms followed by a positive component (P1 K2.1). K2.2 waveforms also had a negative component (N1 K2.2) at 100 ms followed by a positive deflection (P1 K2.2). SF tuning of N1 K2.1 and N1 K2.2 had a band-pass profile, while the P1 K2.1 was low-pass tuned. P1 K2.1 optimal SF differed significantly from both other negative responses and from P1 K2.2. We found differences in the optimal SF, SF tuning and high SF cut-off among the VECP components. Dichromats had little or no response for all stimulus conditions. The absence of the responses in dichromats, the similarity between the high SF cut-off of the pseudorandom VECPs and psychophysical chromatic visual acuity, and presence of multiple SF tunings suggested that pseudorandom VECPs represented the activity of cells that responded preferentially to the chromatic component of the compound stimuli.
Collapse
Affiliation(s)
- Isabelle Christine V S Martins
- Instituto de Ciências Biológicas, Universidade Federal do Pará, Belém, Pará, Brazil; Universidade do Ceuma, São Luís, Maranhão, Brazil
| | - Alódia Brasil
- Núcleo de Medicina Tropical, Universidade Federal do Pará, Belém, Pará, Brazil; Universidade do Ceuma, São Luís, Maranhão, Brazil
| | - Letícia Miquilini
- Instituto de Ciências Biológicas, Universidade Federal do Pará, Belém, Pará, Brazil; Núcleo de Teoria e Pesquisa do Comportamento, Universidade Federal do Pará, Brazil; Universidade do Ceuma, São Luís, Maranhão, Brazil
| | - Paulo Roney Kilpp Goulart
- Núcleo de Teoria e Pesquisa do Comportamento, Universidade Federal do Pará, Brazil; Universidade do Ceuma, São Luís, Maranhão, Brazil
| | - Anderson Manoel Herculano
- Instituto de Ciências Biológicas, Universidade Federal do Pará, Belém, Pará, Brazil; Universidade do Ceuma, São Luís, Maranhão, Brazil
| | - Luiz Carlos L Silveira
- Instituto de Ciências Biológicas, Universidade Federal do Pará, Belém, Pará, Brazil; Núcleo de Medicina Tropical, Universidade Federal do Pará, Belém, Pará, Brazil; Núcleo de Teoria e Pesquisa do Comportamento, Universidade Federal do Pará, Brazil; Universidade do Ceuma, São Luís, Maranhão, Brazil
| | - Givago S Souza
- Instituto de Ciências Biológicas, Universidade Federal do Pará, Belém, Pará, Brazil; Núcleo de Medicina Tropical, Universidade Federal do Pará, Belém, Pará, Brazil; Universidade do Ceuma, São Luís, Maranhão, Brazil.
| |
Collapse
|
5
|
Salomão RC, Martins ICVDS, Risuenho BBO, Guimarães DL, Silveira LCL, Ventura DF, Souza GS. Visual evoked cortical potential elicited by pseudoisochromatic stimulus. Doc Ophthalmol 2019; 138:43-54. [PMID: 30617670 DOI: 10.1007/s10633-018-09669-0] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/16/2017] [Accepted: 12/31/2018] [Indexed: 11/25/2022]
Abstract
PURPOSE Visual evoked cortical potentials (VECPs) are useful for investigating the mechanisms and dysfunctions of color vision. Chromatic sinusoidal gratings are generally used to elicit VECPs, but they require long psychophysical measurements to match the perceptual luminance between their stripes. An alternative method is to use pseudoisochromatic stimuli, which makes use of luminance noise to mask luminance clues and force the target perception to be dependent on chromatic contrast. In this study, we compared VECPs generated by sinusoidal gratings and pseudoisochromatic gratings. Contrary to chromatic sinusoidal gratings, pseudoisochromatic stimuli do not require the use of previous methods to find the equiluminance of the stimulus. METHODS Normal trichromats were recruited to be tested with red-green chromatic sinusoidal gratings and pseudoisochromatic gratings presented by pattern onset-offset and pattern reversal modes in five spatial frequencies. In addition, we also tested four different chromatic contrast pairs in pattern onset-offset mode presentation in five trichromats and one colorblind subject (deuteranope). RESULTS Pattern onset-offset VECPs elicited by sinusoidal gratings had a larger amplitude than those obtained with pseudoisochromatic stimuli, whereas pattern reversal VECPs elicited by pseudoisochromatic gratings had similar amplitudes compared to those elicited by sinusoidal gratings. We found no difference between the VECP amplitudes elicited by sinusoidal and pseudoisochromatic gratings containing different chromatic contrast. Color-blind subjects displayed absent or small responses to the stimuli. CONCLUSION Pseudoisochromatic stimulus can be an alternative stimulus to generate VECPs dominated by the chromatic mechanism.
Collapse
Affiliation(s)
- Railson Cruz Salomão
- Instituto de Ciências Biológicas, Universidade Federal do Pará, Belém, Pará, Brazil
- Núcleo de Medicina Tropical, Universidade Federal do Pará, Av Generalíssimo Deodoro 92, Umarizal, Belém, Pará, 66055240, Brazil
| | | | | | - Diego Leite Guimarães
- Núcleo de Medicina Tropical, Universidade Federal do Pará, Av Generalíssimo Deodoro 92, Umarizal, Belém, Pará, 66055240, Brazil
| | - Luiz Carlos Lima Silveira
- Instituto de Ciências Biológicas, Universidade Federal do Pará, Belém, Pará, Brazil
- Núcleo de Medicina Tropical, Universidade Federal do Pará, Av Generalíssimo Deodoro 92, Umarizal, Belém, Pará, 66055240, Brazil
- Universidade CEUMA, São Luiz, Maranhão, Brazil
| | | | - Givago Silva Souza
- Instituto de Ciências Biológicas, Universidade Federal do Pará, Belém, Pará, Brazil.
- Núcleo de Medicina Tropical, Universidade Federal do Pará, Av Generalíssimo Deodoro 92, Umarizal, Belém, Pará, 66055240, Brazil.
| |
Collapse
|