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Contrast and spatial frequency modulation for diagnosis of amblyopia: An electrophysiological approach

PURPOSE: To evaluate the diagnostic value of visual evoked potentials (VEPs) and to find out which test setting has the most sensitivity and specificity for amblyopia diagnosis. METHODS: Thirty-three adult anisometropic amblyopes were intended in this study and were tested for visual evoked potentia...

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Autores principales: Mohammadi, Alireza, Hashemi, Hassan, Mirzajani, Ali, Yekta, Abbasali, jafarzadehpur, Ebrahim, Valadkhan, Mehrnaz, Khabazkhoob, Mehdi
Formato: Online Artículo Texto
Lenguaje:English
Publicado: Elsevier 2018
Materias:
Acceso en línea:https://www.ncbi.nlm.nih.gov/pmc/articles/PMC6407155/
https://www.ncbi.nlm.nih.gov/pubmed/30899850
http://dx.doi.org/10.1016/j.joco.2018.09.010
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author Mohammadi, Alireza
Hashemi, Hassan
Mirzajani, Ali
Yekta, Abbasali
jafarzadehpur, Ebrahim
Valadkhan, Mehrnaz
Khabazkhoob, Mehdi
author_facet Mohammadi, Alireza
Hashemi, Hassan
Mirzajani, Ali
Yekta, Abbasali
jafarzadehpur, Ebrahim
Valadkhan, Mehrnaz
Khabazkhoob, Mehdi
author_sort Mohammadi, Alireza
collection PubMed
description PURPOSE: To evaluate the diagnostic value of visual evoked potentials (VEPs) and to find out which test setting has the most sensitivity and specificity for amblyopia diagnosis. METHODS: Thirty-three adult anisometropic amblyopes were intended in this study and were tested for visual evoked potentials with different stimulus conditions including three spatial frequencies [1, 2, and 4-cycles-per-degree (cpd)] at four contrast levels (100, 50, 25, and 5%). We also tested psychophysical contrast sensitivity and compared the results with electrophysiological ones. We plotted Receiver Operating Characteristic (ROC) curve for each VEP recording and psychophysical contrast sensitivity to evaluate the area under the curve, sensitivity, specificity, and cut-point value of each test stimulus for detecting amblyopic eyes. RESULTS: Thirty-three amblyopic and 33 non-amblyopic eyes were examined for psychophysical contrast sensitivity and VEPs. Area under the ROC curve (AURC) findings showed that VEP with different stimulus settings can significantly detect amblyopic eyes, as well as psychophysical contrast sensitivity test. We found that P100 amplitudes had the largest AURC in response to stimuli of 2-cpd spatial frequency at 50 (P < 0.001) and 25% (P < 0.001) contrast levels, respectively. Cut-off amplitudes for these stimuli were 8.65 and 4.50 μV, which had a sensitivity of 0.758 and 0.697 and a specificity of 0.788 and 0.848, respectively. The sensitivity and specificity of VEP P100 amplitude in response to the stimuli with 2 cpd spatial frequency and 50 and 25% contrast were greater than the findings obtained from psychophysical contrast sensitivity test. CONCLUSION: According to our findings, assessment of VEP amplitudes in response to stimuli of 2-cpd spatial frequency at 50 and 25% contrast levels can best detect amblyopia with highest sensitivity and specificity and thus, are the protocols of choice for detection of amblyopic eyes.
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spelling pubmed-64071552019-03-21 Contrast and spatial frequency modulation for diagnosis of amblyopia: An electrophysiological approach Mohammadi, Alireza Hashemi, Hassan Mirzajani, Ali Yekta, Abbasali jafarzadehpur, Ebrahim Valadkhan, Mehrnaz Khabazkhoob, Mehdi J Curr Ophthalmol Article PURPOSE: To evaluate the diagnostic value of visual evoked potentials (VEPs) and to find out which test setting has the most sensitivity and specificity for amblyopia diagnosis. METHODS: Thirty-three adult anisometropic amblyopes were intended in this study and were tested for visual evoked potentials with different stimulus conditions including three spatial frequencies [1, 2, and 4-cycles-per-degree (cpd)] at four contrast levels (100, 50, 25, and 5%). We also tested psychophysical contrast sensitivity and compared the results with electrophysiological ones. We plotted Receiver Operating Characteristic (ROC) curve for each VEP recording and psychophysical contrast sensitivity to evaluate the area under the curve, sensitivity, specificity, and cut-point value of each test stimulus for detecting amblyopic eyes. RESULTS: Thirty-three amblyopic and 33 non-amblyopic eyes were examined for psychophysical contrast sensitivity and VEPs. Area under the ROC curve (AURC) findings showed that VEP with different stimulus settings can significantly detect amblyopic eyes, as well as psychophysical contrast sensitivity test. We found that P100 amplitudes had the largest AURC in response to stimuli of 2-cpd spatial frequency at 50 (P < 0.001) and 25% (P < 0.001) contrast levels, respectively. Cut-off amplitudes for these stimuli were 8.65 and 4.50 μV, which had a sensitivity of 0.758 and 0.697 and a specificity of 0.788 and 0.848, respectively. The sensitivity and specificity of VEP P100 amplitude in response to the stimuli with 2 cpd spatial frequency and 50 and 25% contrast were greater than the findings obtained from psychophysical contrast sensitivity test. CONCLUSION: According to our findings, assessment of VEP amplitudes in response to stimuli of 2-cpd spatial frequency at 50 and 25% contrast levels can best detect amblyopia with highest sensitivity and specificity and thus, are the protocols of choice for detection of amblyopic eyes. Elsevier 2018-11-01 /pmc/articles/PMC6407155/ /pubmed/30899850 http://dx.doi.org/10.1016/j.joco.2018.09.010 Text en © 2019 Iranian Society of Ophthalmology. Production and hosting by Elsevier B.V. http://creativecommons.org/licenses/by-nc-nd/4.0/ This is an open access article under the CC BY-NC-ND license (http://creativecommons.org/licenses/by-nc-nd/4.0/).
spellingShingle Article
Mohammadi, Alireza
Hashemi, Hassan
Mirzajani, Ali
Yekta, Abbasali
jafarzadehpur, Ebrahim
Valadkhan, Mehrnaz
Khabazkhoob, Mehdi
Contrast and spatial frequency modulation for diagnosis of amblyopia: An electrophysiological approach
title Contrast and spatial frequency modulation for diagnosis of amblyopia: An electrophysiological approach
title_full Contrast and spatial frequency modulation for diagnosis of amblyopia: An electrophysiological approach
title_fullStr Contrast and spatial frequency modulation for diagnosis of amblyopia: An electrophysiological approach
title_full_unstemmed Contrast and spatial frequency modulation for diagnosis of amblyopia: An electrophysiological approach
title_short Contrast and spatial frequency modulation for diagnosis of amblyopia: An electrophysiological approach
title_sort contrast and spatial frequency modulation for diagnosis of amblyopia: an electrophysiological approach
topic Article
url https://www.ncbi.nlm.nih.gov/pmc/articles/PMC6407155/
https://www.ncbi.nlm.nih.gov/pubmed/30899850
http://dx.doi.org/10.1016/j.joco.2018.09.010
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