CORE
🇺🇦
make metadata, not war
Services
Services overview
Explore all CORE services
Access to raw data
API
Dataset
FastSync
Content discovery
Recommender
Discovery
OAI identifiers
OAI Resolver
Managing content
Dashboard
Bespoke contracts
Consultancy services
Support us
Support us
Membership
Sponsorship
Community governance
Advisory Board
Board of supporters
Research network
About
About us
Our mission
Team
Blog
FAQs
Contact us
Contrast and spatial frequency modulation for diagnosis of amblyopia: An electrophysiological approach
Authors
H. Hashemi
E. jafarzadehpur
+5 more
M. Khabazkhoob
A. Mirzajani
A. Mohammadi
M. Valadkhan
A. Yekta
Publication date
1 January 2019
Publisher
Abstract
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. © 2018 Iranian Society of Ophthalmolog
Similar works
Full text
Open in the Core reader
Download PDF
Available Versions
eprints Iran University of Medical Sciences
See this paper in CORE
Go to the repository landing page
Download from data provider
oai:eprints.iums.ac.ir:14941
Last time updated on 01/12/2020