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Estimation of Visual Acuity after Recovery from Different Degrees of Ocular Trauma Using Pattern Visual Evoked
Hong-Xia Hao1, Jie-Min Chen1, Xiao-Ying Yu1
1Shanghai Key Laboratory of Forensic Medicine, Key Laboratory of Forensic Science, Ministry of Justice, Shanghai Forensic Service Platform, Academy of Forensic Science, Shanghai 200063, China.
Fa Yi Xue Za Zhi
|February 24, 2025
Summary
Pattern visual evoked potential (PVEP) can help assess visual function in ocular trauma patients. Abnormal P100 amplitudes in PVEP correlate with the severity of eye injury, aiding visual evaluation.
Area of Science:
- Ophthalmology
- Neuroscience
- Visual electrophysiology
Background:
- Complex ocular trauma presents challenges in visual assessment.
- Visual evoked potential (VEP) offers a method for evaluating visual pathway function.
Purpose of the Study:
- To investigate the characteristics of pattern visual evoked potential (PVEP) in patients with varying degrees of ocular trauma.
- To establish PVEP as a reference for visual assessment in complex ocular trauma.
Main Methods:
- 231 patients with monocular visual impairment were classified into three groups based on ocular trauma severity (A, B, C).
- Patients were also graded by best-corrected visual acuity (BCVA) post-recovery (Grades I-IV).
- PVEP P100 wave amplitude and peak time were recorded at 1° and 15' spatial frequencies for correlation analysis.
Main Results:
- Significant differences in P100 amplitude were observed between severe trauma (Group C) and milder trauma groups (A and B).
- Abnormal P100 amplitudes, particularly at 15' spatial frequency, were more frequent in Group C.
- Significant differences in P100 amplitudes were found between injured and healthy eyes in lower visual acuity grades (I and II).
Conclusions:
- PVEP effectively distinguishes between severe (Group C) and less severe ocular trauma (Groups A and B).
- PVEP cannot differentiate between mild trauma groups (A and B) at tested spatial frequencies.
- Abnormalities in P100 amplitudes provide a basis for evaluating visual function in ocular trauma patients.
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