Visual Function Test for Early Detection of Ethambutol-Induced Ocular Toxicity.
10.3341/jkos.2012.53.5.694
- Author:
Jae Keun CHUNG
1
;
Yong Beom PARK
;
Sung Pyo PARK
Author Information
1. Department of Ophthalmology, Hallym University Kangdong Sacred Heart Hospital, Hallym University College of Medicine, Seoul, Korea. sungpyo@hananet.net
- Publication Type:Original Article
- Keywords:
Early detection;
Ethambutol;
Ocular toxicity;
Visual evoked potential
- MeSH:
Color Vision;
Contrast Sensitivity;
Ethambutol;
Evoked Potentials;
Evoked Potentials, Visual;
Eye;
Humans;
Nerve Fibers;
Prospective Studies;
Retinaldehyde;
Tomography, Optical Coherence;
Visual Acuity;
Visual Fields
- From:Journal of the Korean Ophthalmological Society
2012;53(5):694-699
- CountryRepublic of Korea
- Language:Korean
-
Abstract:
PURPOSE: The purpose of the present study was to investigate various visual function tests for early detection of ethambutol-induced ocular toxicity. METHODS: A prospective study of 20 eyes of 10 patients being treated with ethambutol was conducted. Visual acuity, visual field, color vision, fundus examination, contrast sensitivity, optical coherence tomography (OCT), and pattern-visual evoked potential (VEP) were assessed. Examinations were performed prior to therapy and every month for 5 months after treatment. VEP was performed every other month. The mean values of each parameter at each month were compared with the baseline examination and a p-value of <0.05 was considered significant. In addition, a greater than 2 standard deviation (SD) change in each parameter from the mean values at baseline was considered as an ocular toxicity induced change in each individual eye. RESULTS: On OCT, a significant increase of the average retinal nerve fiber layer thickness was detected after 4 months of therapy. VEP showed an increased mean latency of the P100 wave after 2 and 4 months of therapy. However, a greater than 2 SD change from the mean values of the baseline was not observed on OCT, while 30% (6/20) of the eyes showed more than a 2 SD increase in VEP latency. Visual acuity, color vision, fundus, contrast sensitivity, and visual field were not affected in any patients. CONCLUSIONS: The authors of the present study consider VEP as a sensitive test to detect early toxicity of ethambutol. VEP can be helpful in identifying subclinical ocular toxicity, especially in the high-risk patients.
