Abstract: Objective To study the clinical features of ethambutol optic neuropathy (EON). Design Retrospective case series. Participants 17 patients diagnosed as EON in PLA General Hospital. Method General condition, clinical characteristics, and treatment outcome of all 17 patients based on medical records were analyzed. Main Outcome Measures Best corrected visual acuity, visual field, color vision, color of optic disc. Results The average duration of ethambutol use is (8.0±4.0) months, and the average dosage is (166.8±82.9) g. Both eyes were affected in all patients. 28 eyes (82.4%) were characterized with chronic, progressive, painless vision loss. The mean best corrected visual acuity was (0.12±0.09) at first visit. 26 eyes (76.4%) had optic disc color change. 23 eyes (67.7%) showed central scotoma of visual field. 20 eyes (58.8%) manifested anerythrochloropsia. Abnormal signals of optic chiasma were not detected on magnetic resonance imaging in all the 17 cases. The best corrected visual acuity was raised to (0.34±0.15) in the last follow-up (average 8.6±3.8 months) after oral mecobalamine. Conclusion EON affects both eyes, manifested with chronic, progressive vision loss. It mainly implicates fasciculus macula papillaris and the visual impairment is reversible or partially reversible. (Ophthalmol CHN, 2014, 23: 43-46)

Key words: ethambutol, optic neuropathy