PT  - JOURNAL ARTICLE
AU  - R S Behbehani
AU  - E L Affel
AU  - R C Sergott
AU  - P J Savino
TI  - Multifocal ERG in ethambutol associated visual loss
AID  - 10.1136/bjo.2004.065656
DP  - 2005 Aug 01
TA  - British Journal of Ophthalmology
PG  - 976--982
VI  - 89
IP  - 8
4099  - http://bjo.bmj.com/content/89/8/976.short
4100  - http://bjo.bmj.com/content/89/8/976.full
SO  - Br J Ophthalmol2005 Aug 01; 89
AB  - Aim: To determine the anatomical site and extent of electrophysiological dysfunction in patients with ethambutol associated visual loss. Methods: A comparative case series. Four patients with ethambutol associated visual loss underwent multifocal electroretinography (mERG). Two patients had advanced visual loss while two had early signs of toxicity. The N1-P1, N1, P1 amplitudes, N1, and P1 latencies were compared to 10 age and sex matched controls. Results: mERG abnormalities were detected in the ethambutol treated patients. The N1 amplitude was significantly lower in the ethambutol treated patients than in the control group. Conclusion: Ethambutol is possibly toxic to the retina, and not only the optic nerve. The multifocal ERG may be of value to diagnose and monitor patients taking ethambutol.