Berezina TL et al. – Short–term use of vigabatrin did not cause a decrease in visual acuity or significant peripheral visual field changes in cocaine abusers.Methods
- Cocaine addicts were randomized to receive vigabatrin 3000 mg/day, cumulative dose 218 g (n = 92), or placebo (n = 94) for 12 weeks.
- Subjects underwent examination of visual acuity (ETDRS) and peripheral visual field (PVF) by Humphrey Field Analyzer (HFA) 60-4 program before and after treatment.
- Reliable PVF tests (fixation loss, false positive, and false negative <33%) for 103 subjects were included for the analysis.
- The threshold visual sensitivity (TVS) was analyzed by points, rings and zones.
- Main outcome measures included visual acuity decrease by 15 letters and/or significant PVF alteration, defined as 5 or more visual field location points having greater than or equal to 15 dB reduction in TVS or decline (≥33% loss) in posttreatment TVS for 1 or more rings.
- Visual acuity decrease was detected in 1 eye of a subject receiving placebo and in none receiving vigabatrin.
- Posttreatment reduction in TVS more than 15 dB in 5 or more adjacent visual field location points combined with reduction in TVS greater than 33% in 1 or more of the rings was detected in 2 of 54 subjects (3.7%) from the vigabatrin group and in 1 of 49 subjects (2%) from the placebo group (P = .9, NS).
- None of the PVF changes were bilateral or concentric.