RT Journal Article A1 Ioshimoto, Gabriela A1 Takahashi, Beatriz Sayuri A1 Pessoa, Cristiano A1 Liber, Andre A1 Nagy, Balázs A1 Ventura, Dora A1 Damico, Francisco Max T1 Intravitreal injection of acyclovir causes dose-related retinal toxicity in rabbits JF Investigative Ophthalmology & Visual Science JO Invest. Ophthalmol. Vis. Sci. YR 2013 VO 54 IS 15 SP 5090 OP 5090 SN 1552-5783 AB Acute retinal necrosis is a rapidly progressive and devastating viral retinitis caused by the herpes virus family. Although systemic acyclovir is the treatment of choice, intravitreal injection of acyclovir may be used an adjuvant therapy during the first 2 days of treatment, while systemically administered acyclovir has not reached therapeutic levels in the retina. The aim of this study is to determine the functional effects of acyclovir in the rabbit retina after intravitreal injection. Acyclovir (0.1, 1, and 10 mg) was injected in the right eye of 30 New Zealand albino rabbits and sterile saline solution was injected in the left eye as control. Electroretinograms (ERGs) were recorded 1 day before and 2, 7, and 14 days after the intravitreal injection ERGs were recorded according to a modified ISCEV protocol. Data were analyzed comparing the four different pre- and post-treatment time points and treated and the non-treated eyes (Wilcoxon rank test). No statistically significant differences were found in the eyes injected with 0.1 mg. Eyes injected with 1 mg showed significant reduction in a- and b-wave amplitudes (day 2 and days 2 and 7, respectively) (p<0.05). Differences were not present in day 15. Eyes injected with 10 mg presented significant reduction in a- and b-wave from days 2 to 15 (p<0.05). No differences were found in implicit time. ERG results suggest that intravitreal injection of acyclovir in rabbits may cause dose-related toxicity to photoreceptors and post-receptoral cells. Functional changes caused by acyclovir 1 mg are reversible by day 15, but 10 mg causes irreversible changes. These findings suggest that intravitreal injection of acyclovir is a potential treatment for viral retinitis. RD 3/5/2021