Abstract
Purpose :
To determine if there is an advantage to higher dose or IV antiviral therapy in the time to improvement (TTI) of retinitis and rates of retinal detachment (RD) in patients with acute retinal necrosis (ARN).
Methods :
Patients with ARN seen at the Cole Eye Institute from 2012 to 2022 were retrospectively reviewed. Those with widefield fundus photography at presentation and an anterior chamber (AC) sample positive for HSV or VZV DNA were included. All eyes received at least 1 intravitreal injection of Foscarnet 2.4mg/0.1ml. Patients were grouped by their initial antiviral therapy dosage. Exam records and serial fundus photographs were reviewed to determine time duration from the initial treatment until improvement in retinitis or pigmentation of borders was observed (TTI), whether an RD occurred, and time from initial treatment to RD (TTRD).
Results :
Twenty-nine eyes of 24 patients were included. Nine eyes were initially treated with valacyclovir 1g three times daily (Group 1), 12 with valacyclovir 2g three times daily (Group 2), and 8 with weight-based IV acyclovir (Group 3). There was no difference in number of injections between groups (p=0.5). RD occurred in 5/9 (56%) of Group 1 eyes, 9/12 (75%) of Group 2 eyes and 6/8 (75%) of Group 3 eyes. Eyes were categorized by presenting clock hours of retinitis. Rates of retinal detachment were similar across treatment groups and depended on presenting retinitis burden and not antiviral therapy. In eyes that demonstrated improvement in retinitis before detachment, TTI was similar across groups (Group 1 = 30 days; Group 2 = 21.1 days; Group 3 = 17.8 days). However, there was a large difference in average TTRD between groups, with Group 1 averaging 20.2 days (range 4-33), Group 2 averaging 87.8 days (range 1-352) and Group 3 averaging 90.5 days (range 20-271). Additionally, 5/5 (100%) of Group 1 RD’s occurred before improvement in retinitis was documented, whereas this was only seen in 2/9 (22.2%) of Group 2 RD’s and 0/6 (0%) of Group 3 RD’s.
Conclusions :
ARN is a visually devasting condition associated with a high rate of RD (56-75%). While this series did not demonstrate an advantage to higher dose antivirals in preventing RDs or a shorter TTI in those demonstrating improvement before RD, it does show higher rates of retinitis improvement before RD and a more delayed RD timeframe in eyes receiving higher dose oral or IV antiviral therapy.
This abstract was presented at the 2023 ARVO Annual Meeting, held in New Orleans, LA, April 23-27, 2023.