Retinal toxicity induced by intravitreal ganciclovir injection: case series and systematic review

OBJECTIVE: This study aims to conduct a systematic review to summarize the rare retinal toxicity associated with intravitreal ganciclovir injections. METHODS: A retrospective analysis was performed on patients who received intravitreal ganciclovir injections at our institution (Jan 2021–Dec 2024). Following the PRISMA guidelines, databases such as PubMed, Cochrane Library, and Scopus were systematically searched to identify reported cases of retinal toxicity in the literature. RESULTS: A total of 16 cases (17 eyes) were included, comprising 5 cases (5 eyes) from our institution and 11 cases (12 eyes) from 11 published articles. The average age was 52 years (range, 26–79), with 13 patients (81.3%) being male. Thirteen cases were diagnosed with cytomegalovirus (CMV) retinitis, and 3 with acute retinal necrosis (ARN). Based on multimodal imaging, retinal toxicity was classified into three categories: crystalline retinopathy (6 eyes, 35.3%), toxic pigmentary retinopathy (7 eyes, 41.2%), and macular toxicity (8 eyes, 47.1%). Notably, crystalline retinopathy and toxic pigmentary retinopathy often coexisted with macular toxicity. All cases received ≥ 2 mg intravitreal ganciclovir, except one silicone oil-filled eye that received 1 mg. Approximately two-thirds of injections exceeded 4 mg per administration. CONCLUSION: This study provides an in-depth examination of the clinical features of retinal toxicity induced by intravitreal ganciclovir, systematically detailing its multimodal imaging characteristics and key points for early detection. The findings highlight that while intravitreal ganciclovir is effective in controlling primary disease progression, its potential for retinal toxicity requires careful consideration.