Intravitreal Administration of Antiviral Agents in Silicone OileFilled Human Eyes
Amit Meshi, MD, Asaf Friehmann, MD, Sarah Sella, MD, Raz Gepstein, MD, Sharon Armarnik, MD, Ehud I. Assia, MD, Alexander Rubowitz, MD
Purpose: To report our experience with intra-silicone oil (SO) injection of antiviral agents for treatment of viral retinitis and to review the relevant literature. Design: Two case reports and a literature review. Participants: Two patients with viral retinitis and SO tamponade. Methods: Two patients with viral retinitis were treated with intravitreal injections of low-dose ganciclovir (2 mg/0.05 ml), foscarnet (1.2 mg/0.05 ml), or both after retinal detachment repair with SO tamponade, in addition to systemic antiviral therapy from 2014 through 2015. The literature on the use of intraocular antiviral agents in the setting of SO vitreous substitute was reviewed. Main Outcome Measures: Clinical outcomes after administration of intra-SO antiviral therapy. Results: A patient with progressive outer retinal necrosis received 5 intra-SO injections of low-dose ganciclovir and foscarnet after surgery over 6 weeks. Another patient with acute retinal necrosis received weekly low-dose foscarnet injections into his SO-filled eye for 8 weeks after surgery. Significant retinitis regression with long-term retinitis control was achieved in both patients throughout follow-up. No articles reporting the administration of soluble antiviral agents into an SO-filled human eye were identified. Conclusions: Our preliminary findings indicate that administration of low-dose ganciclovir and foscarnet into an SO-filled eye may be used as adjunctive treatment for viral retinitis. Further studies are needed to confirm these results. Ophthalmology Retina 2017;-:1e6 ª 2016 by the American Academy of Ophthalmology
Silicone oil (SO; polydimethylsiloxane) was introduced in administration.8 Intraocular therapy is an important method the early 1960s for treatment of retinal detachment (RD)1 of delivering antiviral medications. Reaching effective doses and since has become an invaluable aid to the retinal at the site of infection, avoiding systemic toxicity, achieving surgeon for managing complex surgical cases. Indications good local retinitis control, and delaying relapse are the for SO tamponade include, but are not limited to, complex main advantages of this method.8 Intravitreal ganciclovir, and traumatic RD, giant retinal tears, proliferative diabetic foscarnet, and cidofovir were shown to be safe and retinopathy, macular hole surgery, and endophthalmitis.2 effective adjunctive therapy for the management of Intravitreal administration of therapeutic agents for the patients with necrotizing herpetic and cytomegalovirus treatment of many vitreoretinal conditions, such as age- (CMV) retinitis.9e12 Rhegmatogenous RD is a common related macular degeneration, diabetic retinopathy, retinal complication of viral retinitis, especially in areas of thin and vascular diseases, uveitis, endophthalmitis, viral retinitis, atrophic retina,13 and many eyes require long-term SO and intraocular tumors, has become widespread in recent tamponade to maintain retinal reattachment.8 These patients years. Most injectable agents are water soluble and may still require intra-SO antiviral therapy because of reti- distribute evenly in the hydrophilic environment of the nitis. Ganciclovir was the only soluble antiviral agent vitreous humor. However, in the presence of SO tamponade, studied under SO in rabbit models, with inconclusive evi- the delivery and concentration of drugs injected into the dence regarding its safety.5,6 In immunocompromised pa- posterior segment of the eye become unpredictable.3 The tients, ganciclovir implant was shown to be safe and drug has to migrate through the oil and integrate gradually effective in controlling CMV retinitis with SO tamponade, into the vitreous fluid to reach the retina. This process and therefore has been advocated in such cases.14,15 We may affect its pharmacokinetic and pharmacodynamic report our experience with intravitreal antiviral administra- properties.4 A major concern in this situation is the tion in SO-filled eyes and review the current literature on the development of retinal toxicity resulting from high drug subject. concentrations in the thin film of fluid between the SO 5 and retina. Most information in the literature on the Methods administration of drugs into SO-filled eyes is derived from 4e7 rabbit models and has limited clinical application. Two patients with viral retinitis, one with progressive outer retinal Treatment of viral retinitis, a devastating ocular infection, necrosis (PORN) and another with acute retinal necrosis (ARN), often includes systemic and intraocular antiviral drug were treated at our ophthalmology department in 2014 and 2015.