Acute retinal necrosis

Aizman, A, Johnson, MW, and Elner, SG, 2007. Treatment of acute retinal necrosis syndrome with oral antiviral medications. Ophthalmology 114, 307-312. 

As mentioned above, intravitreal injection of drugs should be used in many cases to achieve therapeutic intravitreal drug levels. This is especially true for cases of viral retinitis, such as cytomegalovirus (CMV) retinitis and acute retinal necrosis (ARN) which require intravitreal injection of antivirals, or for the treatment of bacterial and fungal endophthalmitis or proliferative vitreoretinopathy [305]. It still remains a controversial issue whether liposomes can reach the retina after intravitreal injections and which vesicle physicochemical characteristics should be preferred for such formulations. 

Several randomized double-blind trials provided evidence that oral acyclovir 800 mg, five times daily, is the most effective dosage for treating HZO. Studies also stressed the importance of initiating treatment within the first 72 hours to prevent severe complications of HZO (i.e., keratitis, uveitis, secondary glaucoma, scleritis, optic neuritis, and acute retinal necrosis [ARN]).When there is ophthalmic involvement, it is recommended to treat even if the rash has been present for more than 72 hours. In addition, there is evidence that 7 days of treatment may be adequate. Studies have been shown that oral acyclovir may lessen the incidence and duration of postherpetic neuralgia associated with HZO, as shown in Table 11-10. 

Posterior uveitis Involves the choroid, overlying retina, and vitreous. The terms choroiditis, chorioretinitis, and retinochoroiditis are still used to describe specific conditions, for example, ocular histoplasmosis or acute retinal necrosis, but these conditions both technically constitute a posterior uveitis. 

Figure 31-2 Acute retinal necrosis syndrome, with confluent retinal whitening, vitreitis, and vasculitis. (Reprinted with permission from Holland GN, Tufail A, Jordan MC. Cytomegalovirus diseases. In Pepose JS, Holland GN, WUheknus KR, ed. Ocular infection and immunity. St. Louis, MO Mosby, 1996.)...

Duker JS, Blumenkranz MS. Diagnosis and management of the acute retinal necrosis (ARM) syndrome. Surv Ophthalmol... 

Fisher JR Lewis Ml, Blumenkranz M, et al.The acute retinal necrosis syndrome. Part 1 clinical manifestations. Ophthalmology 1982 89 1309. 

Ganatra JB, Chandler D, Santos C, et al. Viral causes of the acute retinal necrosis syndrome. Am J Ophthalmol 2000 129 166. 

Holland GN. Standard diagnostic criteria for the acute retinal necrosis syndrome. Executive Committee of the American Uveitis Society.AmJ Ophthalmol 1994 117 663. 

Matsuo T, Morimoto K, Matsuo N. Factors associated with poor visual outcome in acute retinal necrosis. Br J Ophthalmol 1991 75 450. 

A heavier-than-water fluorinated silicone oil was used in the treatment of 30 selected cases of complicated retinal detachment due to proliferative vitreoretinopathy (n = 19), proliferative diabetic retinopathy with traction detachment (n = 2), giant retinal tears (n = 5), ruptured globe with retinal detachment (n = 2), massive choroidal effusion with retinal detachment (n = 1), and acute retinal necrosis with retinal detachment (n = 1) (13). Initial retinal reattachment was achieved in all cases. Complications included redetachment (n = l), cataract (n = 6), raised intraocular pressure (n = 4), hypotony (n = 4), keratopathy (n = 3), uveitis sjme-chia formation (n = 3), phthisis (n = 2), choroidal hemorrhage (n — 1), and vitreous hemorrhage n = 1). 

A 40-year-old man developed acute retinal necrosis and was given intravenous aciclovir 15 mg/kg every 8 hours, in addition to intra-vitreal foscarnet 2.4 mg and topical moxifloxa-cin, prednisolone, and cyclopentolate [16 -The baseline serum creatinine was 53 pmol/l, which increased to 80 pmol/1 by day 2 (when oral prednisolone, 60 mg/day, was also started) and 265 p.mol/1 by day 3. Apart from the aciclovir, no other nephrotoxic agents were administered. Renal tract ultrasound was normal. Aciclovir was withheld after three doses and ganciclovir was started. His renal function normalized within 7 days. 

Minces LR, Gallagher DS, Shields RK. Acute retinal necrosis in a monocular patient complicated by acyclovir-induced nephrotoxicity. J Clin Virol 2010 49(1) 1-3. 

Viral endophthalmitis has become a major concern in AIE management, and some of uveitis are shown to arise from viral origin (e.g. acute retinal necrosis). Intravitreal antiviral therapy is surely one of the crucial modalities. The b-wave, the c-wave, the oscillatory potentials and the VEP remained unchanged after 5 repetitive weekly (once a week) intravitreal injections of 200 pig ganciclovir. 

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