37.4.3 Progressive Outer Retinal Necrosis

Treatment regimens for PORN are based largely on small case series of AIDS patients. Due to PORN’s poor prognosis, a multidisciplinary approach with an infectious disease consultation is favored. In a small case series, prolonged combination antiviral therapy demonstrated success in arresting progression of PORN, maintaining remission, and preventing involvement of the other eye [24]. For patients not responding to systemic therapy, intravitreal injections of foscarnet and ganciclovir have demonstrated some benefit [25, 26]. Prophylactic laser photocoagulation (described in the next section) is often used to decrease the risk of retinal detachment [25].

37.5 Role of Vitreoretinal Surgery in Viral Retinitis

37.5.1 Argon Laser Photocoagulation

Argon laser photocoagulation posterior to the edge of necrosis may be performed as prophylaxis against retinal detachment, which is the major cause of visual loss after acute manifestations have resolved. Recommendations include three or four rows of 500-μm spots placed posterior to the advancing border of retinitis. The chorioretinal scars produced by the laser burns act as “spot welds,” which may hold the retina in place in the event that retinal tears develop in the area of retinal necrosis, leading to subsequent retinal detachment in that area.

37.5.2 Retinal Detachment Repair

Retinal detachments (Fig. 37.2) in patients with CMV retinitis have been approached with scleral buckling, gas pneumatic retinopexy, and vitrectomy with either gas or silicone oil tamponade.

Fig. 37.2 Retinal atrophy and detachment following resolution of acute CMV retinitis