Acute retinal necrosis (ARN) syndrome is a progressive peripheral necrotizing retinitis caused by herpes viruses.1, 2, 3, 4 As retinal detachment (RD) is its most devastating complication, prophylactic vitrectomy and retinal photocoagulation have been suggested.1, 2, 3, 4, 5, 6, 7, 8 This report presents the outcome of prophylactic vitrectomy in a case with severe ARN syndrome.

Case report

A 26-year-old man with 15-days history of right-sided visual loss was referred to our clinic. He had a visual acuity (VA) of 20/400, moderate anterior chamber reaction, dense vitritis, and 360° peripheral retinal necrosis in his right eye (Figure 1). Choroidal hypoperfusion of the necrotic areas was present in fluorescein angiography. Polymerase chain reaction of vitreous biopsy specimen revealed Herpes simplex virus type-1. His left eye was completely normal. Based on these findings, a diagnosis of ARN syndrome was made. Despite intensive medical treatment, necrosis and vitritis increased, and VA decreased to hand motions. Owing to this rapid deterioration, prophylactic pars plana vitrectomy, 360° endolaser photocoagulation involving the entire necrotic area and the adjacent healthy retina, and silicone oil tamponade was performed. Retinal lesions regressed, leaving atrophic changes, and VA increased to 20/30 within 3 months postoperatively (Figure 2a). However, after silicone–oil extraction in the fifth postoperative month, rapidly developing epiretinal membrane (ERM) and associated retinal tractional detachment, which involved the inferior retina, and extended towards the optic disc and the inferior temporal arcade, decreased the VA to counting fingers within 1 month (Figure 2b). Reoperation of ERM peeling, panretinal endolaser photocoagulation, and silicone–oil reinjection was performed successfully (Figure 3), and silicone–oil was extracted 6 months after this final operation. In his last examination 1 year after ERM peeling, retina remained attached, and his VA was stabilized at 20/60.

Figure 1
figure 1

Fundoscopy showing severe peripheral retinal necrosis at presentation.

Full size image
Figure 2
figure 2

(a) The appearance of the retina 3 months after vitreoretinal surgery. Note that the photocoagulation scars are visible, the retina is attached, and the necrosis has regressed. (b) The appearance of the retina after silicone–oil extraction. ERM formation and associated retinal traction is present.

Full size image
Figure 3
figure 3

The appearance of the retina 2 months after ERM peeling. Retina is reattached without any remaining complications.

Full size image

Comment

Complicated RD develops in 50–85% of cases with ARN syndrome.2, 5, 8, 9 In spite of aggressive surgical interventions, reattachment rate is low.6, 7, 9 Depending on this fact, prophylactic vitrectomy and retinal laser photocoagulation have been suggested in any eye with vitreous traction or opacification to reduce the rate of RD.2, 6, 7, 8, 9 However, the long-term visual prognosis of ARN syndrome is still poor as a result of its tendency to develop ERM after the operation.9 Most patients require more than one surgery.1 Likewise, postoperative ERM development and associated retinal traction occured in our case, which was thought to be the result of excessive amount of retinal pigment epithelium dispersion from the areas of retinal necrosis.

Although prophylactic vitrectomy may reduce the risk of RD in ARN syndrome, postoperative epiretinal proliferation and associated retinal traction remain as a major problem, which necessitate multiple operations in such cases.