Acute retinal necrosis: factors associated with anatomic and visual outcomes

Purpose To examine the factors associated with anatomic and visual outcomes in Japanese patients with acute retinal necrosis (ARN). Methods One hundred four patients with ARN who were followed for more than 1 year at nine referral centers were reviewed. Retinal involvement at initial presentation was classified into four groups: zone 1 (posterior pole, n = 22), zone 2 (midperiphery, n = 54), zone 3 (periphery, n = 25), and unknown ( n = 3). Forty-eight eyes underwent prophylactic vitrectomy before development of retinal detachment (vitrectomy group); 56 eyes were treated conventionally without prophylactic vitrectomy (observation group). Results The retina was attached in 28 of 48 eyes (58.3 %) in the vitrectomy group and 42 of 56 eyes (75.0 %) in the observation group at the final visit ( P = 0.071). At 1 year, 56 eyes (53.8 %) had a best-corrected visual acuity (BCVA) of 20/200 or worse. Multivariate logistic regression analyses identified zone 1 disease (odds ratio = 4.983) and optic nerve involvement (odds ratio = 5.084) as significantly associated with BCVA of 20/200 or worse. Among the zone 3 eyes, significantly ( P = 0.012) more eyes in the observation group than in the vitrectomy group had an attached retina. Conclusions Prophylactic vitrectomy did not improve the final BCVA in any eyes. Zone 3 eyes had better outcomes without prophylactic vitrectomy.