Acute retinal necrosis. Management and visual outcomes: a case series

BACKGROUND: The present study reports the functional and anatomical outcomes of eyes with acute retinal necrosis(ARN). METHODS: This is a retrospective case series conducted at a tertiary Eye Hospital from March 2015 to March 2020. Medical records of patients with clinical and laboratorial—Polymerase Chain Reaction (PCR)—diagnosis of ARN were reviewed. To identify factors related to the outcomes of visual acuity(VA) and retinal detachment (RD) over time, Cox proportional hazards regression modeling and survival analyses were used. RESULTS: Twenty-three eyes of 23 patients (16 male, 7 female) were reviewed. Based on the PCR results, 16 cases (69.6%) had Varicella zoster virus, 3 cases (13%) had Cytomegalovirus, 1 patient (4.3%) had Herpes simplex virus associated ARN, and 1 case (4.3%) had negative PCR. The incident rate for ≥ 2-line VA gain was 0.28/eye-year (EY) (95% CI 0.21 ± 0.26) while the rate of severe vision loss was 0.09/eye-year (95% CI 0.05 ± 0.08). The RD development was observed at a rate of 0.43/eye-year (0.42 ± 0.02), which occurred in 9 eyes with a mean time of 100 days after the initial presentation of ARN. Patients’ age was the only factor associated with 2-line or more gain in VA over time with a hazard ratio of 0.921 (95% CI 0.854–0.993, P = 0.032). CONCLUSIONS: Generally, although being crucial, treatment is not highly effective in improvement of VA and decrease of RD development, as well as vision loss, in patients with ARN. However, treatment prevents fellow eye involvement efficiently. Younger age is associated with better response to treatment and more chance to achieve better VA.