Clinical features of acute retinal necrosis at Hokkaido University Hospital

Objective: To study clinical features of acute retinal necrosis (ARN) at Hokkaido University Hospital.

Methods: Twenty-one eyes of 19 patients with ARN (10 male and 9 female patients) who were treated at Hokkaido University Hospital between 1992 and 2006 were retrospectively examined from clinical records.

Results: The average age of the patients was 53.4 years (range, 13 to 91 years). 17 cases were unilateral and 2 were bilateral. The pathogenic virus was herpes simplex virus-1 (HSV-1) in 2 patients, and varicella-zoster virus (VZV) in 17 patients. Clinical severity was assessed from spreading speed and area of the retinal exudation, and 5 eyes were judged as fulminant cases (4 VZV eyes, 1 HSV eye), 6 eyes as severe cases (6 VZV eyes), and 10 eyes as mild cases (9 VZV eyes, 1 HSV eye). The range of retinal exudation was 1 to 2 quadrants in 7 eyes, 3 to 4 quadrants in 3 eyes, and increased to all quadrants in 11 eyes. Retinal detachment (RD) was observed in 8 eyes (38%), and the final visual acuity was less than 0.1 in 9 eyes (43%).

Conclusions: The leading cause of ARN at Hokkaido University Hospital was VZV, and no HSV-2 ARN was seen. Compared with other areas in Japan, ARN at Hokkaido University Hospital seems to show less frequent RD, but the same prognosis for final visual acuity.