Clinical characteristics of progressive nonarteritic anterior ischemic optic neuropathy

Abstract

Aim: To study whether patients with progressive nonarteritic anterior ischemic optic neuropathy (NAION) present earlier than patients with stable NAION and to describe their clinical characteristics and visual outcome.

Methods: This was a retrospective chart review. All patients with NAION seen during the acute stage from January 2012 to December 2018 were reviewed. Patients were included if they had documented disc edema and follow up of at least 3mo. Patients with progressive NAION were identified if they worsened in 2 out of 3 parameters: visual acuity ≥3 Snellen lines; Color vision ≥4 Ishihara plates; the visual field defect involved a new quadrant. The clinical characteristics, time from symptom onset to presentation, systemic risk factors and visual outcome were compared to patients with stable NAION.

Results: Totally 122 NAION cases met the inclusion criteria. Mean age was 58.1y (range 22-74), 70% were men. Twenty cases (16.4%) had progressive NAION. Patients with progressive NAION did not differ from stable NAION in their demographics, systemic risk factors or in their initial visual deficit. At last follow up, median visual acuity was 1.0 logMAR (IQR 0.64-1.55) in patients with progressive NAION, vs 0.18 (IQR 0.1-0.63) in stable NAION (P<0.001). Median color vision testing was 0 plates correct (IQR 0-2.5%) vs 92% plates correct (IQR 50%-100%) in the stable NAION group (P<0.001). Patients with progressive NAION differed in the time from symptom onset to presentation (median 2d vs 5d, P=0.011).

Conclusion: We find no identifiable risk factors associated with progressive NAION. Progressors arrive earlier for ophthalmological evaluation.

Keywords: disc edema; nonarteritic anterior ischemic optic neuropathy; optic neuropathy; visual field defect.

Figure 1. The time from symptom onset to presentation

Box plot of the time in days from onset to presentation. Data was available for 20/20 patients with progressive NAION and 90/102 patients with stable NAION. The median time to presentation was 2d (IQR 1-5.2) in the progressive NAION group and 5d (IQR 3.0-8.7) in the stable NAION group. P=0.011 (Mann-Whitney U test). A center line of the box indicates the median value of data. Lower and upper boundary lines of the box are the 25% and 75% quartile, and marginal lines represent 95%CI of the data.