Prospective analysis of macular and optic disc changes after non-arteritic anterior ischemic optic neuropathy

Purpose. To prospectively analyse macular and optic disc changes after the occurrence of non-arteritic anterior ischemic optic neuropathy (NAION) and study possible predictors of final visual outcome. Methods. Patients with NAION underwent a complete ophthalmic examination, including spectral-domain optical coherence tomography of the macula and optic nerve head. The examination was repeated 1, 3, 6, 9 and 12 months after onset. Final visual prognosis was evaluated by visual field (VF) and best-corrected visual acuity (BCVA) at the final visit. Data within the NAION group were analysed over the course of the disease and compared to a disease-free control group at each visit. Results. Twenty-two eyes with NAION and 43 eyes from a control group were included. The retinal nerve fiber layer (RNFL) was significantly thicker in NAION eyes than controls at presentation (P=0.00), and significantly decreased during the next 3 months after presentation (P=0.02). The ganglion cell + inner plexiform layer (GCIPL) was thinner in the NAION group throughout the course of the disease (all P < 0.05). Although the acute NAION eyes had significantly lower cup/disc ratios and higher neuroretinal and disc sizes (all P=0.00), there were no significant differences between groups from the third month onwards (all P> 0.05). The best predictors of BCVA and VF were GCIPL at 3 months of follow-up (r(2) =0.32; P=0.03) and RNFL at 6 months of follow-up (r(2) =0.41; P=0.01) respectively. Conclusions. RNFL and optic disc changes occur during the first 3 months after the onset of NAION, whereas GCIPL is affected soon after the onset of symptoms. GCIPL and RNFL are useful predictors of final visual outcome. (C) 2019 Elsevier Masson SAS. All rights reserved.