Optical Coherence Tomography Angiography in Nonarteritic Anterior Ischemic Optic Neuropathy

Abstract
Optical coherence tomography angiography (OCTA) has demonstrated good utility in qualitative analysis of retinal and choroidal vasculature and therefore may be relevant in the diagnostic and treatment efforts surrounding nonarteritic anterior ischemic optic neuropathy (NAION). Retrospective, cross-sectional study of 10 eyes of 9 patients with a previous or new diagnosis of NAION that received imaging with OCTA between November 2015 and February 2016. Two independent readers qualitatively analyzed the retinal peripapillary capillaries (RPC) and peripapillary choriocapillaris (PCC) for flow impairment. Findings were compared with automated visual field and structural optical coherence tomography (OCT) studies. Flow impairment seen on OCTA in the RPC corresponded to structural OCT deficits of the retinal nerve fiber layer (RNFL) and ganglion cell layer complex (GCC) in 80% and 100% of eyes, respectively, and to automated visual field deficits in 90% of eyes. Flow impairment seen on OCTA in the PCC corresponded to structural OCT deficits of the RNFL and GCC in 70% and 80% of eyes, respectively, and to visual field deficits in 60%–80% of eyes. OCTA can noninvasively visualize microvascular flow impairment in patients with NAION.