Automated evaluation of peripapillary choroidal thickness in nonarteritic anterior ischemic optic neuropathy

Purpose To compare peripapillary choroidal thickness (PTC) between eyes with nonarteritic anterior ischemic optic neuropathy (NAION), contralateral uninvolved eyes and masked healthy eyes by age using the automated choroidal segmentation provided by Swept Source Optical Coherence Tomography (SS-OCT Triton, Topcon, Japan). Methods 23 eyes with NAION, 15 uninvolved fellow eyes, and 28 healthy eyes were included in this cross-sectional observational study. .Automated choroid segmentation by SS-OCT was performed for a minimum of 6 months after the acute event. The Bruch's Membrane Opening based optic nerve area and peripapillary RNFL thicknesses were evaluated using SD-OCT Spectralis (Heidelberg Engineering GmbH, Heidelberg, Germany). The association between PCT and other potential confounding variables including age, gender, axial length, intraocular pressure and disc area was examined using univariable and multivariable regression analyses. Results The mean PCT in the NAION eyes, unaffected fellow eyes, and control group were 121.91 ± 69.7 μm, 133 ± 53 μm, and 116.2 ± 47.1 μm, respectively (ANOVA, p = 0.52). All peripapillary RNFL thicknesses (average and regional) were significantly thinner in NAION eyes compared with unaffected and healthy eyes (p = 0.000). Older age was significantly associated with a thinner mean PCT (rho −0.555, p = 0.000). Conclusions Although controversial regarding PCT in NAION exists in the literature using manual measurements, in the current study automated analysis did not find any significant differences in NAION eyes compared to both unaffected fellow eyes and control eyes.