Carotid Disease and Retinal Optical Coherence Tomography Angiography Parameters in Patients with Non-arteritic Anterior İschemic Optic Neuropathy

Purpose: To analyze the data and retinal microvasculature for nonarteritic anterior ischemic optic neuropathy (NAİON) patients referred to have carotid Doppler ultrasound from 2016 to 2020. Methods: In this case-control observational study, 30 NAİON patients evaulated with carotid doppler sonography. 22 NAION patients (at least 3 months after onset of symptoms) and 9 normal subjects underwent a complete ophthalmic examination including optical coherence tomography (OCT), optical coherence tomography angiography (OCT-A). NAİON eyes and fellow eyes were further divided into the groups according to presence of carotid stenosis (CS). NAION patients with CS were termed "CS-NAION"; those without were termed "NCS-NAION". Measurements of radial peripapillary capillary vessel density (RPC VD) and ganglion cell complex (GCC), disk retinal nerve fiber layer (RNFL) thickness were compared among groups. Results: Fourteen of 30 NAİON patients referred for carotid Doppler were positive for CS with all of such referrals having less than 50% stenosis. RNLF, GCC and RPC VDs were reduced in NAION eyes, when compared to controls and the fellow eyes. RPC VD was significantly lower in the temporal-superior (P=0.037) and the superior-temporal (P=0.012) sectors of the NCS-NAION patients than in the CS-NAION patients. No significant differences were found between CS-fellow eyes and NCS-fellow eyes in terms of RPC VDs, RNLF or GCC. Conclusion: Results of the study highlight the effect of carotid artery stenosis on ocular perfusion pressure in the pathogenesis of NAİON. More extensive studies are necessary.