Evaluation of eye back segment findings in optical coherance tomography-angio in patients with internal carotis stenosis

Purpose: To evaluate the effect of patients with mild to moderate internal carotid artery (ICA) stenosis on retinal blood flow, optic disc blood flow and choroid thickening with optic coherence tomography angiography (OCTA) and compare the obtained values with individuals without healthy stenosis. Material and Method: This is a prospective study, with a total of 75 participants included. According to IKA stenosis grade, healthy control group 1 (25 people), IKA stenosis 1-49% were group 2 (25 people), and IKA stenosis 50-69% were group 3 (25 people). The best corrected visual acuity (EIDGK), intraocular pressure (IOP), anterior segment, posterior segment examinations, and OCTA were taken to all participants, and macular superficial and deep capillary blood flow density, optic nerve head blood flow density, and choroidal thickness data were recorded. The results were examined and compared. Results: When compared and analyzed between groups there was a statistically significant difference between the three groups in mean superficial vascular density, deep vascular density, vascular density of Radial Peripaller Capillary (RPC) and choroid thickness (p <0.05). It was observed that group 3 was different from both groups for the whole (46,48 ± 3,54) and perifoveal area vascular density (47,18 ± 3,48) of the superficial capillary plexus (SCP), only group 3 and group 1 were different for the parafoveal area (48,53 ± 5,09) of SCP (p <0.05). It is seen that the deep capillary plexus (DCP) group 3 for the whole area vascular density (45,19 ± 5,67) is different with both groups, and group 3 and group 1 are different for DCP parafoveal (50,68 ± 4,26) and perifoveal area vascular density (46,74 ± 5,78) (p <0.05). It was observed that group 3 of RPC was different from both groups in the whole disc vascular density (47,61 ± 2,18) (p <0.05). In terms of subfoveal choroid thickness (212,25 ± 23,42), group 3 was found to be different from both groups (p <0.05). It was seen that group 3 was different from both group 1 and group 2 in choroidal nasal (145,05 ± 22,47) and choroidal temporal parameters (167,50 ± 23,11) (p <0.05). When the distribution of fovea-parafoveal-perifoveal parameters by groups was examined, no significant difference was observed in any variables. Conclusion: Compared to healthy controls, patients with moderate ICA stenosis revealed superficial / deep vascular density and decreased vascular density in the RPK layer and thinning in the choroid. Key words: Internal carotid artery stenosis, optic coherence tomography angiography, choroid, retinal vascular density.