Objective To evaluate the ocular blood flow abnormalities in macula and optic papilla in patients with mild carotid stenosis by optical coherence tomography (OCTA), and analyze the correlation between blood flow indexes and degree of carotid stenosis.

Methods Forty patients with mild carotid stenosis were collected, including 27 patients with unilateral stenosis (27 eyes in the unilateral stenosis ipsilateral eye group and 27 eyes in the unilateral stenosis contralateral eye group and 13 patients with bilateral stenosis (26 eyes in the bilateral stenosis group). Ten cases with no-stenosis at the same age in the same period were set as the control group (20 eyes in the no-stenosis group). The OCTA was used to measure the macular vascular perfusion density, macular vascular length density, FAZ area, papillary vascular perfusion density, papillary vascular length density and other indicators.

Results There was no statistical significance in the FAZ area among four groups (P ＞ 0.05). The differences in vascular perfusion density and vascular length density of macula and papilla among four groups were statistically significant (P ＜ 0.05 ~ P ＜ 0.01). The vascular perfusion density of macula, vascular perfusion density and vascular length density of optic papilla in the bilateral stenosis group were lower than those in the unilateral stenosis ipsilateral eye group (P ＜ 0.05). The macular blood vessel length density in the bilateral stenosis group was lower than that in other three groups (P ＜ 0.05). The RI of common carotid artery and internal carotid artery were negatively correlated with the perfusion density of outer macular circle and overall vascular, and blood vessel length density of macular inner circle, outer circle and whole blood vessel (P ＜ 0.05 ~ P ＜ 0.01). The RI of common carotid artery and internal carotid artery were negatively correlated with the vascular perfusion density and vascular length density of the optic papilla (P ＜ 0.05).

Conclusions The blood perfusion of macular region in patients with bilateral carotid artery stenosis decrease significantly. The blood perfusion of macular region in patients with unilateral stenosis increases due to compensatory factors, but there is no significant change in macular region. The carotid RI is significantly related to the blood perfusion in macula and optic papilla. OCTA has a certain value in scientific research and clinical exploration of ischemic diseases caused by carotid artery stenosis.