Clinical Observation On Ocular Nerve And Blood Flow Change In Ischemic Cerebrovascular Disease

Objective: This study used corneal confocal microscopy(CCM)and optical coherence tomography angiography(OCTA)equipment to observe the corneal nerve and fundus vascular density in patients with ischemic cerebrovascular disease(ICVD).Methods: This study conducted CCM and OCTA examinations on 46 ICVD subjects,who were divided into ischemic stroke(IS)patients group and transient ischemic attack(TIA)patients group.During the same period,41 healthy individuals of similar age and gender were included as a healthy control(HC)group for analysis of corneal nerve and retinal blood flow.At the same time,this study will divide the IS patient group(a total of 18 subjects)who only experienced unilateral cerebral infarction into the affected eye group and the healthy eye group(this study will define the affected eye as the affected eye and the contralateral eye as the healthy eye)for a comparative analysis of retinal blood flow based on the location of the cerebral infarction.Results:(1)Corneal nerve fiber density(CNFD)in the ICVD group,n/mm ~2)、Corneal nerve branch density(CNBD),n/mm ~2)Corneal nerve fiber length(CNFL),mm/mm ~2)The values were 15.67 ± 6.46,24.91 ± 19.65,and 6.92 ± 2.80,respectively.Compared with the HC group of 21.60 ± 7.82,55.88 ± 27.46,and 14.95 ± 15.49,all three indicators showed a statistically significant decrease in nerve density(all results had P<0.05).(2)Blood flow density of the deep retina within 1 millimeter of the central macular area in the IS and TIA groups(unit: mm)~2)Significantly lower than the HC group,with statistically significant differences(P<0.01): 32.22 ± 11.73,30.43 ± 9.09,and 50.23 ± 10.05,respectively.At the same time,this value was significantly lower in the affected eye compared to the healthy eye in patients with only unilateral ischemic stroke,with a statistically significant difference(P<0.05): 28.35 ± 13.90 and 37.73 ± 10.12,respectively.And the area of the Foveal Avascular Zone(FAZ)between the three groups(in millimeters)~2)The difference was not statistically significant(IS group: 0.306 ± 0.121,0.309(0.214,0.371);TIA group: 0.328 ± 0.128,0.307(0.251,0.373);HC group: 0.329 ± 0.229,0.295(0.223,0.355),P<0.05).Conclusion: ICVD patients may experience a decrease in retinal microvascular density(VD)and a decrease in the number of subcutaneous nerve fibers in the cornea.There was also a significant decrease in retinal blood flow density in the affected eye compared to the healthy eye.TIA patients have already experienced changes in retinal blood flow before the appearance of neuroimaging manifestations,and TIA patients may have developed organic lesions in the eye before the onset of brain organic lesions.CCM and OCTA have shown great potential as non-invasive techniques for diagnosing ICVD.