Quantitative Analysis Of Peripapillary And Macular Vessel Densities In Primary Hypertensive Patients

?Purpose?: To observe the changes of macular capillary,radial peripapillary capillaries and retinal nerve fiber layer between normal people and primary hypertensive patients by using optical coherence tomography angiography(OCTA).?Methods?: This is a cross-sectional case-control study.We studied 61 eyes of hypertensive patients and 58 eyes of normal people.All subjects underwent OCTA examination with mode of retinal blood flow imaging in macular 6 mm×6 mm and optic disc 4.5 mm×4.5 mm area,signal strength >60,tonometry,axial length,fundus photography,blood pressure were included in the meanwhile.Patients with hypertension were grouped using international grading standards.Segment-spectrum amplitude decorrelation angiography(SSADA)was used to quantify the macular and radial peripapillary capillaries and the thickness of RNFL.The macular area was divided into 3 areas,which are parafovea,perifovea and fovea.The parafovea and perifovea are further divided into 4 areas respectively.The paramedial capillaries are divided into 8 parts unevenly.The superficial and deep vascular density in the macular region,the paramedial capillaries,RNFL thickness in the macular area(based on the ILM-IPL and in the ILM to RPE.)and foveal avascular zone area and perimeter were observed and analyzed by using the built-in analysis software in OCTA.?Results?The density of superficial vascular density in the macular area except the fovea was different in normal subjects,P = 0.000.There was no significant difference in the density of deep microvessels,P = 0.307.The thickness of ILM-IPL was different between the 8 regions,P = 0.000,And there is a positive correlation with the density of superficial vascular density,P=0.000,r=0.655.There was a negative correlation between deep blood flow density and ILM-IPL thickness.The correlation coefficient was-0.275,P=0.000.There was a positive correlationbetween RNFL and superficial blood flow density.The correlation coefficient was 0.194,P=0.000.The RNFL and paramedial capillaries are not related to age,P>0.05.Nasal RNFL thickness is significantly affected by systolic blood pressure.The blood flow density and RNFL thickness reduced while the systolic blood pressure decreased.?Conclusions?Short-term high blood pressure can affect blood flow density,and long-term fluctuations in blood pressure may lead to changes in retinal thickness and function.Hypertension,diabetes,age,hypoxia and other systemic factors can affect the fundus blood flow density.,We should pay attention to the effects of systemic factors on fundus vascular density and retina in clinical when using OCTA for early disease screening and diagnosis.