Correlation Between Retinal Vascular Density And Visual Field Loss In Primary Chronic Angle-closure Glaucoma

?Purpose?To evaluate the association between vessel density measurements using optical coherence tomography angiography(OCTA)and severity of visual field loss in primary open-angle glaucoma.?Design?Observational,cross-sectional study.?Participants?A total of 88 eyes from 52 healthy participants,118 chronic primary angle-closure glaucoma(CPACG)patients after glaucoma trabeculectomy enrolled in the Diagnostic Innovations in Glaucoma Study.118 CPACG patients,according to The Hodapp Classfication,were divided into 3 group including mild visual field loss group(MD>-6dB,32 cases of 42 eyes)and moderate visual field loss group(-12dB?MD?-6dB,27 patients with 31 eyes),severe visual field loss group(MD<-12 dB,30 patient with 39 eyes).? Methods ? All subjects underwent comprehensive ophthalmologic examination,including medical and family history,visual acuity examination,Humphrey visual field examination,computer optometry,axial and fundus photography,Structural OCT scans provided thickness measurements of the peripapillary retinal nerve fiber layer(RNFL)and macular ganglion cell complex(mGCC).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 >6.The superficial and deep vascular density(VD)in the macular region,circumpapillary were observed and analyzed by using the built-in analysis software in OCTA.?Main Outcome Measures? Associations between the severity of visual field loss,reported as mean deviation(MD),and OCT-A vessel density(VD).?Result?with CPACG eyes,normal eyes demonstrated a denser microvascular network within the macular.Vessel density was higher in normal eyes followed by mild CPACG,and moderate to severe CPACG eyes for total superficial VD in the macular area except the fovea(51.7%,48.45%,43.6%,and38.6%,respectively)(P < 0.00).There was no significant difference in the density of deep microvessels(P>0.05).circumpapillary VD(cpVD)was higher in normal eyes followed by mild CPACG,and moderate to severe(P < 0.01).The association between MD with cpVD of 4 regions and total superficial VD was stronger(R = 0.797,0.787,0.728,0.728 and R = 0.735,respectively)than the association between MD with RNFL of 4 regions(R = 0.673,0.653,0.529,0.568)(P < 0.05 for all).Multivariate regression analysis showed that each 1% decrease in total superficial VD was associated with 0.639 decibel(dB)loss in MD.Total superficial VD in the macular area,mGCC,cpVD,and RNFL have a certain effect on the diagnosis of CPACG.Each parameter is positively correlated with the degree of visual field loss.the MD decreases with each parameter respectively.Among them,total superficial VD in the macular area is highest.?Conclusion?Decreased VD was significantly associated with the severity of visual field damage.OCTA,a promising technology,provides a new method for the early diagnosis,quantitative assessment,and scientific follow-up of patients with CPACG.