OCTA And Visual Field In Patients With Primary Glaucoma And Correlation Analysis Between Them

Objective:Optical coherence tomography angiography(OCTA)and Humphrey Field Analyzer were used to detect macular area and peripapillary vascular perfusion,structural changes,and visual field damage in patients with primary glaucoma,compare the differences in these parameters in different degree of primary glaucoma.By analyzing the correlation between vessel density,structure and visual field parameters,and comparing the diagnostic abilities of different OCTA parameters in patients with primary glaucoma,the application value of OCTA in patients with primary glaucoma was evaluated.Methods:A total of 45 patients(60 eyes)with primary glaucoma were selected as the experimental group and 17 normal subjects(30 eyes)as the contral group from July2020 to December 2020.All subjects received routine examinations such as best corrected visual acuity(BCVA),anterior segment and fundus under slit lamp examination,atrial angle examination,intraocular pressure,OCTA,and visual field examination.OCTA selects the following indicators:the Radial Peripapillary Capillary(RPC)segment is used to describe the peripapillary vessel density,superficial vascular density in macular area including whole image vessel density(wiVD),parafoveal vessel density(paraVD)and perifoveal vessel density(periVD),the analysis of macular ganglion cell complex(mGCC)and peripapillary retinal nerve fiber layer(pRNFL).Using Humphery Field Analyzer to measure pattern standard deviation(PSD)and mean deviation(MD).All patients with primary glaucoma in the experimental group were graded by Hodapp-Parrish-Anderson(H-P-A)and there were three groups:early stage(MD <-6d B),medium stage(-6d B≤MD≤-12 d B)and adcvanced stage(MD >-12).The obtained data were statistically processed and analyzed.Results:1.Comparison of vascular density in macular area and peripapillary vessel density:Compared to the normal group,the RPCVD,wiVD,paraVD and periVD of patients with primary glaucoma in early stage,medium stage and adcvanced stage were distinctively reduced,and the difference was significant(P<0.05).The RPCVD,wiVD,paraVD and periVD in early,middle and advanced patients were progressively reduced.2.Comparison of mGCC thickness and pRNFL thickness:Compared to the normal group,the mGCC thickness and pRNFL thickness of patients with primary glaucoma in early stage,medium stage and adcvanced stage were obviously lower,and the difference was significant(P<0.05).The thickness of mGCC and pRNFL in early,middle and advanced patients were progressively reduced.3.Relationship between vascular density,structural parameters and visual field damage:The peripapillary vascular perfusion,superficial vascular density in macular area,mGCC thickness and pRNFL thickness were all linearly positively correlated with the visual field MD(r > 0.5,P < 0.05).The correlation between the vascular density and the MD in the macular area was greater than that between the structural parameters(r=0.78 > 0.74),and the correlation between the vascular density and the MD around the optic disc was similar to that between the structural parameters(r=0.55 and 0.54,respectively).The correlation between the structural parameters in macular area and the MD was greater than that around the optic disc(r=0.74 > 0.54),the correlation between the vascular density in macular area and the MD was greater than that around the optic disc(r=0.78>0.55).4.The diagnostic abilities of each parameter for glaucoma:All parameters have good diagnostic abilities for glaucoma.It was found that diagnostic ability of vascular density and structural parameters is simila.Among them,wiVD and periVD in the macular area had the best diagnostic ability(their areas under the curve were 0.890 and 0.892,respectively).Conclusion:1.Compared with the normal control group,the vascular density and structural parameters in the macular area and peripapillary area of patients with early primary glaucoma were significantly decreased.With the progression of the disease,the vascular density and structural parameters were further decreased in patients with middle and advanced glaucoma.OCTA can be used in the early diagnosis and follow-up of patients with glaucoma.2.The correlation between VD and structural parameters and visual field defect was significant.The correlation between the vascular density and structural parameters in the macular area and the visual field MD value was better than that around the optic disc.The vascular density in the macular area can be used as a good indicator to evaluate glaucoma.3.The vascular density and structural parameters measured by OCTA both have good diagnostic ability in primary glaucoma patients,the diagnostic ability of vascular density and structural parameters is similar.Among vascular density,wiVD and periVD in the macular area has the highest diagnostic value,and OCTA may supply new parameters for the assessment of glaucoma in clinical application.