| Objective:To observe the changes in the superficial retinal microcirculation and macular microstructure after vitrectomy in patients with center foveal involving rhegmatogenous retinal detachment（CIRRD）by optical coherence tomography and optical coherence tomography angiography,and to compare the differences in parameters of CIRRD eyes with different extent of macular detachment.Methods:Prospective clinical study.Forty-one patients with CIRRD who were admitted to the ophthalmology department of the First Affiliated Hospital of Hainan Medical College from March 2021 to July 2022 were enrolled in this study.The affected eyes were set as the CIRRD group and the fellow eyes were set as the control group.Secondly,the CIRRD group were divided into two groups based on whether the macular detachment went beyond 1250μm on the nasal side of the center foveal（the CIRRD-1 group within 1250μm and the CIRRD-2 group beyond 1250μm）.All CIRRD eyes were observed before vitrectomy and at 7,15,30,60 and 90 days after vitrectomy,and their vitreous cavity was tamponaded with silicone oil.The main parameters were logarithm of minimum angle of resolution visual acuity,perfusion density of the superficial retinal vascular complex（PSVC）,foveal avascular zone,macular ganglion cell layer thickness,and retinal nerve fiber layer thickness.Preoperative macular cystoid changes and outer retinal folds on the nasal,temporal,superior and inferior sides of the center fovea were recorded.The continuity of the external limiting membrane and ellipsoid zone under the center fovea（within 1000μm diameter）after surgery were observed.Comparison of main parameters was performed using statistical methods（CIRRD group versus control group;CIRRD-1group versus CIRRD-2 group）,and the correlations between the parameters were also analyzed.Results:In the early postoperative period,all CIRRD eyes had their retina reattached.At each postoperative time point,the values of macular ganglion cell layer thickness,inner circle and outer circle of optic nerve head PSVC and macula PSVC were less in the CIRRD group than in the control group,while the values of logarithm of minimum angle of resolution visual acuity,retinal nerve fiber layer thickness and foveal avascular zone area were larger in the CIRRD group than in the control group（all P<0.05）.Before and after surgery,logarithm of minimum angle of resolution visual acuity was less in the CIRRD-1 group than in the CIRRD-2 group,and visual acuity improved with time in both groups(Ftime=34.842,P<0.01;Fgroups=25.715,P<0.01).The postoperative intraocular pressure increased in both groups compared to the preoperative pressure,but the difference between the two groups was not statistically significant(Ftime=4.756,P<0.01;Fgroups=0.045,P=0.833).The macular ganglion cell layer thickness,optic nerve head PSVC and macula PSVC in the CIRRD-2 group were not identical to those of the CIRRD-1 group at the same time point,with some differences being statistically significant（all P<0.05）.About 93.8%of eyes with macular cystoid changes occurred within 2 areas in the CIRRD-1 group,and 87%of eyes with macular cystoid changes occurred more than 2 areas in the CIRRD-2 group（P<0.001）.All（100%）of the outer retinal folds in the CIRRD-1group occurred within 2 areas,while 85.7%of the CIRRD-2 group occurred in more than 2 areas（P<0.001）.The number of eyes with postoperative disrupted continuity of the external limiting membrane and ellipsoid zone under center fovea was less in the CIRRD-1 group than in the CIRRD-2 group（all P<0.05）.The logarithm of minimum angle of resolution visual acuity in the early postoperative period was positively correlated with disease duration,detachment went beyond 1250μm,outer retinal folds,foveal avascular zone and external limiting membrane and ellipsoid zone breaks（all P<0.05）,and negatively correlated with center circle of macula PSVC（all P<0.05）.The duration of CIRRD was positively correlated with foveal avascular zone area,inner circle of optic nerve head PSVC,external limiting membrane and ellipsoid zone breaks at 30 days postoperatively（r=0.323,P=0.039;r=0.333,P=0.034;r=0.551,P<0.001;r=0.399,P=0.010）,and negatively correlated with inner circle of macula PSVC at 30 days postoperatively（r=-0.395,P=0.011）.External limiting membrane breaks were positively correlated with ellipsoid zone breaks at 7,30 and 90 days postoperatively（r=0.426,P=0.006;r=0.469,P=0.002;r=0.575,P<0.001）.Conclusions:1.In the early postoperative period,CIRRD eyes with normal ocular pressure have impaired superficial retinal microcirculation in the macula and optic nerve head,thinning of the macular ganglion cell layer and thickening of the optic nerve fibre layer.2.The smaller the extent of macular detachment,the lesser the preoperative macular cystoid changes and outer retinal folds,the better the postoperative visual acuity improvement is expected.3.For CIRRD eyes with greater macular detachment,the ability to recover the postoperative superficial retinal microcirculation and macular microstructure was relatively poor.4.The duration of retinal detachment correlates with postoperative superficial retinal microcirculation and external limiting membrane break and ellipsoid zone break.The external limiting membrane break after surgery was positively correlated with ellipsoid zone break,and its integrity may promote ellipsoid zone recovery.5.The distance of 1250μm from the nasal side of the center fovea can be used as a marker to evaluate postoperative visual function in patients with CIRRD. |
