Observing The Changes Of Macular Anatomy Before And After Surgery By OCT And Correlation Between Macular Anatomy And Vision Acuity In Idiopathic Macular Epiretinal Membrane

Objective:In this study,the characteristics of multi-slice and multi-regional scanning of frequency domain optical coherence tomography were used to observe the changes of macular anatomy before and after surgery in patients with idiopathic macular epiretinal membrane.The thickness and volume of the inner and outer retina in the macular area before and after surgery and its relationship with visual acuity were discussed.Methods:A retrospective study was performed on 25 patients(25eyes)with IMEM who underwent vitrectomy combined with stripping macular epiretinal membrane from December 2016 to January 2018.All patients underwent intraocular pressure,best corrected visual acuity,slit lamp microscope,fundus color photography and SD-OCT before and 6 months after surgery.Converts the best corrected visual acuity to 1ogarithm of the minimal angle of resolution(LogMAR).The thickness and volume of the whole,inner,middle and outer retina were recorded before and after surgery by SD-OCT,with self-contained Macular Thickness analysis softwares.All the results were input to perform a statistical analysis.Results:1.At 6 months after surgery,BCVA was significantly improved comparing with preoperation and the difference was significant(P <0.05).2.At 6 months after surgery,the changes of volume and thickness of retinal were basically consistent.In all ETDRS subregions,the thickness and volume in the whole and inner retina were reduced,reduction of retinal thickness in the central region of macular(1 region)and the temporal region of the inner ring(5 region)was particularly significant,and the difference were significant(P<0.05);In the middle retina,except for the nasal side of the inner ring(3 region),the thickness and volume of other areas were decreased before and after surgery,but the changes of only individual areas in the retinal thickness(9 region,the temporal side of the outer ring)and volume(6,8 and 9 region,the upper and lower part of the outer ring)were statistically different(P<0.05);in the outer retina,there was no significant difference in the thickness and volume of the retina in all regions before and after surgery(P>0.05).3.There was a positive correlation between BCVA and the thickness and volume in the whole,inner and middle retina before and after operation.There was no correlation between BCVA and the thickness and volume in the outer retina before operation.4.In the whole,inner and middle retina,the preoperative BCVA was positively correlated with the retinal thickness and volume in the central and inner ring areas before surgery,but not related to the outer ring area;postoperative BCVA and central and inner ring retinal thickness a volume are also positively correlated,regardless of the outer ring zone,except for7 region.Conclusions:1.Minimally invasive vitrectomy combined with anterior membrane stripping can effectively improve postoperative visual function in patients with IMEM;2.The increase of retinal thickness is one of the causes of visual loss in IMEM patients;3.In the central region of the macular,morphological changes in the inner retina of IMEM patients are more likely to cause damage to vision than changes in the middle retinal;4.In the whole,inner and middle retina,preoperative BCVA is related to the thickness of central and inner ring regions,regardless of the thickness of the outer ring region;and the postoperative BCVA is related to the thickness of the central and inner ring regions of the macular,not related to the outer ring region(except for 7 region).