A Comparative Study Of Visual Acuity And Macular Microvascular Differences After Different Surgical Techniques For Idiopathic Macular Hole

Objectives:To compare pars plana vitrectomy（PPV）combined with conventional internal limiting membrane（ILM）peeling versus inverted flap technique（IFT）in idiopathic macular hole.To compare the macular microvasculature differences in cases.The efficacy of the two surgical methods were compared.In order to provide personalized plan for clinical diagnosis and treatment of IMH patients.Methods:This is a retrospective study.Patients with IMH who were initially diagnosed in the Ophthalmology Department of the First Affiliated Hospital of Kunming Medical University from May 2019 to August 2022 were collected.Patients with IMH who were clearly diagnosed as idiopathic macular hole based on their medical history,clinical manifestations,and auxiliary examinations（including fundus examination under slit lamp,optometry,fundus photography,and optical poherence tomography angiography）.A total of 24 patients with IMH were included according to the inclusion criteria.Group 1:12 of them（12 eyes）accepted PPV combined with internal limiting membrane peeling;Group 2:12 cases（12 eyes）accepted PPV combined with IFT.All patients had surgical indications and were followed up for 6months.The best corrected visual acuity（BCVA）was evaluated before surgery and at1 month,3 months and 6 months after surgery.Optical coherence tomography angiography（OCTA）parameters were recorded,including foveal avascular zone（FAZ）area,FAZ perimeter,vessel density（VD）in the superficial capillary plexus（SCP）and deep capillary plexus（DCP）,which including the parafovea and perifovea.To explore the possible differences in the recovery process of IMH treated by two surgical methods.Statistical methods:SPSS26.0 software was used for data analysis and processing,and all data were analyzed for normality.All data are expressed as the means±standard deviations,and count data were represented by use cases.The t-test or rank-sum test was used for between-group comparisons of measurement data,the paired-samples t-test or rank-sum test was used for within-group comparisons,and the chi-square test was used for categorical data.Differences were considered statistically significant when p<0.05.Results:In this study,3 males and 9 females were included in the first group of PPV combined with ILM peeling,with an average age of 64.58±3.92 years,an average course of disease duration of 5.42±3.65 months,and an average minimum hole diameter of 450.75±171.53μm.In the second group of PPV combined with IFT,6 males and 6 females were included,with an average age of 62.08±4.60 years,the mean course of disease was 6.75±3.79 months,and the mean minimum hole diameter was 463.50±207.70μm.1.The changes before and after the operation were compared with those in the PPV and ILM peeling group:there were statistically significant differences between BCVA3 and 6 months after the operation（p₃=0.001,p₆<0.001）.The FAZ area values after surgery at 1,3 and 6 months were statistically significant from those before treatment（p₁<0.001,p₃<0.001,p₆=0.018）.The FAZ perimeter values after surgery at 1,3 and6 months were statistically significant from those before treatment（p₁<0.001,p₃<0.001,p₆<0.001）.The whole DCP vessel density in macular area after surgery at 6months were statistically significant from those before treatment（p₆=0.031）.The SCP vessel density in parafovea area after surgery at 1 months were statistically significant from those before treatment（p₁=0.002）.The SCP vessel density in perifovea area after surgery at 1 and 3 months were statistically significant from those before treatment（p₁=0.002,p₃=0.008）.The DCP vessel density in parafovea area after surgery at 1 and3 months were statistically significant from those before treatment（p₁=0.001,p₃=0.003）.The DCP vessel density in perifovea area after surgery at 1 months were statistically significant from those before treatment（p₁=0.008）.The results of other indexes were not statistically significant（p>0.05）.2.The changes before and after the operation were compared with those in the PPV and IFT group:there were statistically significant differences between BCVA 3 and 6months after the operation（p₃=0.009,p₆<0.001）.The FAZ area values after surgery at1,3 and 6 months were statistically significant from those before treatment（p₁<0.001,p₃<0.001,p₆<0.001）.The FAZ perimeter values after surgery at 1,3 and 6months were statistically significant from those before treatment（p₁<0.001,p₃<0.001,p₆<0.001）.The SCP vessel density in parafovea area after surgery at 1 months were statistically significant from those before treatment（p₁=0.025）.The SCP vessel density in perifovea area after surgery at 1 and 3 months were statistically significant from those before treatment（p₁=0.001,p₃=0.003）.The DCP vessel density in parafovea area after surgery at 1 months were statistically significant from those before treatment（p₁=0.032）.The results of other indexes were not statistically significant（p>0.05）.3.Compare ILM group and IFT group:The whole DCP vessel density in macula area after surgery at 3 and 6 months were statistically significant from those before treatment（p₃=0.023,p₆=0.016）.The DCP vessel density in parafovea area after surgery at 1,3 and 6 months were statistically significant from those before treatment（p₁=0.040,p₃=0.026,p₆=0.001）.The DCP vessel density in perifovea area after surgery at 1 and 3 months were statistically significant from those before treatment（p₁=0.023,p₃=0.021）.The results of other indexes were not statistically significant（p>0.05）.Conclusions:No matter PPV combined with ILM peeling or PPV combined with IFT,the two surgical methods can effectively improve patients’visual acuity,promote the closure rate of macular holes.Compared with ILM peeling group,IFT group resulted in fewer changes in blood flow density,especially in DCP.