Lens Thickness Distribution And Influence Factors In Cataract Patients:A Multi-Center Retrospective Study

Objective: This study aimed to analyze the distribution of lens thickness(LT)and its associations with age,gender,anterior chamber depth(ACD),and axial length(AL)in multicenter cataract patients data.Methods: This multicenter cross-sectional study included 59,726 Chinese age-related cataract patients.Repeated measures of ocular parameters were performed using an IOL Master 700 device.The distributions of ocular biometric data including anterior chamber depth(ACD),LT,axial length(AL),central corneal thickness(CCT),white to white(WTW)and mean keratometry(MK)and their associations with age were assessed,Anterior segment length(ASL)was measured as sum of CCT,ACD,and LT,while vitreous chamber depth(VCD)was calculated as the difference between AL and ASL.The values of LT:AL,ASL:AL and VCD:AL in different AL groups and their changes are the main outcome measure used to observe the proportion of the anterior and posterior segments of the eye.Results:1.Biometric data were available for 59,726 individuals.Mean age was 68.81 years(range=40-100);40.62% were male and 59.38% were female.2.Mean LT was 4.5±0.44 mm,The mean values of LT in each age group were 4.14±0.37(<50 years),4.29±0.41(50-59 years),4.48±0.42(60-69 years),4.60±0.41(70-79 years),4.70±0.41(≥80 years)mm.3.Female patients(4.50±0.43mm)had thinner lens than male patients(4.52±0.45mm).4.ACD revealed the strongest negative correlation(p < 0.001,r=-0.682)with LT,Age(p<0.001,r=0.348)showed a moderate positive correlation,whereas MK(p<0.05,r=0.011),CCT(p<0.001,r = 0.041)had a weak positive correlation and WTW(p<0.001,r =-0.034)had a weak negative correlation with LT.5.A non-linear correlation was found between LT and AL,LT changed variably in eyes with AL less than 27 mm,LT decreased as AL increased,then LT gradually increased as AL increased in extremely long and extra-long eyes.(p<0.001).6.LT:AL and ASL:AL decreased as AL increased,VCD:AL gradually increased as AL increased in highly myopic eyes,and VCD:AL increased about 0.01 for every 1 mm increase in AL.Conclusions:1.The mean LT of 59,726 cataract patients in China is4.51±0.44 mm,and 74.45% of the patients had LT within 4.00-5.00 mm.2.LT in females is thinner than that in males,Lens was thicker in elderly patients,there is a strong negative correlation between LT and ACD,MK and CCT had a weak positive correlation and WTW had a weak negative correlation with LT.3.The correlation between LT and AL is not a simple negative correlation,with the increasing of AL,LT decreases first and then increases.4.The proportion of VCD is constantly rising with elongation of AL.