不同锥体位置圆锥角膜的生物力学特征分析OA

Objective To analyze the biomechanical characteristics of keratoconus(KC)with different cone posi-tions based on tangential curvature.Methods This retrospective study included 100 KC eyes[divided into a central group(51 eyes,within 3 mm of the corneal center)and a paracentral group(49 eyes,outside 3 mm of the corneal center)based on the location of the maximum tangential curvature on the anterior surface]and 51 normal eyes(control group).Morpho-logical and biomechanical parameters of the eyes were obtained using Pentacam and Corvis ST.After adjusting for intraocu-lar pressure(IOP)and central corneal thickness(CCT),as well as biomechanically corrected intraocular pressure(bIOP)and thinnest corneal thickness(TCT),intergroup parameter comparisons were conducted.The diagnostic efficacy of the pa-rameters was analyzed using receiver operating characteristic(ROC)curves.Results The IOP,bIOP,CCT,and TCT pa-rameters were compared between the paracentral group and the normal group,as well as between the central group and the normal group,and the differences were statistically significant(all P＜0.05).Before adjustment,CBI,Integrated Radius,Max Inverse Radius,DA Ratio Max(1 mm),Peak Dist,dArc Length Max,cCBI,Radius,A1 Deflection Area,A1 Deflection Amp.,and HC dArc Length parameters were compared between the paracentral group and the central group,and the differ-ences were statistically significant(all P＜0.05).After adjusting CCT and IOP,TCT and bIOP,there were still 11 mechanical parameters with statistically significant differences between groups(all P＜0.05).The ROC curve analysis results showed that TBI,cCBI,CBI,Integrated Radius,and Max Inverse Radius had a higher ability to distinguish central KC from normal cornea(AUC=1.000,1.000,1.000,0.998,0.997),while their diagnostic efficiency decreased when distinguishing paracen-tral KC from normal cornea(AUC=1.000,0.968,0.968,0.936,0.948).Conclusion The position of the cone is a key variable affecting the biomechanical performance of KC.There is a significant biomechanical difference between central and paracentral KC,and this difference is independent of corneal thickness and IOP.When diagnosing early KC,clinicians should comprehensively judge biomechanical parameters based on the cone position to improve the accuracy of clinical screening and diagnosis.