Comparison Of Three Methods For The Calculation Of Intraocular Lens Power In High Myopia With Cataract

Objective:To compare the accuracy of three methods(LSW1,Barrett Universal?,Wang-Koch optimized axial length for Holladayl)for the calculation of intraocular lens power(IOL)in high myopia with cataract during different axial lengths.Methods:A retrospective case series comparison.Clinical data of 48 eyes in high myopia with cataract,who underwent phacoemulsification with IOL implantation in ophthalmology department of the Second Affiliated Hospital of Kunming Medical University from June 2018 to December 2018,were collected.Eyes were separated into 2 groups based on axial length(AL)as follows:long AL group(?26.0 mm to<30.0 mm)(24 eyes),extremely long AL group(?30.0 mm)(24 eyes).Preoperatively,appropriate target refrative error was selected for each patient,and appropriate IOL power of BigBag was implanted by referring to LSW1 formula.According to the results of postoperative refraction 3 mo after surgery,which were obtained by the subjective optometry,calculated the ideal IOL diopter(IOL idea)that could achieve emmetropia.Then using LSW1,Barrett Universal ?,Wang-Koch optimized AL for Holladayl formula to calculate the emmetropia IOL power(calculative IOL)respectively before surgery.The difference between the ideal IOL and the calculative IOL from three methods were the calculative error(CE-IOL),whose absolute value were the absolute calculative error(ACE-IOL).Results:(1)In the long AL group,both the LSW1 and the Wang-Koch optimized AL for Holladayl formula show myopic refractive error,which respectively were(-1.22±0.76)D,(-0.08±0.76)D.Barrett Universal ? presented hyperopia refractive error(0.23±0.80)D.In the extremely long AL group,LSW1 formula presented myopia refractive error(-0.24±1.11)D,Barrett Universal ? and Wang-Koch optimized AL for Holladayl formula both presented hyperopia refractive error,which respectively were(1.03±0.86)D,(1.01 ± 1.02)D.(2)In the long AL group,the ACE-IOL of LSW1,Barrett Universal ?,Wang-Koch optimized AL for Holladayl were(1.23±0.76)D,(0.65±0.50)D and(0.63±0.42)D,respectively.In the extremely long AL group,the ACE-IOL of three methods were(0.97±0.58)D,(1.11±0.76)D and(1.11±0.90)D,respectively.There were no statistically significant difference in the ACE-IOL of the LSW1 formula between two groups(P>0.05).The differences of ACE-IOLbetween two groups had statistically significant(P<0.05)in Barrett Universal ? and Wang-Koch optimized AL for Holladay1 formula.(3)In the long AL group,there were no statistically significant difference(P<0.05)about the ACE-IOL between the LSW1 and Barrett Universal ?,Wang-Koch optimized axial length for Holladayl formula.After pairwise comparison,results showed that LSW1 vs Barrett Universal ?,and LSW1 formula vs Wang-Koch optimized AL for Holladayl formula,the differences had statistically significant(P<0.05).Barrett Universal ? vs wang-koch optimized Holladayl formula,the difference had not statistically significant(P>0.05).There were not statistically significant(P>0.05)about the ACE-IOL bettween the three methods.(4)In the long AL group,the percentage of ACE-IOL between LSW1,Barrett Universal ? and Wang-Koch optimized axial length for Holladayl respectively were 37.50%,70.83%,83.33%for?1.0D and 62.50%,29.16%,16.67%for>1.0D,which had statistically significant differences between the three methods(P<0.05).In the extremely long AL group,the percentage of ACE-IOL between the three methods respectively were 54.17%,50.00%,50.00%for?1.0D and 45.83%,50.00%,and 50.00%for>1.0D,which had no statistically significant difference between the three methods(P>0.05).Conclusions:(1)The Barrett Universal ?,Wang-Koch optimized AL for Holladayl were equally accurate in calculativing the IOL power for the long AL eyes(26.0mm?AL<30.0mm)with cataract,but the last is better.(2)The LSW1,Barrett Universal ?,Wang-Koch optimized axial length for Holladay1 were equally accurate in calculativing the IOL power for the extremely long AL eyes(AL>30.00mm)with cataract,but the first is better.(3)The accuracy of IOL power calculated by Barrett Universal ?,Wang-Koch optimized axial length for Holladayl formula decreases with the extension of AL.