Comparison Of The Accuracy Of The Intraocular Lens Calculation Formula For Predicting Refractive Error In High Myopia

Objective:Compare the accuracy of SRK / T,Haigis,HofferQ,Holladay1 and IOL optimization formulas to predict the accuracy of postoperative diopter in patients with high myopia,and study the correlation between the three types of implanted lenses and the formula It can provide a reference for the selection of suitable intraocular lens calculation formula and intraocular lens.Methods:Part I: Comparison of the accuracy of four types of intraocular lens calculation formulas and their axial optimization formulas for predicting refractive error in high myopia.Prospective clinical case study.A total of 18 patients(31 eyes)with cataracts with AL≥26.0mm were collected and divided into group A(26≤AL <30mm)and group B(AL≥30mm)according to the measured axial length.And the axial optimization formula is used to calculate the expected postoperative refractive power.Compare the actual measuredrefractive power with the expected postoperative refractive power.The accuracy of the four formulas at different axial lengths and the reliability of applying the axial optimization formula are analyzed.Part II: Correlation between different IOLs and IOL calculation formulas.Prospective clinical case study.According to the first part of the medical record data,according to the type of implanted intraocular lens,it is divided into group A(CT LUCIA 601 P type),group B(ZCB00 type)and group C(AR40e type).Four types of intraocular lens formula were used to calculate the expected postoperative refractive power.Compare the actual measured refractive power with the expected postoperative refractive power.Analysis of the effect of different intraocular lenses on predicting postoperative refractive power using the same intraocular lens formula.Results:There were 16 eyes in group A(26≤AL <30mm)with an average axial length of 27.70 mm,and 15 eyes in group B(AL≥30mm)with an average axial length of 31.76 mm.In group A,the four formulas of SRK / T,Haigis,HofferQ,and Holladay1 and their optimizing formulas for the axial axis are(1.61 ± 1.42)D,(1.67 ± 1.41)D,(1.85 ±1.54)D,(1.91 ± 1.52)D,(1.26 ± 1.25)D,(1.13 ± 1.28)D,(1.16 ± 1.31)D,and(1.24 ± 1.26)D.The four formulas and their eye axis optimization formulas have MNE values of(1.53 ± 1.51)D,respectively.,(1.48 ± 1.62)D,(1.76 ± 1.65)D,(1.83 ± 1.62)D,(1.05 ± 1.44)D,(0.79 ± 1.53)D,(0.91 ± 1.51)D,and(0.99 ± 1.47)D.There was no statistical difference in MAE and MNE between the formulas(P> 0.05).In Group B,the MAE values of the four formulas of SRK / T,Haigis,HofferQ,and Holaday1 and the optimizing formula of the axial axis are(1.82 ± 0.72)D,(1.54 ±0.72)D,(2.36 ± 0.69)D,(2.06 ± 0.69)D,(0.79 ± 0.76)D,(0.74 ± 0.82)D,(0.93 ± 0.85)D,and(0.71 ± 0.76)D.The MNE values of the four formulas and the eye axis optimization formula are(1.82 ± 0.72))D,(1.54 ± 0.72)D,(2.36 ± 0.69)D and(2.06 ± 0.69)D,(1.82 ± 0.72)D,(1.54 ± 0.72)D,(2.36 ± 0.69)D and(2.06 ± 0.69)D.Haigis and HofferQ formulas are statistically significant(F = 0.015,P = 0.004),HofferQ and SRK / T formulas are statistically significant(F = 0.217,P = 0.042),and there is no difference between Haigis and SRK / T formulas.Statistical significance(F = 0.102,P = 0.292).The MAE of the two formulas are smaller than the other two formulas.The MAE value of the Haigis formula is better,indicating better predictability.There is a statistical difference between MAE and MAE without optimization of the axis(P<0.05),indicating that the axis optimization formula can reduce errors and improve accuracy.Using SRK / T,Haigis,HofferQ,and Holladay1 formulas A and B,there was no statistical difference in the MAE between the two groups(P> 0.05).There were no MAE values between the four artificial lenscalculation formulas in the A and B groups Statistical difference(P>0.05).Conclusion: 1.There is no difference in the prediction accuracy of the four IOL formulas at 26≤AL <30mm.The Haigis and SRK / T formulas have better prediction accuracy for AL ≥ 30 mm,and the Haigis formula has more accurate prediction values.The application of the axe optimization formula can effectively reduce the error,so first optimize the length of the eye axis and select Haigis or SRK / T for AL≥ 30 mm The formula can get more accurate prediction results.2.Patients with high myopia and cataracts select the appropriate IOL formula according to the length of the eye axis.Implantation of CT LUCIA 601 P or ZCB00 IOL will not have a significant impact on the results.