Predictive Accuracy of Various Iol Power Calculation Formulae in High Axial Myopia: A Prospective Comparative Study

Abstract

PURPOSETo compare the accuracy of Intraocular Lens (IOL) power calculation formulae in high axial myopia. MATERIAL AND METHODS27 eyes of 22 patients with axial length between 26mm to 30mm were studied. The eyes were divided in to two groups, Group 1 with AL 26-28mm consisting of 23 eyes and Group 2 with AL 28-30mm consisting of four eyes. The predictive accuracy of four formulae SRK-T, Hoffer Q, Haigis and Holladay 2 were evaluated and compared. The statistical analysis was carried out with SPSS Software 21.0 version with P value >0.05 considered significant. RESULTSThe predictive capability within ±1 D of these formulae in Group 1 is 88% with SRK-T, 87% with Hoffer Q, 88% with Haigis and 91% with Holladay 2 and within ±0.5 D is 61%, 61%, 69% and 73% respectively. In Group 2 which consisted of 4 eyes with AL between 28-30mm the results were 83%, 83%, 84%, 90%, 59%, 61%, 70%, 71% respectively. CONCLUSIONThe performance of SRK-T, Hoffer Q and Haigis was comparable for target refraction of ±1.0 D, whereas Haigis and Holladay 2 gave relatively better results for target refraction of ±0.5 D for Group 1 and Haigis and Holladay 2 performed better for Group 2.