Use of the ratio of posterior to anterior corneal radii of curvature to improve the accuracy of intraocular lens power calculation
Session Details
Session Title: Presented Poster Session: Cataract Surgery Outcomes
Venue: Poster Village: Pod 1
First Author: : Y.Eom SOUTH KOREA
Co Author(s): : H. Lee Y. Suh J. Song H. Kim
Abstract Details
Purpose:
To evaluate the accuracy of intraocular lens (IOL) power calculation using adjusted corneal power according to the ratio of posterior to anterior corneal radii of curvature.
Setting:
Korea University College of Medicine
Methods:
123 eyes from 123 patients who underwent uncomplicated phacoemulsification with implantation of a Tecnis ZCB00 IOL were included. Adjusted anterior corneal radius and predicted posterior corneal radius were calculated from conventional keratometry (K) using the ratio of posterior to anterior corneal radii of curvature and fictitious refractive index of the cornea for a Scheimpflug camera. Then, adjusted corneal power was calculated from obtained anterior and posterior corneal radii using a thick lens formula. The median absolute error (MedAE) based on the adjusted corneal power was compared with that based on the conventional K in the Haigis and SRK/T formulae.
Results:
The mean ratio of posterior to anterior corneal radii of curvature was 0.813, and the fictitious refractive index of the cornea for the Scheimpflug camera was 1.3277. The mean difference between the adjusted corneal power and conventional K was 0.00 D. The MedAE based on the adjusted corneal power (0.29 D in the Haigis formula and 0.27 D in the SRK/T formula) was significantly smaller than that based on the conventional K (0.33 D and 0.35 D, respectively; P = 0.010 and P < 0.001, respectively).
Conclusions:
IOL power calculation using adjusted corneal power according to the ratio of posterior to anterior corneal radii of curvature provided more accurate refractive outcomes than the calculation using conventional K.
Financial Disclosure:
NONE
