Theoretical and clinical comparison of the Haigis formula and 3rd generation formulas

Session Details

Session Title: Cataract Surgery Outcomes

Session Date/Time: Tuesday 16/09/2014 | 08:00-10:30

Paper Time: 10:08

Venue: Capital Hall A

First Author: : S.Kim SOUTH KOREA

Co Author(s): :    J. Jeong              

Abstract Details

Purpose:

To evaluate the biometric conditions causing increased disparity in the calculation of intraocular lens (IOL) power using Haigis and other 3rd generation formulas

Setting:

A retrospective review was conducted for 97 uneventful, cataract surgeries performed at a tertiary care center by one surgeon.

Methods:

IOL power was calculated using both the Haigis, Holliday, Hoffer Q and SRK/T formulas. For a selected IOL power, the expected disparity between the two formulas (EDF) was measured and the EDF value was used to categorize the cases. The resultant error associated with each formula was determined. KAL was defined as the product of mean corneal power (K) and axial length (AL).Effective lens position (ELP), EDF, and post-operative errors of both formulas, and their associations with preoperative biometry measurements.

Results:

In 17.8% of the cases, the EDF was larger than 0.4 D, possibly leading to different IOL diopter recommendations. The KAL showed high correlation with the differences of effective lens position (EPL) (R=0.700, p=0.000) and EDF (R=0.756, p=0.000). Statistically significant biometric factors causing EDF with Haigis formula was axial length for the Hoffer Q formula, and was corneal curvature for SRK/T formula, and was both of axial length and corneal curvature with Holliday formula.

Conclusions:

The cause of disparity between the predicted refraction for the two formulas was more highly associated with KAL than K or AL alone. Astigmatism, ACD, and LT acted as the causative factors for the post-operative errors in both formulas.

Financial Interest:

NONE