The Clinical Efficacy of the Haigis Formula Using A-Scan Contact Ultrasound Biometry

Abstract

Purpose: To investigate the accuracy of the Haigis formula compared to other formulas using contact ultrasound biometry. Methods: This study was performed on 94 patients (114 eyes) who underwent cataract surgery in our hospital. Axial length (AXL) and anterior chamber depth (ACD) were measured using both A-scan and intraocular lens (IOL) Master. Patients were divided into three groups based on AXL; Group I (AXL < 22.5 mm), Group II (22.5 mm ≤ AXL < 25.5 mm), and Group III (AXL ≥ 25.5 mm). Before cataract surgery, predicted refraction was calculated using the Haigis, SRK/T, Hoffer Q, and Holladay 1 formulas using both A-scan and IOL Master measurements. Mean absolute error (MAE) were analyzed at one month after surgery using the various IOL formulas. Results: Using contact ultrasound biometry, in Group I, MAE of Haigis was 0.80 ± 0.67 D and was significantly lower than that using SRK/T. In Group II, the Haigis MAE was 0.72 ± 0.55 D and was significantly lower than the results of all other formulas. In Group III, the Haigis MAE was 0.76 ± 1.13 D and not significantly different from the results of other formulas. Comparing MAE of A-scan to IOL Master, the Haigis formula showed 0.16 D higher error that decreased when the AXL was close to the normal range. Conclusions: Using contact ultrasound biometry, the Haigis formula provided the best predictability of postoperative refractive outcome compared to other formulas in eyes with normal axial length. J Korean Ophthalmol Soc 2014;55(12):1793-1799