Clinical results in phacoemulsification using the SRK/T and Haigis formulas

Poster Details

First Author: F.Esteves PORTUGAL

Co Author(s):    F. Rodrigues   L. Duarte   J. Salgado Borges        

Abstract Details

Purpose:

Nowadays cataract surgery has also the purpose of refractive correction. Many factors may affect the final results such as the minimum astigmatism induced by surgery or the correct intra-ocular lens (IOL) calculation. After introduction of phacoemulsification with small incision techniques, minimizing cylindrical error, and continuous curvilinear capsulorhexis technique, the correct IOL power became a crucial step for good refractive outcome in the preoperative examination of cataract surgery. The purpose of this study was to evaluate the prediction of postoperative refraction using the SRK/T and HAIGIS formulas in phacoemulsification in eyes with medium axial length (22-26mm).

Setting:

Centro Hospitalar de Entre o Douro e Vouga - unidade de Sćo Sebastićo - Portugal

Methods:

Between March and November of 2010, patients needing cataract surgery accomplishing the study inclusion criteria were selected at our Ophthalmology Department. Exclusion criteria included other ocular and systemic pathologies that could interfere on the final visual acuity. On the day of surgery all patients underwent keratometry and IOL calculation using the SRK/T and HAIGIS formulas. The IOL dioptric power and final refractive results were recorded.

Results:

The study included 41 patients (41 eyes) where 19 right eyes and 22 left eyes. The mean initial astigmatism was -0.96D ± 1.20. The mean difference between the IOL implanted and the IOL calculated was +0.18D ± 0:44 for the SRK-T formula and +0.11D ± 0.50 for the Haigis formula. The mean final astigmatism was -1.14D ± 1.06, and the difference between the initial and the final was +0.18D ± 0.49. The mean final refractive error (spherical equivalent) was -0.59D ± 0:56 where 75.6% of the eyes had a BCVA of 20/20, 17% of 20/25, 4.9% of 20/30 and 2.4% (1 patient ) <20/400.

Conclusions:

There was an induced astigmatism by surgical entrance but with residual effect on the final refractive result. For the majority of the eyes, the IOL calculation formulas showed equally good predictability for the ideal IOL power. FINANCIAL DISCLOSURE?: No