Posters

Optimizing IOL power calculation in cataract patients with naturally flat corneas

Poster Details

First Author: T.Jurecka CZECH REPUBLIC

Co Author(s):    O. Vlasak   V. Kalandrova                 

Abstract Details

Purpose:

To optimize IOL power calculation in cataract patients with naturally flat corneas (with no prior corneal surgery), specify ocular biometric parameters affecting IOL calculation accuracy for SRK/T, Hoffer Q and Haigis formulas. Improve final refractive results in this subgroup of patients.

Setting:

NeoVize Eye Clinic, Brno, Czech Republic

Methods:

Standard optical biometry with Zeiss IOL Master 400 and IOL power calculation using SRK/T, Hoffer Q a Haigis formulas were obtained in a group of 120 cataract patients with naturally flat cornea and central corneal power K< 41.5D. Subjective refraction was measured two months after uncomplicated cataract surgery and difference between target refraction and actual refraction for SRK/T, Hoffer Q and Haigis formulae were calculated. Accuracy of three formulae was tested.

Results:

Eyes with naturally flat cornea were associated with greater hyperopic shifts in postoperative refraction with the SRK/T formula, but not with the Haigis and Hoffer Q formulae. The Haigis and Hoffer Q generated slightly myopic results. The best accuracy of SRK/T formula was achieved in subgroup of eyes with flat cornea and preoperative anterior chamber depth ACD< 3mm (median= 2.98mm, SD= 0,26). There was less difference between target refraction and actual refraction two months after phacoemulsification for Haigis and Hoffer Q formulae (p<0.01).

Conclusions:

In cataract patients with naturally flat cornea (K< 41.5D) the Haigis and Hoffer Q would be the most accurate formulae. SRK/T formula generates hyperopic result in these patients with the exception of eyes with flat cornea and preoperative ACD< 3mm.

Financial Disclosure:

NONE