Точность расчета трифокальной ИОЛ по данным эквивалентных кератометрических показателей в различных зонах

Abstract

Purpose. To identify the equivalent K-readings (EKR) data and keratometry zones for accurate calculation of trifocal IOL according to 7 formulas. Material and methods. The study involved 42 patients (42 eyes). All patients underwent surgical treatment of age-related cataracts or a refractive lensectomy with femtolaser accompaniment and implanted a trifocal IOL. All patients underwent optical biometrics (OA-2000 Tomey, Japan) and keratotomography (Pentacam-HR, Oculus, Germany). Preoperative calculation of IOL was carried out according to the data of the optical biometer OA-2000 (Tomey, Japan). After the period of refraction stabilization, IOL was retrospectively calculated using seven formulas (Haigis, Hoffer Q, Holladay 1, SRK/T, Barrett 2 Universal, Olsen and Holladay 2), biometric data OA-2000 and keratometric indicators Pentacam HR (EKR 65 %) in 10 corneal zones (from 0.5 to 5.0 mm in 0.5mm increments). For each formula/zone combination, the postoperative predicted refraction, mean absolute errors, and median absolute errors were calculated. Results. The lowest variance, mean absolute error and median absolute error of predicted postoperative refraction were obtained using the Haigis formula in the 3.5 mm zone. Conclusions. The most accurate calculation of trifocal IOL using EKR data is determined using the Haigis formula in the 3.5 mm zone. Keywords: keratometry, «Pentacam HR», keratotomography, equivalent K-readings, keratometry zone, IOL calculation.