ESCRS - POCAT235 - Correction Of Aphakia Using Biometry-Based Contact Lens Calculation In Pediatric Cataract Extraction: Introducing The Aphakic Contact Lens Formula

Correction Of Aphakia Using Biometry-Based Contact Lens Calculation In Pediatric Cataract Extraction: Introducing The Aphakic Contact Lens Formula

Published 2026 - 44th Congress of the ESCRS

Reference: POCAT235 | Type: Free paper | DOI: 10.82333/wnfq-dw05

Authors: Dr Christoph Lwowski* 1 , Prof. Dr Thomas Kohnen 2 , Dr Yaroslava Wenner 2 , Dr Klemens Kaiser 2 , Dr Navid Farassat 3 , Prof. Dr Wolf Lagrèze 3

1Ophthalmology,University Clinic Frankfurt,Frankfurt am Main ,Germany;Ophthalmology,University Clinic Lübeck,Lübeck ,Germany, 2Ophthalmology,University Clinic Frankfurt,Frankfurt am Main ,Germany, 3Ophthalmology,University Clinic Freiburg,Freiburg,Germany

Purpose

To develop and test a formula for contact lens calculation in aphakic infants. This formula, termed the “aphakic Contact Lens” (aCL) formula, utilizes preoperative axial length and keratometry data.

 

Setting

 This retrospective, consecutive, two-center study (Freiburg and Frankfurt, University Clinic)

Methods

Data derived from a development cohort (Freiburg, Germany) was used to create and optimize the aCL formula in aphakic eyes. A separate validation cohort (Frankfurt, Germany) was used to validate its predictive performance. The accuracy of the aCL formula was compared against:  retinoscopy, a previously reported formula (Trivedi and Wilson, TW), and the use of a +32.0 diopter (D) CL. Performance was evaluated using the prediction error (PE), absolute prediction error (AE) and the number of eyes within a certain range from retinoscopy (±0.5D, ±1.0D, ±2.0D).

Results

The aCL formula demonstrated comparable absolute prediction errors to retinoscopy (median AE 0.53D vs. 0.69D) and outperforms the TW formula or +32D CL (median AE 3.25D and 2.63D). The number of eyes within ±0.5D (38.3%) is lower compared to retinoscopy (50.0%), but comparable for ±1.0D and better for ±2.0D (61.7% vs 66.7%, 83.3% vs 72.2%). Both perform better than TW formula and +32.0D (ranging from 0.0% for ±0.5D to 33.3% for ±2.0D).

Conclusions

 The aCL formula is a reliable and accurate tool for determining CL power in aphakic infants. It performed superior to other formula-based and default strategies and is comparable to a retinoscopy.