A-constants Optimization for Intraocular Lenses on the Clareon^® platform

Purpose. To optimize a-constants for intraocular lenses (IOL) on the Clareon® (Alcon, USA) platform. 

Material and methods. The study included 206 patients (206 eyes) divided into 4 groups depending on IOL implanted model: the 1^st — SY60WF (n = 71); the 2^nd — Clareon Toric CNW0T2-9 (n = 76); the 3^rd — Clareon PanOptix CNWTT0-Т6 (n = 32); the 4^th — Clareon Vivity CNWET0-Т6 (n = 27). Optical biometry was performed by IOL-Master 700 (Carl Zeiss, Germany). For toric IOL calculation keratotopography by CASIA Corneal/Anterior Segment OCT SS-1000 (Tomey, Japan) was performed. A month after phacoemulsification spherical equivalent of refraction was evaluated. Mean IOL calculation error (ME) was used to calculation accuracy assessment. A-constant optimization performed by ME zeroing. 

Results. ME was 0.32 ± 0.42 D for Clareon SY60WF, 0.31 ± 0.36 D for Clareon Toric CNW0T2-9, 0.38 ± 0.34 D for Clareon PanOptix CNWTT0-Т6 and 0.10 ± 0.34 D for Clareon Vivity CNWET0-Т6. ME zeroing allows to define real a-constants for IOLs: 119.38 for Clareon SY60WF, 119.46 for Clareon Toric CNW0T2-9, 119.54 for Clareon PanOptix CNWTT0-Т6 and 119.30 for Clareon Vivity CNWET0-Т6. 

Conclusion. Using of proposed a-constants for IOLs on Clareon® platform could help with target refraction achievement and to avoid a hyperopic refraction shift.

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