Refraction Predictability for a Capsulotomy-Fixated Intraocular Lens in Femtosecond Laser-Assisted Cataract Surgery.

Purpose: To evaluate the predictability of postoperative refraction for a capsulotomy-fixated intraocular lens (IOL) after femtosecond laser-assisted cataract surgery (FLACS).

Methods: Patients with age-related cataracts and no other eye disease who were implanted with the FEMTIS FB-313 IOL (Teleon Surgical BV) during FLACS were included. Using an IOLMaster 700 (Carl Zeiss Meditec), subjective refractive and biometric data were collected preoperatively and at a minimum of 3 months postoperatively. The prediction error (PE), defined as the actual minus predicted refraction, as well as IOL constant optimization and formula performance, were assessed, and the effect of preoperative biometry on the PE was investigated.

Results: A total of 70 eyes from 48 patients were included. Hyperopic shifts resulted from applying the Haigis, Holladay 1, SRK/T, and Barrett Universal II formulas, whereas the Hoffer-QST, Pearl-DGS, Cooke K6, EVO, and Kane formulas yielded myopic shifts. The Barrett Universal II formula predicted refraction most accurately, with 48% of eyes within the limits of ±0.25 D. After constant optimization, the formulas displayed significantly lower PEs. Preoperative anterior chamber depth and lens thickness were significantly correlated with the PE. The corresponding positive parameter estimates before and after lens constant optimization were identical.

Conclusions: Implantation of the capsulotomy-fixated FEMTIS IOL during FLACS is associated with increased systematic refractive PE, which is directly influenced by preoperative anterior chamber depth and lens thickness. IOL constant optimization enhances prediction accuracy. Relevant inaccuracies also persist in modern formulas, indicating that advancements beyond constant optimization might be crucial to enhance the predictability and accuracy of these calculations in clinical practice. [J Refract Surg. 2025;41(6):e532-e541.].