Anatomical Lens Position Predictability for a Capsulotomy-Fixated Intraocular Lens in Femtosecond Laser-Assisted...

Area of Science:

• Ophthalmology
• Biomedical Engineering
• Optical Diagnostics

Background:

• Accurate prediction of anatomical lens position (ALP) is crucial for refractive outcomes after cataract surgery.
• Different intraocular lens (IOL) fixation methods, such as capsulotomy fixation versus intracapsular fixation, may influence postoperative lens positioning.
• Standard biometric parameters are used to predict IOL position, but their accuracy may vary with different IOL designs.

Purpose of the Study:

• To compare the predictability of anatomical lens position (ALP) between a capsulotomy-fixated IOL (FEMTIS) and an intracapsular IOL (TECNIS).
• To assess the influence of preoperative biometric parameters on ALP prediction for both IOL types.
• To evaluate the prediction error (PE) and absolute PE (AbsPE) for each IOL in relation to biometric data.

Main Methods:

• Analysis of pre- and 3-month postoperative data from optical biometry and swept-source anterior segment OCT.
• Definition of ALP as the distance between the corneal endothelium and the lens equator.
• Application of multivariate linear mixed-effects models to determine predictors of ALP, PE, and AbsPE.

Main Results:

• Both IOLs showed postoperative changes in anterior chamber depth (ACD) and lens position, with TECNIS exhibiting a larger ACD increase.
• Anterior chamber depth (ACD) and lens thickness (LT) were identified as the strongest predictors of ALP (R²=0.92 for FEMTIS, R²=0.97 for TECNIS).
• Lens thickness influenced PE in the FEMTIS group, while ACD influenced PE in the TECNIS group; AbsPE was less affected by parameters in the TECNIS group.

Conclusions:

• Anatomical lens position (ALP) is reliably predictable using standard biometric data, though with less accuracy for capsulotomy-fixated IOLs like FEMTIS.
• The capsulotomy fixation of the FEMTIS IOL may compromise refractive accuracy compared to intracapsular IOLs, necessitating adjustments in prediction formulas.
• Development of fixation-specific formulas and optimization strategies is crucial for enhancing the refractive predictability of capsulotomy-fixated IOLs.