Advancements in intraocular lens power calculation formulas

Area of Science:

• Ophthalmology
• Optical Engineering
• Artificial Intelligence in Medicine

Background:

• Intraocular lens (IOL) formula accuracy is crucial for refractive outcomes.
• Patient factors like axial length, age, and prior corneal surgery complicate IOL calculations.
• Advancements in biometry and AI are driving formula improvements.

Purpose of the Study:

• To review and compare recent intraocular lens (IOL) formulas.
• To identify the highest-performing formulas based on patient characteristics.
• To assess formula performance in challenging cases, including prior refractive surgery.

Main Methods:

• Review of recent studies comparing IOL calculation formulas.
• Analysis of formula performance based on axial length, age, and surgical history.
• Evaluation of theoretical, ray tracing, and AI-based formula approaches.

Main Results:

• Barrett Universal II formula demonstrates consistent high accuracy.
• Updated Olsen and Hill-RBF formulas show good prediction results.
• Kane formula, using AI, exhibits the best overall performance across all axial lengths.
• Barrett True-K formula is accurate for eyes with previous myopic refractive surgery.
• Challenging cases (short/long axial length, prior surgery) require special consideration.

Conclusions:

• Optical biometry and IOL formulas have advanced, improving refractive outcomes.
• Clinicians can optimize results using consistently accurate formulas.
• AI and advanced optics are enhancing IOL calculation precision.