# Level of Agreement of Intraocular Lens Power Measurements Between a Swept-Source OCT Biometer and a Partial Coherence Interferometer

## TL;DR

This study compares two eye-measuring devices to see how well they agree on measurements needed for cataract surgery.

## Contribution

The study provides new evidence on the agreement between SS-OCT and PCI in IOL power calculations.

## Key findings

- Argos measured higher anterior chamber depth and steeper keratometry values than IOLMaster.
- Mean IOL power differences were mostly within clinically acceptable thresholds.
- IOLMaster showed slightly more hyperopic prediction errors for some formulas, but differences were not clinically significant.

## Abstract

Background/Objectives: Swept-Source Optical Coherence Tomography (SS-OCT) is a novel optical biometry technology with limited published data on its reliability compared to the gold standard, partial coherence interferometry (PCI). This study aims to assess the agreement between an SS-OCT biometer (Argos) and a PCI device (IOLMaster 500) in terms of biometry values, intraocular lens (IOL) power calculation and mean prediction error (ME). Methods: In this prospective comparative study, axial length (AL), anterior chamber depth (ACD), flat (K1), steep (K2) and mean (Km) keratometry values, astigmatism power, J0, and J45 vector components, white-to-white distance (WTW), and IOL power calculations for nine IOL models using four formulas were compared in cataract patients. Refractive outcomes were assessed in eyes implanted with SN60WF and Panoptix IOLs, with ME calculated for each module and formula for both IOLs postoperatively. Results: This study included 133 eyes (mean age: 66.0 ± 10.95 years). Argos measured significantly higher ACD and steeper keratometry values than IOLMaster, albeit without significant differences in AL, astigmatism power, WTW, J0, and J45. Mean IOL power differences were within the clinically acceptable threshold (0.50 D), except for SN6ATx with Hoffer Q and Haigis, and Clareon with Haigis. For Panoptix and SN60WF, IOLMaster demonstrated a more hyperopic ME than Argos with SRK/T, Holladay 1, and Hoffer Q; however, this was without clinically significant differences. Conclusions: Argos and IOLMaster 500 presented differences in ACD, keratometry values, and IOL power calculation. However, both devices showed non-clinically significant differences in IOL power calculation and ME in the majority of formulas.