Comparison Of Keratometry Measurements Between Pentacam Axl And Iolmaster 700 In Patients Undergoing Toric Intraocular Lens Implantation: A Pilot Study

To evaluate and compare ocular keratometric measurements obtained from the Pentacam AXL and IOLMaster 700 in patients undergoing toric intraocular lens (IOL) implantation following cataract surgery or clear lens extraction.

Hospital Arruzafa, Córdoba (Spain)

In this pilot study, patients undergoing toric IOL implantation were evaluated using the IOLMaster 700 and Pentacam AXL. Recorded parameters included SimK1, SimK2, TK1, and TK2 for IOLMaster 700, and SimK1, SimK2, TNP K1, TNP K2, TCRP K1, and TCRP K2 for Pentacam AXL. Devices were used in random order, with measurements performed by blinded expert operators. The Asqelio Trifocal Toric lens and Barrett True-K TK were used. IOL centration was assessed via Pentacam AXL retroillumination, and postoperative refraction was recorded one month after surgery.

A total of 25 eyes were analyzed. Significant differences in mean keratometry (K mean) were found between anterior surface keratometry (SimK) and total keratometry (TK) using Pentacam AXL (42.97 ± 1.30 D vs. 42.24 ± 1.24 D, p < 0.001). No significant differences were observed with IOLMaster 700 (43.26 ± 1.31 D vs. 43.30 ± 1.29 D, p = 0.09). ANOVA showed significant differences (p = 0.01) between TK Pentacam and both TK and SimK from IOLMaster 700, with a 1.0 D discrepancy. Mean astigmatism was higher with IOLMaster 700 (1.52 ± 0.43 D) than Pentacam AXL (1.27 ± 0.37 D), but the difference was not significant (p = 0.22).

This study highlights significant discrepancies in keratometric measurements between the Pentacam AXL and IOLMaster 700, particularly in total keratometry values. The observed 1.0 D difference in keratometry between devices could have a direct impact on IOL power calculations, potentially affecting refractive outcomes. While differences in astigmatic power measurements were observed, they did not reach statistical significance. These findings emphasize the importance of understanding inter-device variability when selecting keratometry values for toric IOL planning.