Calculation of IOL Optical Power Using OKULIX Ray-Tracing Software in Real Clinical Practice

Purpose. Comparative analysis of the accuracy of IOL optical power calculation using different biometric devices.

Patients and methods. The study included 30 patients (30 eyes) after monolateral implantation of different monofocal and multifocal IOL models with a mean follow-up of 3.0 ± 0.2 (3–4) months. The mean age was 63.5 ± 6.5 (48–84) years. In all cases, IOL implantation was preceded by cataract phacoemulsification or refractive lensectomy. For all patients, IOL optic power, axial length and keratometry data were obtained using IOLMaster 500, Pentacam HR, and Pentacam AXL+OKULIX devices. Clareon, IQ Vivity, Hoya 250/251, and XY1-SP Vivinex IOLs were implanted.

Results. The mean optical power for all implanted IOLs was +21.38 ± 3.50 D, range of values was +10.0 to +29.0 D. The average values of axial eye length were 23.50 ± 0.90 mm (21.25 to 25.19 mm). The target refractive IOLs optic power calculated with the three biometric systems did not differ significantly and was -0.464 ± 0.120 D, -0.502 ± 0.140 D, and -0.400 ± 0.110 D for IOLMaster, Pentacam, and Pentacam+OKULIX, respectively (p > 0.05). The Pentacam HR and Pentacam AXL+OKULIX had slightly lower MAE values; however, no significant differences were found in calculating IOL optical power for the three devices used (p > 0.05). When comparing the devices under study, significant differences were found for the rate of refractive power within ±0.5 D when using the IOLMaster on the one hand and OKULIX on the other (p < 0.05). The refractive error rate of ±1.0 D using the biometric devices did not differ significantly (p > 0.05).

Conclusion. This paper presents the first Russian experience of using OKULIX ray-tracing software in clinical practice to increase the accuracy of optical power calculation of various IOL models. The advantage of Pentacam AXL+OKULIX over the IOLMaster 500 biometer in achieving a target refraction of ±0.5 D is shown.

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