Intraocular Lens Power Calculation in Myopic Eyes Undergoing Bilensectomy: Analysis of Comparability and Accuracy

Purpose: To address the calculation of intraocular lens (IOL) power in myopic eyes undergoing simultaneous anterior or posterior chamber phakic IOL (pIOL) explantation and lens extraction surgery, a procedure known as bilensectomy, in comparison to myopic eyes without pIOL (controls). Design: Retrospective analysis of comparability and accuracy. Setting: Department of Ophthalmology, Goethe-University, Frankfurt, Germany. Methods: IOLMaster 700 (Zeiss Meditec AG) and Pentacam AXL (Oculus Optikgeräte GmbH) were used for biometry. IOL power was calculated using the Barrett Universal II (BUII), Cooke K6, Hoffer-QST, EVO 2.0, PEARL-DGS, Hill-RBF, and Kane formulas included in the ESCRS online calculator, as well as the T2 and Ladas super formula and the SRK/T and Holladay 1 with or without Wang-Koch axial length adjustment. Results: Sixty eyes (mean axial length: 29.1±2.06 mm) of 60 patients (mean age 57.4±10.9 years) were included. Thirty eyes underwent bilensectomy and 30 served as controls. In bilensectomy eyes, Kane (0.53 D), PEARL-DGS (0.56 D), and Hill-RBF (0.61 D) demonstrated the lowest root-mean square of the absolute error. PEARL-DGS demonstrated the highest percentage of eyes within ±0.25D (46.7%), followed by BUII, Hill-RBF, and Kane (40.0%, each). EVO 2.0 showed a significant difference (p=0.001) in mean PE between the bilensectomy group and the control group. All other formulas showed no significant differences between the two groups (each p>0.05). Conclusion: Simultaneous explantation of a pIOL does not appear to exert a considerable impact on the IOL power calculation in myopic eyes. The performance of the formulas is comparable to myopic eyes without phakic IOLs.