Correction of axial length measurement error by IOLMaster 700 could improve refractive prediction accuracy in silicone oil‐filled eyes

Abstract Purpose To determine whether correcting the axial length (AL) measurement error of the IOLMaster 700 could improve the refractive prediction accuracy in silicone oil‐filled eyes. Methods This study included 265 cataract patients (265 eyes) with silicone oil tamponade who were scheduled for phacoemulsification with intraocular lens (IOL) implantation. The performances of various formulas, including Barrett Universal II, Emmetropia Verifying Optical, Hoffer‐QST, Kane, Ladas Super Formula, Pearl‐DGS, Radial Basis Function and traditional formulas (Haigis, Hoffer Q, Holladay 1 and SRK/T), were evaluated. The refractive prediction errors (PE) calculated with measured AL (AL meas ) and corrected AL with silicone oil adjustment (SO AL ) were compared. Subgroup analysis was performed based on the AL meas (<23 mm; 23–26 mm; ≥26 mm). Results Using SO AL significantly reduced the hyperopic PE of formulas when compared to AL meas (−0.05 to 0.17 D vs 0.15 to 0.38 D, p < 0.001). After applying AL correction, all formulas showed a lower mean absolute PE (0.47–0.57 D vs 0.50–0.69 D). The percentage of eyes within ±1.0 D of PE increased from 84.91%–88.68% to 89.81%–91.32% for new formulas and from 78.11%–83.40% to 85.66%–88.68% for traditional formulas, with the use of SO AL . Subgroup analysis showed that the majority of formulas with SO AL in prediction accuracy for eyes with an AL ≥26 mm ( p < 0.05). Conclusions The refractive prediction accuracy in silicone oil‐filled eyes was improved by correcting the AL measurement error of the IOLMaster 700, especially for long eyes.