Analysis of intraocular lens displacement relative to the haptic plane by ultrasound biomicroscopy data

Abstract

This study analyzed cases with postoperative displacement of intraocular lens (IOL) relative to the haptic plane using ultrasound biomicroscopy (UBM). The study analyzed biometry data of 231 patients (277 eyes) aged 72.39±7.77 years, among them 43.25% were males. IOL position and refraction were analyzed at 1, 3 and 6 months after standard phacoemulsification. UBM was performed to analyze the position of the IOL. Stabilization of lens position was observed by the 3rd month of observation. Among the cases with displacement of the optical part relative to the haptic plane, the forward shift was determined in 24.85%, backward - in 16.67% of cases. Eyes with opposite IOL displacements differed significantly in lens diameter, ciliary sulcus diameter and the power of implanted IOL. IOL shift towards the retina produced significant hyperopic refractive error. A discriminant function was compiled using preoperative biometry data comprising the model for predicting backward IOL displacement with high probability. However, we failed to obtain a qualitative model for forward IOL displacements. Calculation error in modern formulas could occur because of IOL displacement, including the shift of the optical part relative to the haptic plane in postoperative period. Analysis of biometry data allows calculating IOL displacement towards the retina with a high probability, which could help avoid hyperopic refraction error postoperatively.