Optical analysis to predict outcomes after implantation of a double intraocular lens magnification device

PURPOSE: To analyze the effect of different optical parameters of the eye on the outcomes of implantation of a double intraocular lens (IOL) magnification device in patients with low vision. SETTING: Fundación Oftalmológica del Mediterráneo, Valencia, Spain. METHODS: The eye's refraction and magnification before and after surgery were evaluated using a theoretical eye model based on paraxial optics approximation. Four parameters on which refraction and magnification are dependent were evaluated: anterior chamber depth (ACD), axial length (AL), mean keratometry (Km), and the distance between the 2 implanted IOLs. The 4 variables were analyzed separately in the first stage. Next, different combinations of ACD, AL, and Km values were studied. The goal was to predict what type of eye (in terms of ACD, AL, and Km values) is suitable for successful implantation of the double-IOL magnification device. RESULTS: Axial length had a significant influence on eye magnification. The Km value mainly affected refraction. The ACD did not influence the success of the procedure. The distance between the 2 IOLs was a decisive parameter in the analysis. CONCLUSIONS: Analysis of optical and biometric eye parameters could guide selection of patients for implantation of the double-IOL magnification device. Eyes with higher AL and Km values (myopic eyes) are the most suitable for this procedure.