Intra-operative aberrometry versus conventional biometry for intraocular lens power calculation: A prospective observational study from a tertiary referral center

Abstract

Purpose: To evaluate the per operative intra-ocular lens (IOL) power calculation using intra-operative aberrometry (ORA) and its comparison with conventional methods. Methods: Patients with cataract planned for phacoemulsification by a single surgeon under topical anesthesia were enrolled in this prospective observational study in this prospective observational study. All patients underwent pre-operative biometry (Manual SRK-II and IOLMaster® 500) to determine the intra-ocular lens (IOL) power. Intra-operative aberrometry using ORA was also performed; however, IOL was inserted according to IOLMaster® (SRK/T). Spherical equivalent (SE) was recorded on post-operative days 1, 7, and 30. Patients were divided into three groups based on axial lengths for analysis. Comparative analysis was performed for the calculated IOL powers and prediction errors of ORA with conventional methods. Adjusted IOL power to calculate the emmetropic IOL using the LiHue formula was also determined and was compared with existing methods. A P-value less than 0.05 was considered statistically significant. Results: A total of 115 eyes from 113 patients were included, with a median age of 54.90 ± 14.3 years. The mean axial length was found to be 23.94 ± 2.3 mm. There was good agreement (87%) between ORA and IOLMaster® for calculated IOL powers with a mean difference of 0.047 ± 0.5D between the two (P = 0.33). A positive correlation was found between IOL power calculated using ORA, IOLMaster®, SRK-II, and adjusted IOL. Conclusion: The use of intra-operative aberrometry (ORA) to calculate IOL power in patients undergoing uncomplicated phacoemulsification is non-inferior relative to standard pre-operative measurement and planning.

Keywords

• biometry
• intra-operative aberrometry
• iolmaster
• optiwave refractive analysis