Retrospective analysis of an intraoperative aberrometry database: a study investigating absolute prediction in eyes implanted with low cylinder power toric intraocular lenses

Abstract

Robert J Cionni,1 Michael Breen,2 Cody Hamilton,3 Ravaughn Williams41The Eye Institute of Utah, Salt Lake City, UT, USA; 2North America Clinical Development and Medical Affairs, Alcon Laboratories, Inc., Fort Worth, TX, USA; 3Biostatistics, Alcon Laboratories, Inc., Fort Worth, TX, USA; 4Global Clinical Development and Medical Affairs, Alcon Laboratories, Fort Worth, TX, USAPurpose: To evaluate the spherical equivalent outcomes of intraoperative aberrometry (IA) power calculations compared with the surgeons’ preoperative power calculations in eyes implanted with AcrySof® IQ T3 intraocular lenses (IOLs).Patients and methods: We assessed data collected by an IA system from multiple centers in the United States. Data was from patients who had undergone cataract extraction by phacoemulsification with the use of the Optiwave Refractive Analysis System and whose eyes had been implanted with model SN6AT3 (1.5 diopter [D] at IOL plane) aspheric lenses. The analysis was performed in 2 stages: hypothesis generation and confirmatory testing. Confirmatory endpoints were a comparison of absolute prediction errors for IA for the implanted IOL versus preoperative formula power calculations.Design: Retrospective analysis of preoperative, intraoperative, and postoperative data concerning eyes implanted with model SN6AT3 (1.5 D) aspheric lenses from the AnalyzOR™ database.Results: Mean absolute IA prediction error was significantly lower than preoperative prediction error (paired difference: −0.06 D; p<0.0001); this was mirrored by the median paired difference of −0.04 D (p<0.0001). For eyes where the power of the implanted IOL differed from the power of the preoperatively planned lens, mean and median paired differences in prediction errors were greater: −0.13 D (p<0.0001) and −0.15 D (p<0.0001), respectively. The percentage of eyes with prediction error ≤0.50 D was significantly higher with IA (83.4%, n=5388/6460) than with the preoperative formula (76.5%, n=4942/6460, p<0.0001). When the powers of the implanted IOL and the preoperatively planned lens were different, the percentage of eyes with prediction error ≤0.50 D was 83.3% (2155/2587) for IA and 68.8% (1781/2587, p<0.0001) for the preoperative formula.Conclusion: IA produces more accurate spherical equivalent outcomes for eyes implanted with a low toric IOL than the preoperative formulas.Keywords: astigmatism, intraocular lenses, low toric lenses, spherical equivalent outcomes  

Keywords

• Astigmatism
• Intraocular lenses
• Low toric lenses
• Spherical equivalent outcomes