Comparison of predictions made by the intraocular lens master and ultrasound biometry

Objective: To ascertain whether a new instrument that uses partial coherence interferometry technology (Intraocular Lens Master [IOLm]) or ultrasound biometry provides a more accurate prediction of refractive outcomes in cataract surgery. Methods: This was a retrospective medical record review of 421 eyes of 304 patients who underwent cataract surgery with the IOLm and ultrasound biometry from January 3, 2002, to December 2, 2005. The mean difference between the prediction with each technology and the final spherical equivalent was compared. Circumstances in which both technologies failed to make accurate predictions were investigated. Results: The mean (SD) of the difference between predicted refraction and final spherical equivalent was -0.43 (0.84) diopters (D) for the IOLm and -0.60 (0.87) D for ultrasound biometry, indicating that on average the IOLm was a closer predictor than ultrasound biometry of the final spherical equivalent (P< .001). The IOLm had a 5% higher likelihood of predicting a spherical equivalent within 0.25 D than ultrasound biometry (P = .06), an 8% higher likelihood of predicting a spherical equivalent within 0.50 D (P<.001), and an 8% higher likelihood of predicting a spherical equivalent within 1.00 D (P<.001). Conclusions: To our knowledge, this is the most eyes examined for cataract surgery in a prospective fashion with both the IOLm and ultrasound biometry. The IOLm is a better predictor of postoperative refraction than ultrasound biometry, particularly within close ranges.