Comparison of Biometric Measurements and Refractive Results among Low-coherence Reflectometry, Partial Interferometry and Applanation Ultrasonography

ABSTRACT

PURPOSE: To compare the measurement results and the accuracy of the predicted refractive error after cataract surgery among 3 ocular biometry devices; OA-2000®, IOL Master® and A-scan ultrasound in posterior subscapular cataracts. METHODS: Biometry measurements including axial length, anterior chamber depth and the keratometry of 80 cataractous eyes were measured using ultrasonography, OA-2000® and IOL Master®. To calculate the intraocular lens (IOL) power, the SRK/T formula was used and 3 months after cataract surgery, the refractive outcome was compared to the preoperatively predicted refractive error. RESULTS: The number of eyes measured by the 3 devices (A-scan, IOL Master® and OA-2000®) was 57 (group A) and the number of eyes measured by 2 devices (A-scan and OA-2000®) was 22 (group B). When cataract grading was performed based on the Lens Opacity Classification system III, the severity of posterior subscapular opacity was significantly different between the 2 groups (p = 0.001). Although no difference was observed in the measured biometry values including axial length, anterior chamber depth and keratometry in groups A and B, the predicted refractive error was significantly different in group B; OA-2000® showed a significantly higher accuracy in predicting IOL power than A-scan. CONCLUSIONS: In cataract patients whose posterior subscapular opacity is not severe, the accuracy for predicting refractive error after cataract surgery was not significantly different among the 3 devices included in our study (A-scan, IOL Master® and OA-2000®). However, in patients with severe posterior subscapular opacity, OA-2000®, that provides a Fourier domain light source-calculated predicted refractive error of IOL may be more accurate.