Corneal radii and anterior chamber depth measurements using the IOLMaster versus the Pentacam

PURPOSE: Corneal radii (R1, R2) and anterior chamber depth are important parameters for biometry and refractive surgery. This study aimed to investigate whether the IOLMaster, a biometric device, and the Pentacam, a rotating Scheimpflug camera, provide comparable results. METHODS: In this prospective study, corneal radii and anterior chamber depth were analyzed in 82 eyes of 41 phakic patients (median age 72 years) using the IOLMaster and Pentacam. Normal distribution was confirmed using the Kolmogorov-Smimov test. A paired t test was used for statistical. analysis. RESULTS: No statistically significant difference was noted for R2 using the Pentacam versus the IOLMaster (P=.40). There was a small statistical difference of 0.03 mm (P <.01) for R1 (corresponding to 0.08 diopters [D]). The IOLMaster measured a mean R1 of 7.87 mm and R2 of 7.67 mm. The Pentacam measured mean R1 of 7.90 mm and R2 of 7.69 mm. For anterior chamber depth values, a small statistically significant difference of 0.05 mm (P <.001) was found (corresponding to 0.01 D). Mean anterior chamber depth measured from the epithelium was 3.20 mm for the IOLMaster and 3.25 mm for the Pentacam. The Bland-Altman plot showed no distorting trends for either variable. CONCLUSIONS: Keratometry and anterior chamber depth were comparable for the two devices. If the axial length is known, the Pentacam can be used as a biometric device.