Assessment of measurement variability across automated biometry devices.

Abstract

Purpose: To evaluate measurement variability between different readily available automated biometric devices for the purposes of improving surgeon decision-making for phakic intraocular lens (IOL) sizing.

Setting: Private practice (Houston, Texas).

Design: Prospective, single-center, bilateral, nonrandomized, open-label, observational study.

Methods: This study included healthy eyes, with no prior eye surgery, and with a spherical equivalent of at least -1.00 diopter. Orbscan II was compared with Argos, Atlas 9000, caliper, IOLMaster 500, IOLMaster 700, iTrace, Lenstar LS900, Pentacam HR, and Pentacam AXL Wave. Preoperative measurements included white-to-white (WTW), anterior chamber depth (ACD), and central corneal thickness (CCT). Linear mixed-effect models were created to determine adjustment factor between the Orbscan II and other devices for WTW, ACD, and CCT measurements.

Results: 204 participants (408 eyes) completed the study. All mean WTW measurements were significantly different compared with the Orbscan II ( P < .01), except for Pentacam AXL Wave. All mean ACD and CCT measurements were significantly different compared with the Orbscan II ( P < .01). Adjustment factors for WTW ranged from -0.65 to 0.24 mm. Adjustment factors for ACD ranged from -0.21 to -0.16 mm. Adjustment factors for CCT ranged from 19.9 to -36.0 μm.

Conclusions: The biometers tested were not interchangeable with the Orbscan II. Adjustment factors for WTW and ACD may compensate for differences between devices and adapt ICL sizing recommendations.