To compare the results of anterior segment biometry including white-to-white (WTW) between scanning-slit topography (ORBscan IIz®, Bausch & Lomb), optical low-coherence reflectometry (OLCR) biometry (Lenstar®, Haag-Streit), and Castroviejo calipers.

Measurements on 72 eyes of 36 patients that underwent refractive surgery were measured using ORBscan®, Lenstar®, and calipers and compared. Ocular biometry parameters used in this study included the WTW, central corneal thickness, anterior chamber depth (ACD), keratometry, and pupil size.

The WTW measurements using ORBscan® and calipers (11.57 ± 0.35 mm and 11.58 ± 0.34 mm, respectively) were statistically similar. However, the measurement using Lenstar® (12.05 ± 0.40 mm) was significantly greater than with the other methods ( p < 0.001). Central corneal thickness and keratometry measurements using ORBscan® were greater than when using Lenstar® ( p = 0.01 for both). ACD and pupil size measurement using Lenstar® were greater than when using ORBscan® ( p < 0.001 for both).

Because WTW and ACD measurements using Lenstar® were greater than when using ORBscan® and calipers, unexpected high-vaulting may be observed due to the selection of a larger-sized posterior chamber phakic intraocular lens. Therefore, the differences in measurements obtained when using these methods should be considered.