Comparative analysis of white-to-white and angle-to-angle distance measurements with partial coherence interferometry and optical coherence tomography

Purpose: To perform white-to-white (WTW) and angle-to-angle (ATA) distance measurements with 2 optical devices and analyze the correlation with other anterior segment parameters.

Setting: Department of Ophthalmology, Medical Health and Science Center, University of Debrecen, Debrecen, Hungary.

Design: Comparative case series.

Methods: In this prospective study, the WTW distance, axial length (AL), and anterior chamber depth (ACD) were measured by partial coherence interferometry (PCI) (IOLMaster). The horizontal and vertical ATA distances and ACD were assessed by anterior segment optical coherence tomography (AS-OCT) (Visante).

Results: The mean PCI values were AL, 23.31 mm ± 1.52 (SD); WTW distance, 11.99 ± 0.47 mm; ACD, 2.99 ± 0.4 mm. On AS-OCT, the mean horizontal ATA was 11.43 ± 0.51 mm and the mean vertical ATA, 10.72 ± 0.66 mm. The WTW distance was significantly greater than the horizontal ATA distance, and the horizontal ATA distance was significantly greater than the vertical ATA distance (P<.0001). The correlations between WTW and horizontal ATA (r = 0.51; P<.0001), vertical ATA (r = 0.32; P<.0021), AL (r = 0.45; P<.0001), and patient age (r = -0.28; P = .023) were significant. The PCI WTW distance and ACD were significantly correlated (r = 0.55; P<.0001). There were no significant correlations between AS-OCT horizontal and vertical ATA measurements (r = -0.02; P = 0.79) or between same-device ACD measurements (r = 0.18; P = .15).

Conclusions: Although PCI WTW and AS-OCT ATA measurements are not clinically interchangeable, the WTW values correlated well with horizontal and vertical measurements and other anterior segment parameters.