Determination of Anterior Chamber Volume: Agreement Between Pentacam and the Wang Formula for Visante OCT

Abstract

Purpose: : To evaluate the level of agreement between anterior chamber volume (ACV) measurements obtained with Pentacam and measurements obtained with the Wang formula for Visante-OCT.

Methods: : Volunteers with no anterior segment disease were recruited. Visante ACV measurements were obtained by means of the methodology proposed by Wang N. et al in 2007. A Bland-Altman analysis was performed to assess agreement between measurements with Pentacam and Visante-OCT.

Results: : One randomly selected eye from 30 participants was analysed. Spherical equivalent ranged between -2.50 D and +1.50 D. Mean±SD age was 56.3 ± 17.4 years with a range from 25 to 79 years. Mean±SD Pentacam ACV was 171.07 ± 39.64 µl (Vmin=103 µl and Vmax= 236 µl), while mean±SD Visante ACV was 171.38 ± 42.38 µl (Vmin=96.37 µl and Vmax= 245.54 µl). The mean difference between measurements was -0.318 and the 95% limits of agreement were -11.09 and 11.09. The differences between measurements were within the 95% limits of agreement in all but one eye.

Conclusions: : High levels of agreement were found between anterior chamber volume measurements obtained with Pentacam and measurements obtained with Visante-OCT when the Wang formula was used.

Keywords: anterior chamber • topography • imaging methods (CT, FA, ICG, MRI, OCT, RTA, SLO, ultrasound)