Abstract
Purpose: :
The PENTACAMTM (Oculus,Germany) is a device utilizing the Sheimplug images for non–invasive evaluation of corneal topography, corneal thickness and the three dimensional structures of the anterior chamber (AC). We investigated the reproducibility of PENTACAMTM measurements of the AC structure and its correlation with gonioscopic angle grading and anterior chamber angle (AC angle) measured by ultrasound biomicroscopy (UBM).
Methods: :
Two consecutive PENTACAMTM measurements were made at intervals of 3 minutes on 52 eyes of 30 subjects with an angle narrower than the Schaffer grade 2 by gonioscopy in at least one quadrant. Reproducibility of measurement results of the AC depth, volume and the narrower angle of the nasal and temporal angle, and their correlations with gonioscopic angle grading, UBM AC angle measurements and axial length by A–mode scan were studied.
Results: :
The reproducibility indexes of AC volume, depth and angle measurements were sufficient for clinical use (1.2±1.3%, 2.4±2.4%, 9.8±12.5%, mean±SD, N=52 respectively). No significant correlation between PENTACAMTM measurements and gonioscopic angle grading were found (AC depth: R=0.34, p=0.37, AC volume: R=–0.14, p=0.58, nasal or temporal AC angle: R=0.07, p=0.97), while AC volume showed significant correlation with axial length (R=0.37, P=0.01). The narrower of the nasal or temporal AC angle measured by PENTACAMTM and UBM averaged 26.78±5.55, and 9.62±0.32 respectively, and no correlation between them was observed (R=0.02, p=0.89)
Conclusions: :
Reproducibility of PENTACAMTM measurements of the anterior chamber structure was satisfactory in narrow angle eyes, suggesting clinical usefulness of this new instrument. AC angle measured with PENTACAMTM, however, showed no correlation with gonioscopic angle grading or that by UBM in narrow angle eyes, which limits application of PENTACAMTM for evaluation of AC angle in narrow angle eyes.
Keywords: imaging methods (CT, FA, ICG, MRI, OCT, RTA, SLO, ultrasound) • anterior chamber