Abstract
Purpose: :
To evaluate the precision, repeatability of Ciliary Sulcus Diameter measurements by Panoramic Ultrasound Biomicroscopy
Methods: :
One human eyeball for precision evaluation was obtained from eye bank of Beijing Tongren Eye Center within 24 hours of death. A needle with fluted scale was insert through the posterior chamber plane from 3 o’clock to 9 o’clock meridian,needle images were obtained by Panoramic Ultrasound Biomicroscopy. The measurement precision was analysed by comparing image scale valve with true scale value. One randomly selected eye of thirty normal subjects were enrolled in the study for repeatability evaluation of intraobserver and interobserver. Horizontal and vertical ciliary sulcus diameters were measured 3 times by one operator and 1 time by another operator.
Results: :
The geometric precision of the measurement in human eye was less than 4 %. The deviation to actual measurement scale was only 70µm to the greatest extent, the error rate was 0.64%.Repeatability evaluation showed that the coefficient of variation was 0.38%; Coefficients of repeatability for intraobserver and interobserver measurements were 1.99% and 2.55%, respectively. The limits of agreement for intraobserver and interobserver measurement were -0.4108 to 0.4881 mm and -0.5862 to 0.5782 mm, respectively. The vertical Ciliary Sulcus diameters were (12.067±0.94mm) greater than horizontal diameters(11.538±0.92mm) significantly (P=0.000).
Conclusions: :
Panoramic UBM could get the whole cross-section image of the anterior segment with high accuracy and good repeatability.
Keywords: imaging methods (CT, FA, ICG, MRI, OCT, RTA, SLO, ultrasound) • anterior segment