Quantitative ultrasound biomicroscopy of iridocorneal angle

Background: Ultrasound biomicroscopy (UBM) is a high-resolution ultrasound technique, which allows noninvasive, in vivo imaging of the ocular anterior segment structures. Purpose: This video gives a description of the identification of the iridocorneal angle structures in the cross-sectional view in a radial scan through a typical ciliary process and a guide toward measuring the angle parameters. Synopsis: UBM provides two-dimensional, grayscale images of the iridocorneal angle. The real-time image is displayed on a video monitor and can be recorded for qualitative and quantitative analysis. The angle parameters can be measured by in-built calipers in the machine software and manipulated by the examiner. Highlights: This video demonstrates UBM caliper positions as displayed on the monitor and marked by the examiner for the measurement of various anterior segment parameters of the eye. Video link: https://youtu.be/WTXMupYoyww. Key words: Angle parameters, quantitative measurements, UBM