A new method for gonioscopic grading of the anterior chamber angle

A method of gonioscopic grading of the anterior chamber angle is reported in which a linear scale is based on a unit that is the apparent combined width of the trabeculae and scleral spur. The scale indicates what proportion of the structures of the angle is gonioscopically visible. A within-observer trial of reliability indicates that the degree of precision inherent in the method is justified.