Van Herick Angle Depth Estimation

Chamber Depth In Corneal Thickness	Angle Grade
≥ Cornea	4
1/4 to 1/2	3
1/4	2
<1/4	1
Slit	Dangerously Narrow

From: Van Herick W, Shaffer RN, Schwartz A. Estimation of width of angle of anterior chamber. Incidence and significance of the narrow angle. Am. J. Ophthalmol. 1969;68:626-629.