The Van Herrick test is a method used to estimate the depth of the anterior chamber angle in the eye.

What it’s for:

The Van Herrick test is used to:

1. Assess the risk of angle-closure glaucoma
2. Evaluate the anterior chamber angle width

How it’s done:

1. A narrow slit beam is shone onto the peripheral cornea.
2. The examiner observes the angle between the cornea and iris.
3. The width of the angle is estimated and graded.

Grading:

The Van Herrick test grades the angle as:

1. Grade 4: Wide open angle
2. Grade 3: Moderate angle
3. Grade 2: Narrow angle
4. Grade 1: Extremely narrow angle
5. Grade 0: Closed angle

What it shows:

The test helps identify patients at risk of angle-closure glaucoma, allowing for further evaluation and treatment if necessary.