The Von Graefe test, also known as the Von Graefe’s prism test, is used to measure the amount of heterophoria (latent strabismus).

What it’s for:

The Von Graefe test is used to:

1. Measure heterophoria (latent strabismus)
2. Assess binocular vision

How it’s done:

1. The patient is asked to look at a target.
2. A prism is placed in front of one eye.
3. The prism is adjusted until the patient reports alignment of the target.
4. The amount of prism required to align the target measures the heterophoria.