Frisby Stereotest

The Frisby Stereotest is a simple and effective test to assess stereoscopic vision in children and adults. Stereoscopic vision, also called 3D vision, is the ability to perceive depth with both eyes. The Frisby stereo test was first launched in 1983 and is used worldwide in orthoptic and ophthalmology clinics and by optometrists.

The Frisby Stereotest

This Frisby stereotest allows you to easily perform a stereo test with natural vision, no glasses are required to perform the test. It has three transparent plates, which are presented to the patient one by one against the bright background of the fold-down lid of the storage box. The test can also be used if there is reduced vision or amblyopia due to the coarse textural elements in the pattern.

In stereopsis screening, the test objective is to discover whether the patient can reliably distinguish the circle-in-depth using the thickest test plate. Test subjects with stereopsis usually find the target quickly and confidently. Test subjects with defective stereopsis usually respond slowly and hesitantly with a high error rate.

Advantages

• No special glasses required: The test can be performed using the patient’s normal glasses.
• Suitable for young children: The test can be performed on children as young as 3 years old.
• Quick and easy: The test can be performed within minutes.
• Reliable results: The test is a reliable measure of stereoscopic vision.
• Clear: The test can also be used if there is reduced vision or amblyopia due to the coarse textural elements in the pattern.

The Frisby Stereotest consists of:

• Three transparent plates of different thicknesses
• A storage box with fold-out flap for a clear background
• Measuring tape for checking the distance between eye and plate

Testprocedure stereotest

1. Have the patient sit in a chair at the examiner’s eye level.
   When testing, the plates should be raised a few cm above the background
2. Hold the plate with the largest thickness in front of the patient and ask him/her to point to the circle in the center that appears to protrude furthest.
3. Repeat step 2 with the smaller thickness plates.
4. Record the distance between eye and plate for each plate.

Interpret the results

The results of the test are used to assess the patient’s stereoscopic vision. The smaller the distance between eye and plate, the better the patient’s stereoscopic vision.