What information does the Worth 4-dot test provide in binocular vision assessment?

What information does the Worth 4-dot test provide in binocular vision assessment?

• A. It measures stereoacuity at near.
• B. It detects color vision defects.
• C. It reveals suppression patterns on each eye.
• D. It reveals suppression, diplopia, and fusion status.

Answer: (D)

How the two eyes work together is being tested here. The Worth 4-dot test uses red-green glasses and a target with red, green, and two white dots to see which eye is contributing to vision and whether the images fuse or appear double. The colors map to each eye (each eye sees only its colored dot, while the white dots are seen by both eyes). By asking what the patient sees, you can tell if both eyes are fusing into a single image, if one eye’s image is being suppressed, or if double vision is present. Seeing four dots means fusion with no suppression; seeing a pattern that reflects only one eye’s dots suggests suppression of the other eye; reporting two different images indicates diplopia. So the test provides information about suppression, diplopia, and fusion status. It does not assess color vision defects or stereoacuity directly.

How the two eyes work together is being tested here. The Worth 4-dot test uses red-green glasses and a target with red, green, and two white dots to see which eye is contributing to vision and whether the images fuse or appear double. The colors map to each eye (each eye sees only its colored dot, while the white dots are seen by both eyes). By asking what the patient sees, you can tell if both eyes are fusing into a single image, if one eye’s image is being suppressed, or if double vision is present. Seeing four dots means fusion with no suppression; seeing a pattern that reflects only one eye’s dots suggests suppression of the other eye; reporting two different images indicates diplopia. So the test provides information about suppression, diplopia, and fusion status. It does not assess color vision defects or stereoacuity directly.