Proximal effects of using the Maddox rod can cause the patient to appear to have which misalignment?

Proximal effects of using the Maddox rod can cause the patient to appear to have which misalignment?

• A. Exo
• B. No effect
• C. Eso
• D. Hypotropia

Answer: (C)

Proximal cues—the perceived closeness of the target—drive the eyes to converge more. When using a Maddox rod, one eye sees a line and the other eye sees a point, so the perceived alignment depends on the vergence state. At near fixations, the demand for convergence increases, pulling the eyes inward. This enhanced convergence makes the apparent alignment shift toward an inward deviation, so the patient looks like they have esotropia. This is a proximal, perceptual effect during the test, not a fixed, constant misalignment.

Proximal cues—the perceived closeness of the target—drive the eyes to converge more. When using a Maddox rod, one eye sees a line and the other eye sees a point, so the perceived alignment depends on the vergence state. At near fixations, the demand for convergence increases, pulling the eyes inward. This enhanced convergence makes the apparent alignment shift toward an inward deviation, so the patient looks like they have esotropia. This is a proximal, perceptual effect during the test, not a fixed, constant misalignment.