A patient has 8 CRXT and their subjective angle is 10 XT. What type of correspondence do they have?

• A. PAC 2
• B. Unharmonious correspondence
• C. HAC
• D. PAC 1

Answer: (A)

The key idea is that the brain’s way of mapping what each eye sees can shift in strabismus. When the eye movements (the objective motor angle) don’t line up with what the patient perceives (the subjective angle), it signals anomalous retinal correspondence. Here, the motor deviation is 8 prism diopters of exotropia, but the subjective perception shows 10 prism diopters exotropia. That 2-diopter difference indicates that the sensory map is only partly restructured to maintain fusion.

This pattern is labeled as partial anomalous correspondence, with the number indicating the degree of mismatch. A 2 diopter difference places it in PAC 2, meaning a moderate level of ARC where there’s some adapted mapping but not full normal alignment. Other classifications would imply different magnitudes or types of mismatch, so a small, specific difference like this fits PAC 2 best.