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

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

Answer: (A)

The concept being tested is how to interpret retinal correspondence by comparing motor and sensory measurements of deviation. When the objective angle of deviation and the subjective angle reported by the patient are essentially the same (within a small tolerance), the sensory and motor systems are aligned, indicating normal retinal correspondence and a PAC 1 pattern.

Here, the motor deviation is about 8 prism diopters of exotropia, and the patient’s subjective angle is 10 prism diopters exotropia. The two values are very close and in the same direction, which fits concordant sensory-motor mapping. That alignment corresponds to PAC 1.

If there were a larger mismatch or a different pattern (e.g., a significant discrepancy indicating anomalous retinal correspondence or unharmonious correspondence, or another pattern labeled HAC), those would point to a different category.