Which test is most diagnostic for convergence insufficiency?

Which test is most diagnostic for convergence insufficiency?

• A. Near point of convergence (NPC) break value
• B. Color vision testing
• C. Saccadic velocity
• D. Pupillary response

Answer: (A)

Convergence insufficiency shows up most clearly when you test how far the eyes can converge for near tasks. The near point of convergence (NPC) test measures the distance at which the eyes can maintain single, fused vision as a target moves toward the nose. In convergence insufficiency, this break point is receded—that is, the patient loses fusion or sees diplopia sooner, at a greater distance. That direct measure of the eyes’ convergence ability makes NPC the best diagnostic tool for CI, because it directly reflects the vergence deficit central to the condition. The other tests assess functions that don’t reflect vergence ability. Color vision testing looks at chromatic discrimination, saccadic velocity checks how quickly the eyes can move from one target to another, and pupillary response evaluates pupil reactions. These can be normal in someone with convergence insufficiency and don’t specifically diagnose the convergence problem.

Convergence insufficiency shows up most clearly when you test how far the eyes can converge for near tasks. The near point of convergence (NPC) test measures the distance at which the eyes can maintain single, fused vision as a target moves toward the nose. In convergence insufficiency, this break point is receded—that is, the patient loses fusion or sees diplopia sooner, at a greater distance. That direct measure of the eyes’ convergence ability makes NPC the best diagnostic tool for CI, because it directly reflects the vergence deficit central to the condition.

The other tests assess functions that don’t reflect vergence ability. Color vision testing looks at chromatic discrimination, saccadic velocity checks how quickly the eyes can move from one target to another, and pupillary response evaluates pupil reactions. These can be normal in someone with convergence insufficiency and don’t specifically diagnose the convergence problem.