Posttraumatic convergence insufficiency.

Convergence insufficiency was encountered following closed head trauma in 23 patients. The most common complaints included difficulty reading and diplopia at near. The severity of the head trauma varied. There was no correlation between the severity of the head trauma and the severity of the convergence insufficiency. A normal near point of convergence was encountered in six of the 23 patients; all six patients had abnormal convergence reserves when measured with prisms. Treatment consisted primarily of convergence exercises and prisms. Bilateral medial rectus resections were required in two patients. Response to therapy was variable and often incomplete. The anatomic localization of convergence insufficiency secondary to head trauma remains unknown, although lesions in the occipital lobe and upper midbrain both seem capable of producing this syndrome.