With the patient’s head immobilized, the examiner asks the patient to look in each of the nine diagnostic positions of gaze: 1, straight ahead; 2, right; 3, upper right; 4, up; 5, upper left; 6, left; 7, lower left; 8, down; and 9, lower right (Fig. 1.5). This allows the examiner to diagnose strabismus, paralysis of ocular muscles, and gaze paresis.
Evaluating the six cardinal directions of gaze (right, left, upper right, lower right, upper left, lower left) is sufficient when examining paralysis of the one of the six extraocular muscles. The motion impairment of the eye resulting from paralysis of an ocular muscle will be most evident in these positions. Only one of the rectus muscles is involved in each of the left and right positions of gaze (lateral or medial rectus muscle). All other directions of gaze involve several muscles.