Results of surgery to modify the null-zone position in congenital nystagmus.

The author reports the long-term (average 11 years) results of surgery to correct the face turn or tilt adopted to use the null zone associated with nystagmus. Of the 18 patients 16 had a face turn (7 with fusion and no strabismus, and 9 without fusion and strabismus) and 2 had a head tilt. Surgery was done after the age of 7 years (average 11 years), the same amount of surgery being done on all four horizontal rectus muscles in patients without strabismus to turn the eyes in the same direction as the face turn. Ten-millimetre recession/resection surgery produced the best correction of the face turn and the most gaze restriction. In patients with straight eyes before surgery strabismus was not produced or fusion or stereopsis lost. In patients with strabismus, surgery was modified on the nonfixing eye to correct the strabismus in addition to the face turn.