Post-operative return of head malposition in congenital null point nystagmus.

We present two patients with congenital null point nystagmus with head malposition and orthotopic eyes who underwent a modified Kestenbaum-Anderson operation. The face malposition returned in both patients about one year post operatively despite marked reduction of gaze toward the side of the original null point. We do not believe it is the reduced adduction of the fixating eye that eliminates the face turn or prevents its recurrence. Surgical normalization of an abnormal proprioception eliminates the face turn whereas the head malposition return is due to a faulty development of the brain, irreversible and deeply adopted to the abnormal proprioception.