Nystagmus blockage syndrome in the unilaterally blind patient.

Those patients who have reduced vision in one eye and a variable esotropia should be suspected of having the nystagmus blockage syndrome. Typically such patients will have a head turn in the direction of the good eye with a preferred medial fixation point. Careful examination will reveal a nystagmus with the preferred position as the null point. Also, any patient who repeatedly has a recurrent esotropia after surgery should be suspected of having the nystagmus blockage syndrome. It is important to perform a posterior fixation suture with a recession on the medial recti of both eyes and to alter the null point by recessing the medial rectus more than 3 mm and resecting the lateral rectus appropriately for the head turn at the same surgical procedure. The eye with poor vision also should have the lateral rectus resected.