Abduction nystagmus

An eight-year-old patient was seen with esotropia, a head turn to the right and nystagmus, more pronounced in abduction with either eye fixing. The fast phase of nystagmus was towards abduction of the fixing eye. In marked adduction (45°), the direction of the fast phase of nystagmus was seen to reverse. The frequency of nystagmus was not affected by eye position or by which eye was fixing.Following recession of each medial rectus muscle the esotropia was eliminated. An interesting but unexplained postoperative finding was that the amplitude of nystagmus was greatest in the primary position only with fixation by the opposite eye.