Spasmus nutans. A long-term follow-up.

PURPOSE

Nystagmus, head nodding, and anomalous head position are symptoms of spasmus nutans. This disorder appears in early childhood and is thought to be self-limited. However, the visual outcome of patients with spasmus nutans is unclear. The resolution of nystagmus has not been proven with quantitative eye movement recordings. The purpose of this study was to perform long-term follow-up examinations (mean, 5.5 years) of patients with spasmus nutans.

METHODS

Ten patients with spasmus nutans were followed up clinically until a mean age of 7 years. Included were quantitative eye and head movement recordings.

RESULTS

At their last examination (mean age, 7.1 years), visual acuity in four patients was 20/20 in both eyes, in five patients it was 20/30 or better in at least one eye, and in one patient it was 20/50 in each eye. Three patients had orthotropia with normal stereo acuity. The remaining patients had esotropia, dissociated vertical deviation, amblyopia, or latent nystagmus. All patients had fine, intermittent asymmetric, pendular nystagmus on eye movement recordings.

CONCLUSIONS

Good visual acuity can be expected in patients with spasmus nutans; one third have normal stereo acuity. However, subclinical nystagmus persists until at least 5 to 12 years of age.