- Spasmus nutans is a triad of head tremor, nystagmus and torticollis. The condition usually begins in infancy (3-8 months)
- The head tremors are slow, can be horizontal or vertical. The nystagmus is low amplitude and high frequency pendular which increases when the child fixates at an object. Torticollis and head tremors are the compensatory mechanisms to dampen nystagmus.
- Differentials: Congenital nystagmus, retinal abnormalities and nystagmus in association with optic glioma. Congenital nystagmus begins in neonatal period or before 6 months of age and 90% of them have abnormal visual acuity.
Neuroimaging abnormalities described are optic nerve glioma, supra sellar tumor, cerebellar aplasia