Spasmus nutans (disease) true Spasmus nutans (SN) is a rare eye disease characterized by the clinical triad of asymmetric and pendular nystagmus, head nodding, and torticollis. MedDRA:10059593 UMLS:C1527306 MONDO:0017201 HP:0010533 SCTID:400948003 Spasmus nutans Orphanet:279882 ICD10:F98.4 This disorder of eye movement is seen in infants, typically with onset between 4 and 12 months of age. The cause is unknown; neuroimaging is required to exclude structural brain abnormalities. Vertical eye movements occur, these are rapid and side-to-side. There may be a head tilt and head nodding. The events resolve with time. Miscellaneous