title: Head-Jolting Nystagmus: Occlusion of the Horizontal Semicircular Canal Induced by Vigorous Head Shaking.
abstract: OBJECTIVE
  We report a new syndrome, which we are calling head-jolting nystagmus, that expands the differential diagnosis of head movement-induced paroxysmal vertigo.
  
  
  METHODS
  Two male patients (65 and 58 years old) described rotational vertigo after violent and brief (1- to 2-second) oscillations of the head (head jolting) that triggered intense horizontal nystagmus lasting 45 seconds. Accelerations of the head required to induce these episodes could only be achieved by the patients themselves. In case 1, the episodes gradually disappeared over a 6-year period. In case 2, magnetic resonance imaging (3-T) suggested a filling defect within the left horizontal semicircular canal. He underwent surgical canal plugging in March 2013 that resolved the symptoms.
  
  
  CONCLUSIONS
  We attribute head-jolting nystagmus to dislodged material within the horizontal semicircular canal and provide a mechanistic model to explain its origin.
authors.affiliation: Neuro-otology Unit, Division of Brain Sciences, Imperial College London, London, England2Department of Neuro-otology, National Hospital for Neurology and Neurosurgery, University College London, London, England.
authors.forename: Adolfo M
authors.initials: AM
authors.lastname: Bronstein
authors.affiliation: Neuro-otology Unit, Division of Brain Sciences, Imperial College London, London, England2Department of Neuro-otology, National Hospital for Neurology and Neurosurgery, University College London, London, England.
authors.forename: Diego
authors.initials: D
authors.lastname: Kaski
authors.affiliation: Neuro-otology Unit, Division of Brain Sciences, Imperial College London, London, England3Department of Medicine, University of Otago, Otago, New Zealand.
authors.forename: Nick
authors.initials: N
authors.lastname: Cutfield
authors.affiliation: Neuro-otology Unit, Division of Brain Sciences, Imperial College London, London, England.
authors.forename: David
authors.initials: D
authors.lastname: Buckwell
authors.affiliation: Ear, Nose and Throat Department, University Hospital Birmingham, Birmingham, England.
authors.forename: Rupan
authors.initials: R
authors.lastname: Banga
authors.affiliation: Ear, Nose and Throat Department, Sheffield Teaching Hospitals, Sheffield, England.
authors.forename: Jaydip
authors.initials: J
authors.lastname: Ray
authors.affiliation: Ear, Nose and Throat Department, University Hospital Birmingham, Birmingham, England.
authors.forename: Swarupsinh
authors.initials: S
authors.lastname: Chavda
authors.affiliation: Ear, Nose and Throat Department, University Hospital Birmingham, Birmingham, England.
authors.forename: Richard
authors.initials: R
authors.lastname: Irving
mesh_terms: D000368:Aged; D065635:Benign Paroxysmal Positional Vertigo / Q000175:diagnosis* / Q000209:etiology; D019416:Head Movements; D006801:Humans; D008297:Male; D008875:Middle Aged; D009759:Nystagmus, Pathologic / Q000175:diagnosis* / Q000209:etiology; D012665:Semicircular Canals; D013577:Syndrome