title: Complications of the canalith repositioning procedure.
abstract: OBJECTIVE
  To describe the conversion of benign paroxysmal positional vertigo involving the posterior canal into benign paroxysmal positional vertigo involving the anterior or horizontal canals after treatment using the canalith repositioning maneuver.
  
  
  METHODS
  Retrospective study of outcome.
  
  
  METHODS
  Outpatient clinic.
  
  
  METHODS
  Consecutive sample of 85 patients diagnosed as having benign paroxysmal positional vertigo affecting the posterior canal. Identification of posterior canal involvement was based on the observation of the direction of the vertical component of nystagmus after the Hallpike-Dix maneuver.
  
  
  METHODS
  Canalith repositioning maneuver.
  
  
  METHODS
  Eye movements were observed about 1 week after the treatment. The direction of nystagmus elicited after movement of the patient into the Hallpike-Dix position indicated which canal was involved in the patients who had not responded to treatment.
  
  
  RESULTS
  Of the 85 patients studied who originally had posterior canal benign paroxysmal positional vertigo, five (6%) had anterior canal (n=2) or horizontal canal (n=3) positional vertigo after undergoing this maneuver.
  
  
  CONCLUSIONS
  Careful observation of the direction of the nystagmus is necessary for correct identification of which canal is involved in patients who do not respond to the initial treatment using the canalith repositioning maneuver.
authors.affiliation: Department of Otolaryngology, University of Miami School of Medicine, Florida, USA.
authors.forename: S J
authors.initials: SJ
authors.lastname: Herdman
authors.forename: R J
authors.initials: RJ
authors.lastname: Tusa
mesh_terms: D000328:Adult; D000368:Aged; D003937:Diagnosis, Differential; D005133:Eye Movements; D005260:Female; D006801:Humans; D009759:Nystagmus, Pathologic / Q000175:diagnosis / Q000503:physiopathology; D017063:Outcome Assessment, Health Care; D026741:Physical Therapy Modalities / Q000009:adverse effects; D011187:Posture; D012189:Retrospective Studies; D012399:Rotation; D012665:Semicircular Canals / Q000502:physiology*; D014717:Vertigo / Q000175:diagnosis / Q000209:etiology* / Q000628:therapy*