title: Positional vertigo and cochlear implantation.
abstract: OBJECTIVE
  To identify patients developing positional vertigo after cochlear implantation.
  
  
  METHODS
  Prospective study on a cohort of patients undergoing cochlear implantation.
  
  
  METHODS
  Academic tertiary referral center.
  
  
  METHODS
  The study included 70 consecutive patients who underwent vestibular evaluation before and after cochlear implantation.
  
  
  METHODS
  Medical record review.
  
  
  METHODS
  Recorded vestibular symptoms after cochlear implantation. Patients with positional vertigo were considered case subjects, whereas those without vestibular symptoms were considered case controls.
  
  
  RESULTS
  Benign paroxysmal positional vertigo (BPPV) occurred in 8 patients (on the cochlear implant [CI] side in 7 patients, and in the other ear in 1). One patient had BPPV of the lateral semicircular canal on the implanted side, and 7 patients had BPPV of the posterior semicircular canal (on the same CI side in 6 patients, and on the opposite side in 1), which were detected and presented during the last examination. In 5 patients, the onset of symptoms varied from 7 to 130 days after implant activation; in 2 patients, the onset occurred before activation.
  
  
  CONCLUSIONS
  Three different mechanisms are proposed for the occurrence of BPPV in patients with CI. The first focuses on the fall of bone dust particles into the cochlea during cochleostomy. In the second, the vibration caused by drilling the cochlea would be sufficient to dislodge otoconia into the labyrinth. The third hypothesis suggests dislodging of an otolith because of the electric stimulation. In our patients, conservative approaches have been used with a minimal invasive cochleostomy and without perilymph suction. Thus, the vibratory trauma affecting the cochlea during cochleostomy seems to play a fundamental role in the development of paroxysmal vertigo in patients with implant.
authors.affiliation: E.N.T. Department, The University La Sapienza, Rome, Italy. marikaviccaro@tiscali.it
authors.forename: Marika
authors.initials: M
authors.lastname: Viccaro
authors.forename: Patrizia
authors.initials: P
authors.lastname: Mancini
authors.forename: Raffaella
authors.initials: R
authors.lastname: La Gamma
authors.forename: Elio
authors.initials: E
authors.lastname: De Seta
authors.forename: Edoardo
authors.initials: E
authors.lastname: Covelli
authors.forename: Roberto
authors.initials: R
authors.lastname: Filipo
mesh_terms: D000293:Adolescent; D000368:Aged; D019929:Cochlear Implantation / Q000009:adverse effects*; D015331:Cohort Studies; D005260:Female; D007839:Functional Laterality / Q000502:physiology; D006801:Humans; D008297:Male; D008875:Middle Aged; D011446:Prospective Studies; D012665:Semicircular Canals / Q000502:physiology; D016896:Treatment Outcome; D014717:Vertigo / Q000209:etiology*; D014724:Vestibular Function Tests