title: Cone beam computed tomography, a low-dose imaging technique in the postoperative assessment of cochlear implantation.
abstract: BACKGROUND
  Cone beam computed tomography (CBCT) has become an extremely useful technique for dentomaxillofacial imaging because it provides clear images of highly contrasted structures. Previous studies evaluating the applicability of this technique in otologic imaging were very encouraging but were only performed in vitro on temporal bone specimens. The intracochlear positioning of the individual electrodes after cochlear implantation by means of CBCT has not yet been shown in vivo.
  
  
  OBJECTIVE
  We describe a protocol for in vivo postoperative imaging of cochlear implants by CBCT. Moreover, the effective dose was measured and compared with the effective dose used on 4- and 16-slice multislice computed tomography (MSCT) by using a RANDO-phantom.
  
  
  METHODS
  Developing a protocol for in vivo postoperative imaging of cochlear implants by CBCT.
  
  
  RESULTS
  CBCT provides high-resolution and almost artifact-free multiplanar reconstruction images allowing assessment of the precise intracochlear position of the electrode and visualization of each of the individual contacts. The calculated effective dose of the used CBCT and MSCT acquisitions is 80 musv for the CBCT, 3,600 musv for the 16-slice computed tomography, and 4,800 musv for the 4-slice computed tomography.
  
  
  CONCLUSIONS
  These preliminary results suggests that, for in vivo postoperative evaluation of cochlear implants, CBCT can provide at least the same information as conventional radiography, digital radiograph, and MSCT but in a more comfortable and a much more safer way.
authors.affiliation: Hospital de Santa Maria, Lisbon, Portugal.
authors.forename: Joana
authors.initials: J
authors.lastname: Ruivo
authors.forename: Koen
authors.initials: K
authors.lastname: Mermuys
authors.forename: Klaus
authors.initials: K
authors.lastname: Bacher
authors.forename: Rudolf
authors.initials: R
authors.lastname: Kuhweide
authors.forename: Erwin
authors.initials: E
authors.lastname: Offeciers
authors.forename: Jan W
authors.initials: JW
authors.lastname: Casselman
mesh_terms: D000465:Algorithms; D016477:Artifacts; D003051:Cochlea / Q000000981:diagnostic imaging*; D003054:Cochlear Implants; D054893:Cone-Beam Computed Tomography / Q000009:adverse effects / Q000379:methods*; D005260:Female; D006801:Humans; D008297:Male; D008875:Middle Aged; D011829:Radiation Dosage; D013701:Temporal Bone / Q000000981:diagnostic imaging; D055815:Young Adult