Hostname: page-component-78c5997874-94fs2 Total loading time: 0 Render date: 2024-11-13T03:58:22.946Z Has data issue: false hasContentIssue false

Radiology for cochlear implants

Published online by Cambridge University Press:  29 June 2007

R. F. Gray*
Affiliation:
Cambridge
R. A. Evans
Affiliation:
Cambridge
C. E. L. Freer
Affiliation:
Cambridge
H. E. Szutowicz
Affiliation:
Cambridge
G. F. Maskell
Affiliation:
Cambridge
*
Mr. R. F. Gray F.R.C.S., Department of Otolaryngology, Addenbrooke's Hospital, Cambridge CB2 2QQ, UK.

Abstract

One fifth of patients selected for cochlear implants have such bony irregularities in the cochlear duct that full insertion of a multichannel electrode array is impossible. Three cases of cochlear deafness are presented where pre- and post-operative radiology played an important part in the management.

Standard CT at 2 mm cuts is compared with ultra high resolution CT at 1 mm cuts. The pitfall of poor definition is that the inexperienced surgeon may find himself unexpectedly drilling out an obliterated cochlear duct. Sections 30 degrees caudal to Reid's infra orbito-meatal base line at 1 mm intervals give maximum information for minimum radiation.

Plain films show the placement of individual platinum electrode contacts in relation to the spiral ‘frequency map’ of the cochlea. This is vital information for the audiologist who has to route specific frequencies to specific sites within the ear for a good hearing result.

Type
Main Articles
Copyright
Copyright © JLO (1984) Limited 1991

Access options

Get access to the full version of this content by using one of the access options below. (Log in options will check for institutional or personal access. Content may require purchase if you do not have access.)

Footnotes

Paper presented at the Second International Implant Symposium, Iowa City, 4-9 June 1990.

References

Balkany, T, Gantz, B, Nadol, J. B. (1988) Multichannel cochlear implants in partially ossified cochleas. Annals of Otology, Rhinology and Laryngology, 97: pp. 37.CrossRefGoogle Scholar
Ball, J. B., Miller, G. W., Hepfner, S. T. (1986) Computed tomography of single-channel cochlear implants. American Journal of Neuroradiology, 7: 4147.Google ScholarPubMed
Chakeres, D. W., Kapila, A. (1984) Computed tomography of the temporal bone. Medical Radiography and Photography, 60: pp 10 and 14.Google ScholarPubMed
Harnsberger, H. R., Dart, D. J., Parkin, J. L., Smoker, W. R., Osborn, A. G. (1987) Cochlear implant candidates: assessment with CT and MR imaging. Radiology, 164: 5357.CrossRefGoogle ScholarPubMed
Jackler, R. K., Luxford, W. M., Schindler, R. A., McKerrow, W. S. (1987) Cochlear patency problems in cochlear implantation. Laryngoscope, 97: Part 1 801805.CrossRefGoogle ScholarPubMed
Kotzias, S. A., Linthicum, F. H. Jr, (1985) Labyrinthine Ossification: Differences between two types of ectopic bone. American Journal of Otology, 6: 490494.Google ScholarPubMed
Laszig, R., Terway, B., Battmer, R. D., Hesse, G. (1988) Magnetic resonance imaging (MRI) and high resolution computer tomography (HRCT) in cochlear implant candidates. Scandinavian Audiology Supplement, 30: 197200.Google Scholar
Phelps, D. P., Annis, J. A. D., Johnson, P. J. (1990) Imaging for cochlear implants. British Journal of Radiology, 63: 512516.CrossRefGoogle ScholarPubMed
Rosenberg, R. A., Cohen, N. L., Reede, D. L. (1987) Radiographic imaging for the cochlear implant. Annals of Otology, Rhinology and Laryngology, 96: 300304.CrossRefGoogle ScholarPubMed
Tucci, D. L., Lambert, P. R., Ruth, R. A. (1990) Trends in rehabilitation after cochlear implantation. Archives Otolaryngology, Head and Neck Surgery, 116: 571574.CrossRefGoogle ScholarPubMed