What will Undergoing Cochlear Implant Surgery Involve?
To fully understand cochlear implant surgery, some knowledge of the associated device can be helpful. Although the suitability of each candidate for this procedure is reviewed in depth, basically, it is applicable to those with profound sensorineural deafness that are unable to benefit from a conventional hearing aid. In these devices, external components capture sound with a microphone and relay it to a sound processor, where it is converted to a digital signal and passed to a headpiece transmitter held in place magnetically by a receiver beneath the skin. The received digitised signal is converted to electrical impulses and a connected electrode array stimulates the auditory nerve directly.
That said, it is clear that cochlear implant surgery will be required, in order to position both the receiver and the attached electrode array components that comprise the internal part of the device. Prior to the operation, each prospective candidate is evaluated and while the criteria to be met may vary, the procedure is suitable for both adults who have lost their hearing and for infants born without the ability to hear. Other pre-operative measures will include physical inspection of the ear for signs of infection, checking for any potential problems with anaesthesia and either CT or MRI scans to get a clearer picture of the inner ear anatomy.
Although often undertaken as an outpatient procedure, cochlear implant surgery, especially in the case of infants, may require admission. It is conducted under general anaesthetic and begins with an incision behind the ear prior to creating an opening in the mastoid bone that is necessary to provide the surgeon with access to the middle ear space. This done, the next step is to make an opening in the cochlear window through which the electrode array may then be inserted. The final step in the procedure will be to connect the array to the receiver and position it beneath the skin before closing the incision.
The operation will normally be completed within 2 to 3 hours and, following cochlear implant surgery, most patients report feeling well within one to two days, and can generally resume school or work after a week or two at the most. There are some associated risks, although their incidences are quite low. Apart from those associated with anaesthesia, these include possible post-op infections, accidental damage to the facial nerve, a feeling of numbness around the ear and tinnitus. Any increased risk of meningitis is avoidable with pre-operative vaccination.
The procedure only positions the internal components of the auditory prosthesis, so patients should not expect to awake with their hearing restored following their cochlear implant surgery. A recovery period of 3 to 6 weeks will be required to ensure all swelling and tenderness in the operation site has subsided and, only then, will the external components be connected. Once connected and initial adjustments are made, a period of training and further adjustments, serve to help in the interpretation of the new sound sensations. Better than nine out of ten will quickly learn to discern and understand speech with no need for visual clues, while the remainder will find a marked reduction in their dependence on lip reading.
Overall, the many pros far outweigh the few cons for those who choose cochlear implant surgery.