The purpose of the cochlear implant surgery is for improvement of hearing so that one can be easy to connect with other people and ameliorating quality of life, including language and mental development, learning, communication and social ability.
Children who have congenital severe to profound hearing loss causing problems of language learning and speech understanding or adult who have moderately-severe to profound bilateral sensorineural hearing loss with few or no useful benefit from hearing aids could be patient candidacy with consideration for cochlear implant surgery.
Cochlear implant is indicated in moderate to severe hearing handicapped. The modern cochlear implant is a device designed to receive environmental sound (receiver-stimulator) then convert into electrical impulses that are delivered along a multiple electrode array(electrode) situated in close proximity to the cochlear (auditory) nerve. As this paradigm does not necessarily rely upon hair cell transduction mechanisms, it is ideal for patients with significant hair cell loss.
Complete pre-operative examination will be conducted, including pure tone audiometry, speech discrimination test, sound field audiometry, auditory brain stem response, otoacoustic emission, etc. High resolution computerized tomography helps determine the better ear for implantation, and magnetic resonance imaging will also be arranged to rule out the possibility of acoustic neuroma if necessary. The process of operation is under general anesthesia. At first, postauricular incision will be made. After elevation of the skin and scalp, drilling out of the skull followed by placement of the receiver-stimulator will be done. Then performing mastoidectomy and posterior tympanotomy till expose of round window niche clearly. Finally, insertion of electrode after cochleostomy is completed. After the surgery, the radiograph should be obtained to document intracochlear placement of the electrode.
Risks & complications
- Postoperative infection
Since the implant will be placed in the body permanently, there is risk for infection. However, prescription of proper antibiotics will reduce the risks.
- Facial paralysis
The facial nerve will possibly be encountered during surgery. If injury of the nerve is happened, transient or long-term unilateral paralysis of face will be noted. However, this event could be avoided by experienced operator and using facial nerve monitor.
- Cerebrospinal fluid (CSF) leakage
Though little possibility, rupture of dura might be happened and it would cause cerebrospinal fluid leakage. Repair of dura with autologous soft tissue and nonautologous glue will solve this problem during operation.
- Device failure
The implant is not functional well because of integrated etiology, such as anatomy, age of the patient, previous medical underlying, etc.
The procedure cost is about 1,100,000 NTD; prices are subject to change without prior notice, and need to pay in accordance with the actual medical expenses.