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Cochlear implants can be used to help restore severe hearing loss in children. The procedure was approved by the Food and Drug Administration for children in 1990. Electronic devices can restore children's sensitivity to sound, aiding in developing auditory, oral and social skills. Research about the effectiveness of this technique is ongoing, although the National Association of the Deaf objects to this procedure on ethical grounds.

If the cochlea, the hearing organ, is destroyed and segments of the auditory nerve (the sensory nerve associated with hearing) remain, cochlear implants may provide at least some hearing. The cochlear implant is an electrode system that is inserted into the bony cochlea of the ear; it requires electrical signals for stimulation. In many clinics the ability of the patient's nervous system to respond to cochlear stimulation is tested by direct electrical stimulation of the inner ear. One method is to place a small electrode on bone overlying the basal turn of the cochlea (the promontory, or portion of the cochlea that detects high frequency). This may be done through a small incision in the ear drum, or more recently, by simple perforation the ear drum with a small needle electrode, which is then brought into contact with the promontory. This paper discusses the use of a small ball-shaped electrode that is placed on the round window membrane, a thin partition enclosing a fluid-filled cavity of the inner ear (the perilymphatic space). Although this procedure uses slightly low-voltages to stimulate the inner ear, compared with the promontory electrode, the results were not significantly different. The use of a transtympanic needle electrode is less traumatic and the procedure is easier to perform. (Consumer Summary produced by Reliance Medical Information, Inc.)

When the cochlea, the hearing organ, is destroyed, but segments of the auditory nerve (the sensory nerve associated with hearing) remain, cochlear implants can often lead to the return of at least some hearing. The cochlear implant is an electrode system that is inserted into the bony cochlea and requires electrical signals for stimulation. The connection between the implant and the external circuitry required to operate the device can be achieved using a magnetic conduction in which a coil of wire is implanted under the skin and magnetically linked to a similar coil that is held over the skin. Another method is to make a direct connection between the electrode and the external circuitry. This method requires a stud or pedestal that is attached to the skull and passes through the skin. While the pedestal method is potentially the best electrical means of coupling the electrode to its driving circuitry, the possibility of infection at the site of the pedestal remains problematic. The present study reports the use of the percutaneous pedestal method in a group of 42 cochlear implant patients. The pedestal implants were well-tolerated by most, but not all, patients. In some patients, irritation at a implant site required one of the securing screws to be removed, which resolved the difficulty. Despite the potential possibility of infection at the site of the pedestal, the advantage afforded by a direct wiring contact between the cochlear electrode and external sound processing circuitry makes the percutaneous pedestal method attractive. (Consumer Summary produced by Reliance Medical Information, Inc.)

The age at which a child receives the first implant is an important factor that determines whether the second implant will be effective. Researchers at the University of Colorado at [...]