Cochlear Implant Complications Are Rare-But Can Be Lethal

When a cochlear implant patient presents with ear pain and otitis media in the same ear as the implant, the clinician should be diligent in examining for signs of meningitis, such as fever, stiff neck, and lethargy. Any patient suspected of having meningitis should go to the ER for a lumbar puncture and be started on intravenous antibiotics, Dr. Megerian said. Immunization against S. pneumoniae and H. influenzae is used to prevent meningitis.

Dr. Megerian cautioned that even in the absence of signs of meningitis, any infection in the same ear as the implant should be treated aggressively. Once a person has had an implant, you need to be aggressive. The risk of meningitis is small, but it is a serious complication, he stated.

Less Worrisome Complications

Dr. Megerian was co-author of a recent review of complications of cochlear implants (Tambyraja RR et al. Arch Otolaryngol Head Neck Surg 2005;131:245-50), which was based on the FDA’s Manufacturer and User Facility Device Experience (MAUDE) database. He and his colleagues studied two time periods: pre-1998 and the year 2002. The most common complication to occur during both time periods was device failure: 74/129 (57%) pre-1998 and 267/654 (41%) in 2002. Device failure should be suspected if a patient reports that the implant has stopped working, or that he or she felt a shock. The otolaryngologist needs to make sure the device is turned on; then the patient should be referred to the cochlear implant team. If the implant stops working over time, it can be replaced, Dr. Gianoli noted.

Other complications include wound/scalp/flap problems at the site of implant. These can take two forms: implant extrusion or the flap pulling apart and becoming vulnerable to infection. Again, Dr. Megerian emphasized the need for aggressive treatment with intravenous antibiotics at any sign of infection.

The good news is that from 1998 to 2002, the rate of wound flap problems was reduced. This is likely due to the movement toward a smaller incision, Dr. Megerian commented.

Other complications may include pain in the area over the magnet. The skin may be pulled too tight and cause redness in the magnet area. This would signal the need for a weaker magnet, Dr. Megerian said, which would prevent a scalp infection down the line.

Facial nerve injury is a very rare occurrence, but facial nerve stimulation by the device is fairly common in patients with a cochlear implant, said Dr. Gianoli. The electrode goes through the facial recess, and the current can stimulate the facial nerve. This is easily handled and does not impair the success of the procedure, he observed. If there is evidence of facial nerve stimulation, the audiologist who programs the implant can turn off one or two of the electrodes, which usually solves the problem. Explantation and implantation are rarely necessary, Dr. Gianoli said.