Effect of simultaneous exercise and noise exposure (music) on hearing.

Hearing thresholds were measured in 12 subjects prior to and following their participation in three experimental conditions: (a) riding a cycle ergometer for 20 minutes; (b) listening to a selection of music at an equivalent intensity of 96 dB(A) SPL for 20 minutes; and (c) listening to the music while riding the cycle ergometer for 20 minutes. Analysis of the results shows a measurable and statistically greater noise-induced temporary threshold shift (NITTS) for the music plus exercise condition that for either of the other two conditions. The greatest differences were seen in the 3-6 kHz frequency range. These results suggest an increased susceptibility to NITTS and, by extension, to increased potential for permanent hearing loss when noise exposure is coupled with exercise. The results have implications related to contemporary lifestyle issues such as aerobics and the utilization of personal music systems during physical exertion.

Peripheral hearing loss following head trauma in children.

The purpose of this prospective study was to determine the incidence and type of hearing loss occurring in children who suffered head injuries. Fifty children admitted to the neurosurgical service after sustaining head trauma were studied. Neurologic, otologic, and audiologic evaluations were performed. Diagnostic studies included skull roentgenograms and computerized tomography scans. A 32% incidence of conductive hearing loss and a 16% incidence of high-frequency sensorineural hearing loss was found in this group. All patients with temporal bone fractures had conductive hearing losses, but the presence of a skull vault fracture did not correlate with the presence, type, or degree of hearing loss. In addition, there was no correlation between either cause of injury, loss of consciousness, or Glasgow Coma Scale scores and the presence, type, or degree of hearing loss. There was a significant incidence of both sensorineural and conductive hearing loss in this series of patients, which indicates that close audiologic and otologic follow-up is necessary for all head injury patients.

Surgical and nonsurgical complications associated with cochlear prosthesis implantation.

Relatively few complications have been reported for cochlear implant surgery in spite of a recent report detailing a complication rate of 11.8 percent. This report highlights both the surgical and nonsurgical complications we have encountered that have resulted in either replacement of the implanted prosthesis or compromise of the sound processing strategy employed by the external unit. These complications make a strong argument for the use of preoperative, intraoperative, and postoperative radiologic examinations. Since the complications reported herein have not been attributed to the implant device proper, we feel cochlear implantation remains a safe and effective procedure for those patients who are untreatable by traditional methods.

Magnetically evoked facial nerve potential.

Facial nerve stimulation by electrical current is painful and tends to discourage serial studies. Transcutaneous magnetic stimulation of the facial nerve is painless, easily reproducible, and elicits facial muscle responses identical to electrical stimulation.