Traumatic Hearing Loss in the Context of Blast-Related Tympanic Membrane Perforation

Abstract

Objectives:

Identify associated clinical factors and characterize the various forms of hearing loss in the context of blast related traumatic tympanic membrane perforation sustained in the combat setting.

Methods:

A prospective study of 41 patients who sustained a perforation secondary to blast injury between 2010-12 while serving in combat. Clinical exams and audiograms were obtained for all patients by a single institution ear, nose, and throat (ENT) service with comparative data generated from review of pre- and post-trauma hearing screens. Follow-up clinical and audiogram data were obtained on all available subjects.

Results:

Fifty-nine tympanic membrane (TM) perforations were documented with audiograms. A conductive hearing loss of 14.8dB, 22.4dB, 20.3dB, and 18.9dB and sensorineural hearing loss of 18.0dB, 13.5dB, 19.9dB, and 22.0dB at 500, 1000, 3000, and 4000 Hz respectively was observed. Forty-nine percent of all hearing loss was SNHL. Clinical factors did not correlate to hearing loss (P > 0.05). Follow-up data were available in 33 patients at an average of 11.8 months. Eighty-eight percent of patients still had tinnitus, and 11% had continued vertigo. Forty-nine percent of perforations healed spontaneously, and 42% had surgical correction. On average, patients demonstrated a 51% improvement in SNHL at time of follow-up.

Conclusions:

In the subacute setting, patients with traumatic TM perforations secondary to combat blast injury demonstrate conductive and sensorineural hearing loss, with 49% of all loss being sensorineural. An average sensorineural hearing loss improvement of 51% was seen at follow-up. Clinical factors did not correlate with hearing loss. 49% of perforations healed spontaneously, and 42% were surgically corrected.