Audiologic Consequences of Gunshot Wounds to the Temporal Bone Show No Relation to Concomitant Neurologic or Vascular Injuries

Abstract

Objectives: To evaluate audiologic consequences of gunshot wounds (GSWs) to the temporal bone (TB), and to correlate hearing outcomes with neurologic and vascular injuries adjacent to the temporal bone. Study design: Retrospective case series. Setting: University-based level-one trauma center. Methods: Retrospective review of 35 patients surviving TB ballistic injury, 2012 to 2021. Main outcomes were audiologic results. Demographics, concomitant injuries, CT, and interventions were reviewed. Results: Mean age was 30.7 years; 80% male. Seventeen patients (48.6%) underwent audiologic testing. Mean pure tone average (PTA) was 75 ± 35 dB, bone line average 41 ± 26 dB, and speech discrimination score (SDS) 60 ± 43%. Nineteen (54.3%) demonstrated facial nerve injury (FNI), who were more likely to show SNHL especially anacusis, though their mean PTA and SDS were not statistically different from those without ( P = .30 and .47, respectively). Radiographic review of those with sensorineural loss (SNHL, 6/17) revealed otic capsule-disrupting fracture (n = 2), pneumolabyrinth (n = 2), intracranial hemorrhage (n = 3). Those with mixed loss (6/17) showed otic capsule-sparing fracture (n = 6), EAC injury (n = 5), ossicular discontinuity (n = 2), and intracranial hemorrhage (n = 4). Two with mastoid tip fractures alone had normal audiograms. Audiometric outcomes were not predicted by concomitant CSF leak, spinal injuries, vascular injuries, cranial neuropathies, or traumatic brain injury. Conclusions: All patterns of hearing loss—conductive, sensorineural, mixed and normal—may be seen following TB ballistic injuries. Trauma severe enough to disrupt the facial nerve is more likely to cause anacusis. However, all should be formally evaluated, since ballistic injuries complicated by neurologic or vascular damage do not necessarily correlate with worse audiologic outcomes, while patients with minimal fractures may demonstrate losses.