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

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.

Bulletproof Temporal Bone: A Case of Self-Inflicted Ballistic Injury

Temporal bone injuries due to gunshot wounds are uncommon but devastating, with a high risk of damage to critical neurovascular structures. The high resistance of the temporal bone, the densest bone in the human body, can sometimes avoid a fatal outcome. However, the complications are in many cases devastating and include hearing loss, facial paralysis, cerebrospinal fluid leakage, intracranial damage, and vascular injuries. Our goal was to report a case of ballistic injury to the temporal bone and describe the surgical approach taken for treatment. A 74-year-old man was transferred to the emergency room of our tertiary hospital, intubated and sedated, after an attempted suicide with a firearm. The CT scan showed the metal projectile lodged within the temporal bone on the right side, with the destruction of the ossicular chain and bony labyrinth. After stabilization, sedation was reversed, and the otolaryngology team was called. On examination, the entry wound was located in the cavum concha, with no active bleeding but presenting active otorrhea of cerebrospinal fluid. The patient had complete peripheral facial paralysis on the right side and spontaneous horizontal nystagmus toward the left side. Empirical antibiotic therapy was initiated. A subtotal petrosectomy was performed, with the removal of the foreign body, repair of the cerebrospinal fluid fistula, obliteration of the cavity with abdominal fat, and closure of the external auditory canal. He was discharged on the 11th-day post-surgery, maintaining complete facial paralysis and right-side anacusis, but was able to walk with assistance. In conclusion, penetrating trauma of the temporal bone is a potentially life-threatening situation, and patients that survive have a guarded prognosis, as it often leads to permanent sequelae even when managed promptly.

Air spaces of the temporal bone: a morphometric analysis with clinical implications

BACKGROUND

The main objective of the present study was to analyse the morphological variations of the air spaces of the temporal bone, that is, the pneumatized and air-filled spaces of the temporal bone cavities.

MATERIALS AND METHODS

A total of 99 sides were analysed. Temporal bone pneumatic spaces (TBPS) were defined as the free spaces inside the cavities of the temporal bone filled with air, excluding the volume of the structures present in the investigated region. Total volumes of TBPS were calculated as the sum of total volumes of mastoid air cells (MAC), tympanic cavity (TC), and external auditory canal (EAC). Analyses were performed considering the general population and the female and male subgroups.

RESULTS

The overall results obtained on Polish population were set as follows: the median total volume of TBPS was demonstrated at 7882.58 mm3 (lower quartile [LQ]: 6200.56 mm3; higher quartile [HQ]: 10393.16 mm3). The median volume of MAC was set at 5813.05 mm3 (LQ: 4224.94 mm3; HQ: 8181.81 mm3). The median of the total volume of the EAC was demonstrated at 1294.36 mm3 (LQ: 1099.68 mm3; HQ: 1627.84 mm3).

CONCLUSIONS

In the present study, the morphometric properties of the temporal bone cavities were analysed. The results showed that the total volume of the MAC was, on average, lower in women than in men. This should be taken into account when performing procedures on the mastoid, such as mastoidectomies. It is hoped that the results of this study can help reduce potential surgical complications associated with otological procedures.

Pintail Comb Injury as a Rare Cause of Penetrating Temporal Bone Trauma With Facial Paralysis

We present a case of novel penetrating temporal bone trauma with a pintail comb causing facial paralysis. We describe a 42-year-old woman with acute facial paralysis, hearing loss, and dizziness following accidental tympanic membrane puncture. The patient underwent middle ear exploration with tympanoplasty and was found to have an intact but severely edematous facial nerve. The patient demonstrated less than 90% degeneration under electroneuronography and was treated medically without decompression, and by 6 months had exhibited complete resolution of facial nerve dysfunction with normal hearing. This case report highlights a unique cause of penetrating temporal bone trauma and supports the utility of electroneuronography in predicting the likelihood of recovery and need for decompression in patients where the facial nerve has obvious signs of trauma but remains grossly intact.