Temporal Bone Fracture

Red flags

  • CSF otorrhoea / rhinorrhoea
  • Facial nerve paralysis
  • Post-auricular or periorbital ecchymosis
  • Haemotympanum / pinna haematoma / lacerations
  • Severe nystagmus
  • Vertigo

 

Why is this important?

  • Potential ENT short and long term complications include CSF leak, meningitis, hearing loss, and facial nerve palsy

 

When to involve the ENT Registrar

  • All cases should be discussed with the ENT registrar the next morning or during working hours; patients with facial nerve palsy should be discussed urgently

 

Who to admit

  • All patients with confirmed temporal bone fracture should be admitted under the trauma team for neurological observation and further multidisciplinary assessment/management of the head injury

 

Assessment and recognition

  • A full otoneurological examination is required which includes examination of the cranial nerves
  • Look specifically for Battle’s signs (bruising over the mastoid process), lower motor neurone facial nerve palsy, and CSF otorrhoea or rhinorrhoea, and nystagmus
  • Otoscopy may reveal haemotympanum (bluish colour), tympanic membrane perforation or a step deformity in the bony external auditory canal
  • Tuning fork tests (512 Hz – Weber and Rinne’s) and bedside vestibular function testing
  • Thorough examination of the rest of the head and neck for other injuries (eg mid-facial fractures)
  • A CT scan of the head is crucial; ideally a fine-slice CT of the temporal bones should also be done to image the ear adequately. This will diagnose temporal bone fractures and associated intracranial pathology. It is important to note whether fractures involve the otic capsule or brain parenchyma
  • By reference to the long axis of the petrous temporal bone (ie in the plane of the ear canal), 80% of temporal bone fractures are longitudinal (from lateral blows) and 20% transverse (from fronto-occipital trauma)
  • Longitudinal fractures more commonly cause conductive hearing loss and although 20% injure the facial nerve. Transverse fractures are associated with sensorineural hearing loss and a much higher rate of facial nerve injury. In reality, many fractures will have a mixed pattern

 

Immediate and overnight management

  • Immediate management of a head injury should follow the ATLS protocol
  • Depending on the injuries, a multidisciplinary team may be needed for immediate management including an anaesthetist, ENT surgeon, neurosurgeon, maxillofacial surgeon, and general surgeon
  • Neurosurgical management of intracranial pathologies takes precedence over otological pathology
  • Most otological complications do not require immediate management (see below). The exception is severe bleeding from the external auditory meatus which may represent jugular bulb or carotid artery injury - this is exceedingly rare

 

Further management

CSF LEAK

  • Up to a third of patients will have CSF leak. This resolves with conservative management in the majority of patients. A leak can be confirmed by testing fluid for beta-2 transferrin, which has 100% specificity for CSF. If a leak persists beyond five days, a lumbar drain can facilitate resolution. Failing this, surgical closure can be undertaken. Routine antibiotic use for meningitis prophylaxis is not recommended; there is a similar incidence of meningitis in antibiotic treated and untreated populations.

 

LOWER MOTOR NEURON FACIAL NERVE PALSY

  • Facial nerve palsy is rare (<10% of temporal bone fractures) unless there has been a penetrating injury, in which case the frequency rises. Immediate and complete facial palsy suggests transection of the nerve, whereas a delayed and partial palsy suggests neurapraxia from fracture oedema.
  • There is debate as to whether early surgical exploration and decompression is beneficial. Patients with any complete facial nerve palsy warrant electroneuronography testing. If there is > 95% nerve degeneration within 14 days of injury, these patients may be offered facial nerve decompression. Incomplete facial nerve palsy is managed expectantly with oral steroid.

 

HEARING LOSS

  • Many patients will have a degree of conductive hearing loss, which often resolves spontaneously. An ENT follow up appointment at 6 weeks for audiometric testing is appropriate in patients with hearing loss.
  • Persistent conductive hearing loss two months after an injury may imply ossicular chain disruption (most commonly incus dislocation). Audiometric assessment will show an air-bone gap. These patients may benefit from a tympanoplasty.
  • Conductive hearing loss can also be associated with tympanic membrane perforation. This is initially treated conservatively with water precautions. The vast majority of dry perforations heal spontaneously.
  • Haemotympanum is also associated with conductive hearing loss and generally resolves spontaneously.
  • Sensorineural hearing loss +/- vertigo after a temporal bone fracture implies traumatic audio/vestibular failure. The vertigo generally improves as the brain adapts, but hearing loss is likely to be persistent. If unilateral, hearing loss can be left untreated. If bilateral, a cochlear implant can be considered.

 

VERTIGO

  • Persistent vertigo and tinnitus following head trauma may represent a perilymph fistula which may benefit from a routine follow-up in general ENT clinic (exploratory middle ear surgery may be indicated)

 

 

Page last reviewed: 23 September 2016