Temporal Bone Fractures

Timothy C. Hain, MD

Most recent update: July 5, 2020 : This page is not written for or intended for use in legal endeavors.

Longitudinal temporal bone fracture Oblique temporal bone fracture

Severe dizziness after the injury, with a temporal bone CT scan showing a fracture. This is often accompanied by hearing loss or peripheral facial weakness ( Bell's Palsy). Temporal bone fractures, especially the oblique variety (see above), may impair hearing and cause dizziness. There often is blood seen behind the ear-drum (hemotympanum). Either a conductive or sensorineural hearing loss or both may be present. Conductive hearing loss may be related to fluid in the middle ear or due to dislocation of the bones (ossicles) in the inner ear.

Fistulae between the inner ear and surrounding spaces can occur in T-bone fracture.  In this instance, air may be seen within the labyrinth on CT ("pneumolabyrinth). This is exceedingly rare.

Fluid may also be seen within the mastoid sinus. It is rare that there is a preexisting MRI or CT scan that can clearly related fluid to temporal proximity.

Vestibular deficits are also common, especially in the oblique variety. Bilateral vestibular problems are exceedingly rare. Causes of fracture, gender, and symptoms are similar in adults and children (Kang et al, 2013).

Diagnosis of temporal bone fracture.

Diagnosis of temporal bone fracture is generally through a CT scan that shows the fracture itself as well as blood in the mastoid sinus. Often there is a less detailed CT scan done acutely followed by a more detailed "temporal bone CT scan" done later. An advantage of the temporal bone CT scan is that ossciular bone damage can be seen, but when the middle ear is full of blood, it is usually best to wait for the blood to clear first. On the other hand, because emergency departments often have their own CT scanners, they may just go ahead and do a temporal bone CT scan right away (perhaps based on seeing blood behind the ear drum).

Rarely air is seen in the labyrinth (pneuomlabyrinth) -- according to Choi et al, only 7% of those with otic capsule fractures (e.g. Oblique above) have air in the labyrinth. When there is air in the cochlea, there eventually is total hearing loss (Choi et al, 2016). We have seen a case in which we suspected that pneuomolabyrinth caused a positional nystagmus. This is very logical considering the biomechanics.

Temporal bone fractures are also a source of BPPV because otoconia can be dislodged due to the same trauma that cracks the temporal bone.

The temporal bone is a very hard bone and it is difficult to break. Because of this, it is common to have brain injuries as well such as concussion, and various types of intracranial bleeds.

Treatment of temporal bone fractures

Treatment, at least initially, of what is generally a closed head injury, usually is conservative. Prophylactic antibiotics are given, usually for 4 weeks. Myringotomy and insertion of a ventilation tube may be indicated, especially for serious otititis that persists after one month (Pulek and Deguine, 2001).

After several months has passed allowing for recovery, residual hearing deficits may be addressed with hearing aids (if the ear is aidable). Because there is a high prevalence of middle ear (ossicular) damage, sometimes there is also an opportunity to restore hearing through middle ear surgery similar to that done for otosclerosis, but with more of an emphasis on attaching the bones rather than freeing up the bones. For example, the ossicles can be cemented back together, which is called an ossiculoplasty (Kalcioglu et al, 2020).

 


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