w5

Question 1

types of temporal bone traumas

Answer 1

• blunt trauma (strike to head)
• penetrating (injury penetrates skull ex., gunshot wound)
• compressive (slow skull compression)
• Barotrauma (scuba diving)

Question 2

how do ontario trauma centers work

Answer 2

identified by specialized equipment and staff
– “Level” designation: Level I (highest) to Level III (lowest)

Question 3

Medical: Neuro-otologic exam for temporal bone trauma

Answer 3

Subjective: assess patient for disequilibrium, hearing loss, vertigo or prior otologic history
Mechanism of injury: direction of force site of inpact
Cranial nerve assessment (any trauma?)
Tuning forks (crude assessment of hearing)
Radiology: CT high resolution

Question 4

Structures at risk from temporal bone fracture

Answer 4

cranial nerve, cochlea, ossicles, TM, carotid artery, jugular vein

Question 5

physical examination of TB fracture

Answer 5

External ear: lacerations, hematoma (bruise), bony deformity, battle sign-bruising around temporal bone
Fractures can be open to middle ear or cranium: is the CSF leaking out of ear, eustachian tube, otorrhea- clear (CSF), blood (issue elsewhere)
Periorbital hematoma (raccoon eyes)

Question 6

TB fracture Audiology:

Answer 6

standard audiometric assessment, otoscopy to determine status of OAM & TM,
Immittance: variety depending on pathology (reduced with fluid in ME, hypermobile with ossicular disarticulation)

Question 7

TB fracture sex

Answer 7

Sex: 3 male: 1 female

Question 8

TB fracture age

Answer 8

3rd and 4th decade

Question 9

TB fracture imaging

Answer 9

• Imaging follows acute stabilization of life-threatening injuries
• Screening head CT to rule out intracranial injuries
• High-resolution CT scan of temporal bones if fracture suspected

Question 10

indications for high resolution CT of temporal bones

Answer 10

– facial paralysis
– Cerebral spinal fluid leak
– disruption of superior wall of EAC
– vascular injury

Question 11

Classification of temporal bone fractures:

Answer 11

Traditional: longitudinal, transveres, mixed (complex)
Newer classification: sparing of optic capsule (Bony labyrinth surrounding cochlea), disruption of otic capsule

Question 12

Longitudinal fracture

Answer 12

(otic capsule sparing)
Structures Involved: EAC, TM, ME, ossicles, Facial Nerve

Question 13

Longitudinal fracture presentation

Answer 13

conductive component (tympanic disruption, ossicular derangement, hemorrhage into ME), FN paresis

Question 14

traumatic force can also

Answer 14

injure oval window
» produce forceful fluid wave with mechanical damage to hair cells
» causes a piston-like movement of the stapes which can penetrate inner ear & damage structures

Question 15

– Hemotympanum

Answer 15

• Serial monitoring
• Often resolves spontaneously (≈ 1 month)

Question 16

– TM perforation

Answer 16

• Serial monitoring
• Often resolves spontaneously (≈ 3 months)
  – Tympanoplasty if not

Question 17

longitudinal fracture medical management

Answer 17

80% CHL resolves spontaneously
Ossicular damage suggested by residual CHL following resolution of hemotympanum
Exploratory tympanotomy
- 30dB CHL persisting > 2m after injury
- contraindications: CHL in only hearing ear

Question 18

common ossicular injuries

Answer 18

• Incudostapedial joint
• dislocation of incus
• Fracture of stapes crura

Question 19

Ossiculoplasty

Answer 19

Surgical repair of disarticulation. stapes intact- rate of hearing recovery is about 75% stapes not intact - the rate of hearing recovery is about 50%

Question 20

Transverse temporal bone Fracture
Structures involved:

Answer 20

otic capsule, IAC, FN

Question 21

Transverse temporal bone Fracture presentation

Answer 21

sensorineural HL, vestibular dysfunction , FN paresis
* Perpendicular to long axis of temporal bone
* Impact often at frontal or occipital area
* Usually involves otic capsule with SNHL & vestibular symptoms
* Less common: middle ear involvement (with conductive component)

Question 22

audiological management

Answer 22

Varies with outcome
Monitoring: spontaneous recovery; pre & post intervention
With temporary or permanent residual hearing loss:
– Amplification
– Assistive devices
– Cochlear implantation
– Aural rehabilitation (including vocational depending on severity/nature of residual activity and participation limitations)

Question 23

prognosis of SNHL for TB fractures

Answer 23

• Prognosis
  – Profound SNHL has poor prognosis
  – Moderate SNHL may have some recovery