13 temporal bone trauma

Temporal Bone TraumaTemporal Bone Trauma

October 12, 2005October 12, 2005

Steven T. Wright, M.D.Steven T. Wright, M.D.

Matthew Ryan, M.D.Matthew Ryan, M.D.


Wide spectrum of Wide spectrum of clinical findingsclinical findings

Knowledge of the Knowledge of the anatomy is vital to anatomy is vital to proper diagnosis and proper diagnosis and appropriate appropriate managementmanagement

Incidence and EpidemiologyIncidence and Epidemiology

Motorized TransportationMotorized Transportation 30-75% of blunt head trauma had associated 30-75% of blunt head trauma had associated

temporal bone traumatemporal bone trauma

Penetrating TraumaPenetrating Trauma More dismal prognosisMore dismal prognosis

BarotraumaBarotrauma Inner ear decompression sicknessInner ear decompression sickness

• The “bends”The “bends” Perilymphatic fistulaPerilymphatic fistula Blast InjuriesBlast Injuries

Evaluation and ManagementEvaluation and Management

ATLSATLS AirwayAirway BreathingBreathing CirculationCirculation

H & PH & P Thorough head & neck Thorough head & neck

examinationexamination

Physical ExaminationPhysical Examination

Basilar Skull Basilar Skull FracturesFractures Periorbital Ecchymosis Periorbital Ecchymosis

(Raccoon’s Eyes)(Raccoon’s Eyes) Mastoid Ecchymosis Mastoid Ecchymosis

(Battle’s Sign)(Battle’s Sign) HemotympanumHemotympanum

Physical ExaminationPhysical Examination

Tuning Fork examTuning Fork exam Pneumatic OtoscopyPneumatic Otoscopy

Flaccid TMFlaccid TM NystagmusNystagmus

ImagingImaging

HRCTHRCT MRIMRI Angiography/ MRAAngiography/ MRA

Longitudinal fracturesLongitudinal fractures

80% of Temporal 80% of Temporal Bone FracturesBone Fractures

Lateral Forces along Lateral Forces along the petrosquamous the petrosquamous suture linesuture line

15-20% Facial Nerve 15-20% Facial Nerve involvementinvolvement

EAC lacerationEAC laceration

Transverse fracturesTransverse fractures

20% of Temporal 20% of Temporal Bone FracturesBone Fractures

Forces in the Antero-Forces in the Antero-Posterior directionPosterior direction

50% Facial Nerve 50% Facial Nerve InvolvementInvolvement

EAC intactEAC intact


Hearing LossHearing Loss Dizziness/VertigoDizziness/Vertigo CSF OtorrheaCSF Otorrhea Facial Nerve InjuriesFacial Nerve Injuries

Hearing LossHearing Loss

Formal Audiometry Formal Audiometry vs. Tuning Forkvs. Tuning Fork

71% of patients with 71% of patients with Temporal Bone Temporal Bone Trauma have hearing Trauma have hearing lossloss

TM PerforationsTM Perforations CHL > 40db CHL > 40db

suspicious for suspicious for ossicular discontinuityossicular discontinuity


Longitudinal FracturesLongitudinal Fractures Conductive or mixed hearing lossConductive or mixed hearing loss 80% of CHL resolve spontaneously80% of CHL resolve spontaneously

Transverse FracturesTransverse Fractures Sensorineural hearing lossSensorineural hearing loss Less likely to improveLess likely to improve


Tympanic Membrane PerforationsTympanic Membrane Perforations Ossicular fracture or discontinuityOssicular fracture or discontinuity HemotympanumHemotympanum Treatment: Treatment:

ObservationObservation Otic solutions may only mask CSF leaksOtic solutions may only mask CSF leaks

DizzinessDizziness

Fracture through the otic capsule or a Fracture through the otic capsule or a labyrinthine concussionlabyrinthine concussion

Difficult diagnosis- bed rest, obtundation, Difficult diagnosis- bed rest, obtundation, sedationsedation

Treatment: reserved for vomiting, Treatment: reserved for vomiting, limitation of activity limitation of activity Vestibular suppressantsVestibular suppressants Allow for maximal central compensationAllow for maximal central compensation

DizzinessDizziness Perilymphatic FistulasPerilymphatic Fistulas

SCUBA diver with ETDSCUBA diver with ETD Fluctuating dizziness and/or hearing lossFluctuating dizziness and/or hearing loss Tullio’s PhenomenonTullio’s Phenomenon ManagementManagement

• Conservative treatment in first 10-14 daysConservative treatment in first 10-14 days• 40% spontaneously close40% spontaneously close• Surgical management for persistent vertigo or Surgical management for persistent vertigo or

hearing losshearing loss• Regardless of visualization of fistula site, the Regardless of visualization of fistula site, the

majority of patients get bettermajority of patients get better

DizzinessDizziness

Inner Ear Inner Ear Decompression Decompression SicknessSickness Too rapid an ascent Too rapid an ascent

leads to percolation of leads to percolation of nitrogen bubbles within nitrogen bubbles within the otic capsule.the otic capsule.

Greater than 30 ft…. Greater than 30 ft…. Decompression stages Decompression stages upon ascent are upon ascent are neededneeded

DizzinessDizziness

BPPVBPPV Acute, latent, and Acute, latent, and

fatiguable vertigofatiguable vertigo Can occur any time Can occur any time

following injuryfollowing injury Dix HallpikeDix Hallpike Epley ManeuverEpley Maneuver

CSF OtorrheaCSF Otorrhea

AcquiredAcquired Postoperative (58%)Postoperative (58%) Trauma (32%)Trauma (32%) Nontraumatic (11%)Nontraumatic (11%)

SpontaneousSpontaneous Bony defect theoryBony defect theory Arachnoid granulation theoryArachnoid granulation theory

Temporal bone fracturesTemporal bone fractures

LongitudinalLongitudinal 80% of Temp bone fx80% of Temp bone fx Anterior to otic capsuleAnterior to otic capsule Involve the dura of the Involve the dura of the

middle fossamiddle fossa


TransverseTransverse 20% of Temp bone fx20% of Temp bone fx High rate of SNHL due High rate of SNHL due

to violation of the otic to violation of the otic capsulecapsule

50% facial nerve 50% facial nerve involvementinvolvement

Testing of Nasal SecretionsTesting of Nasal Secretions

Beta-2-transferrin is highly sensitive and Beta-2-transferrin is highly sensitive and specificspecific 1/501/50thth of a drop of a drop Gold top tube, may need to send a sample of Gold top tube, may need to send a sample of

the patients serum also.the patients serum also. Found in Vitreous Humor, Perilymph, CSFFound in Vitreous Humor, Perilymph, CSF

Electronic nose has shown early successElectronic nose has shown early success Faster (<24hrs)Faster (<24hrs) Very AccurateVery Accurate

Imaging CSF OtorrheaImaging CSF Otorrhea

High resolution CTHigh resolution CT ConvenienceConvenience SpeedSpeed

CT CisternographyCT Cisternography MRIMRI

Heavily weighted T2Heavily weighted T2 Slow flow MRISlow flow MRI MRI cisternographyMRI cisternography

ImagingImaging

Slow flow MRISlow flow MRI Diffusion weighted Diffusion weighted

MRIMRI Fluid motion down to Fluid motion down to

0.5mm/sec0.5mm/sec Ex. MRA/MRVEx. MRA/MRV

Treatment of CSF OtorrheaTreatment of CSF Otorrhea

Conservative measuresConservative measures Bed rest/Elev HOB>30Bed rest/Elev HOB>30 Stool softenersStool softeners No sneezing/coughingNo sneezing/coughing +/- lumbar drains+/- lumbar drains

Early failuresEarly failures Assoc with hydrocephalusAssoc with hydrocephalus Recurrent or persistent leaksRecurrent or persistent leaks

Treatment of CSF OtorrheaTreatment of CSF Otorrhea

Brodie and Thompson et al.Brodie and Thompson et al. 820 T-bone fractures/122 CSF leaks820 T-bone fractures/122 CSF leaks Spontaneous resolution with conservative Spontaneous resolution with conservative

measuresmeasures 95/122 (78%): within 7 days95/122 (78%): within 7 days 21/122(17%): between 7-14 days21/122(17%): between 7-14 days 5/122(4%): Persisted beyond 2 weeks5/122(4%): Persisted beyond 2 weeks


MeningitisMeningitis 9/121 (7%) developed meningitis. Found no 9/121 (7%) developed meningitis. Found no

significant difference in the rate of meningitis significant difference in the rate of meningitis in the ABX group versus no ABX group.in the ABX group versus no ABX group.

A later meta-analysis by the same author A later meta-analysis by the same author did reveal a statistically significant did reveal a statistically significant reduction in the incidence of meningitis reduction in the incidence of meningitis with the use of prophylactic antibiotics.with the use of prophylactic antibiotics.

Pediatric temporal bone fracturesPediatric temporal bone fractures

Much lower incidence (10:1, adult:pedi)Much lower incidence (10:1, adult:pedi) Undeveloped sinuses, skull flexibilityUndeveloped sinuses, skull flexibility

otorrhea>> rhinorrheaotorrhea>> rhinorrhea Prophylactic antibiotics did not influence Prophylactic antibiotics did not influence

the development of meningitis.the development of meningitis.

CSF Otorrhea Surgical CSF Otorrhea Surgical ManagementManagement

Surgical approachSurgical approach Status of hearing Status of hearing Meningocele/encephaloceleMeningocele/encephalocele Fistula locationFistula location

TransmastoidTransmastoid Middle Cranial FossaMiddle Cranial Fossa

Overlay vs UnderlayOverlay vs Underlaytechniquetechnique

Meta-analysis Meta-analysis showed that both showed that both techniques have techniques have similar success ratessimilar success rates

Onlay: adjacent Onlay: adjacent structures at risk, or if structures at risk, or if the underlay is not the underlay is not possiblepossible

Technique of closureTechnique of closure

Muscle, fascia, fat, cartilage, etc..Muscle, fascia, fat, cartilage, etc.. The success rate is significantly higher for The success rate is significantly higher for

those patients who undergo primary those patients who undergo primary closure with a multi-layer technique versus closure with a multi-layer technique versus those patients who only get single-layer those patients who only get single-layer closure.closure.

Refractory cases may require closure of Refractory cases may require closure of the EAC and obliteration.the EAC and obliteration.

Facial Nerve InjuriesFacial Nerve Injuries

Loss of forehead wrinklesLoss of forehead wrinkles Bell’s PhenomenonBell’s Phenomenon Nasal tip pointing awayNasal tip pointing away Flattened Nasofacial grooveFlattened Nasofacial groove

Facial Nerve AnatomyFacial Nerve Anatomy


Initial Evaluation is the most important Initial Evaluation is the most important prognostic factorprognostic factor Previous statusPrevious status TimeTime Onset and progressionOnset and progression Complete vs. IncompleteComplete vs. Incomplete

House Brackman ScaleHouse Brackman ScaleII NormalNormal Normal facial functionNormal facial function

IIII MildMild Slight synkinesis/weaknessSlight synkinesis/weakness

IIIIII ModerateModerate Complete eye closure, noticeable Complete eye closure, noticeable synkinesis, slight forehead synkinesis, slight forehead movementmovement

IVIV ModeratelModerately Severey Severe

Incomplete eye closure, symmetry Incomplete eye closure, symmetry at rest, no forehead movement, at rest, no forehead movement, dysfiguring synkinesisdysfiguring synkinesis

VV SevereSevere Assymetry at rest, barely Assymetry at rest, barely noticeable motionnoticeable motion

VIVI TotalTotal No movementNo movement

Electrophysiologic TestingElectrophysiologic Testing

NET: Nerve Excitability TestNET: Nerve Excitability Test MST: Maximal Stimulation TestMST: Maximal Stimulation Test ENoG: ElectroneurographyENoG: Electroneurography Goal is to determine whether the lesion is partial Goal is to determine whether the lesion is partial

or complete?or complete? Neuropraxia: Transient block of axoplasmic flow ( no Neuropraxia: Transient block of axoplasmic flow ( no

neural atrophy/damage)neural atrophy/damage) Axonotmesis: damage to nerve axon with Axonotmesis: damage to nerve axon with

preservation of the epineurium (regrowth)preservation of the epineurium (regrowth) Neurotmesis: Complete disruption of the nerve ( no Neurotmesis: Complete disruption of the nerve ( no

chance of organized regrowth)chance of organized regrowth)

Nerve Excitability TestNerve Excitability TestMaximal Stimulation TestMaximal Stimulation Test

Stimulating electrodes are placed and a Stimulating electrodes are placed and a gross movement is recordedgross movement is recorded Not as objective and reliableNot as objective and reliable

>3.5mA difference suggests a poor >3.5mA difference suggests a poor prognosis for return of facial function.prognosis for return of facial function. Correlates with >90% degeneration on ENoGCorrelates with >90% degeneration on ENoG

ElectroneuronographyElectroneuronography

Most accurate, qualitative measurementMost accurate, qualitative measurement Sensing electrodes are placed, a voluntary Sensing electrodes are placed, a voluntary

response is recordedresponse is recorded Accurate after 3 daysAccurate after 3 days Requires an intact side to compare toRequires an intact side to compare to Reduction of >90% amplitude correlates Reduction of >90% amplitude correlates

with a poor prognosis for spontaneous with a poor prognosis for spontaneous recoveryrecovery

ElectromyographyElectromyography

Electrode is placed within the muscle and Electrode is placed within the muscle and voluntary movement is attempted.voluntary movement is attempted.

Normal Muscle is electrically silent. Normal Muscle is electrically silent. After 10-14 days, the denervated muscle After 10-14 days, the denervated muscle

begins to spontaneously fire:begins to spontaneously fire: Diphasic/Polyphasic potentials: GoodDiphasic/Polyphasic potentials: Good Loss of voluntary potentials: BadLoss of voluntary potentials: Bad

Facial Nerve InjuriesFacial Nerve InjuriesWHO GETS TREATMENT?WHO GETS TREATMENT?

Conservative treatment candidatesConservative treatment candidates Surgical treatment candidatesSurgical treatment candidates


Chang & CassChang & Cass Medline search back to 1966Medline search back to 1966 Individually reviewed each articleIndividually reviewed each article 1) Understand the pathophysiology of facial 1) Understand the pathophysiology of facial

nerve damage in temporal bone trauma.nerve damage in temporal bone trauma. 2) What is the effect of surgical intervention 2) What is the effect of surgical intervention

on the ultimate outcome of the facial nerve.on the ultimate outcome of the facial nerve. 3) Propose a rational course for evaluation 3) Propose a rational course for evaluation

and treatment.and treatment.

Facial Nerve InjuriesFacial Nerve InjuriesChang & CassChang & Cass

Pathophysiology based on findings by Fisch and Pathophysiology based on findings by Fisch and Lambert and Brackmann:Lambert and Brackmann:

Where?Where? Perigeniculate, Labyrinthine, and meatal segmentsPerigeniculate, Labyrinthine, and meatal segments Concern over findings of endoneural fibrosis and neural atrophy Concern over findings of endoneural fibrosis and neural atrophy

proximal to the lesionsproximal to the lesions In an untreated human specimen found intraneural edema and In an untreated human specimen found intraneural edema and

demyelinization that extended proximally to the meatal foramendemyelinization that extended proximally to the meatal foramen How?How?

Longitudinal FracturesLongitudinal Fractures• 15% transection15% transection• 33% bony impingement, 43% hematoma33% bony impingement, 43% hematoma

Transverse FracturesTransverse Fractures• 92% transection92% transection

Does Facial Nerve decompression result in Does Facial Nerve decompression result in superior functional outcomes compared with superior functional outcomes compared with

no treatment?no treatment? Not enough human data!Not enough human data! Boyle-monkey: prophylactic epineural decompression in Boyle-monkey: prophylactic epineural decompression in

complete paralysis did not improve recovery of facial complete paralysis did not improve recovery of facial nerve function after induced complete paralysisnerve function after induced complete paralysis

Kartush: Prophylactic decompression of the meatal Kartush: Prophylactic decompression of the meatal segment during acoustic neuroma decreased the segment during acoustic neuroma decreased the incidence of delayed paralysisincidence of delayed paralysis

Adour: compared patients with complete paralysis found:Adour: compared patients with complete paralysis found: Equal outcome with observation vs. decompression without Equal outcome with observation vs. decompression without

nerve slittingnerve slitting Worse outcome with decompression with nerve slittingWorse outcome with decompression with nerve slitting

Does Facial Nerve decompression result in Does Facial Nerve decompression result in superior functional outcomes compared with superior functional outcomes compared with

no treatment?no treatment? Many difficulties in Study designs, Many difficulties in Study designs,

controls, etc, but they made some rough controls, etc, but they made some rough estimates:estimates: 50% of patients who undergo facial nerve 50% of patients who undergo facial nerve

decompression obtain excellent outcomesdecompression obtain excellent outcomes The true efficacy of facial nerve The true efficacy of facial nerve

decompression surgery for trauma decompression surgery for trauma remains uncertainremains uncertain

Conservative Treatment Conservative Treatment CandidatesCandidates

Chang and CassChang and Cass Present with Present with Normal Facial FunctionNormal Facial Function

regardless of progressionregardless of progression Incomplete paralysis and no Incomplete paralysis and no

progressionprogression to complete paralysis to complete paralysis

Less than Less than 95%95% degeneration by ENoG degeneration by ENoG• Most data comes from Bell’s palsy/tumor studies Most data comes from Bell’s palsy/tumor studies

by Fisch.by Fisch.

Conservative Treatment Conservative Treatment CandidatesCandidates

Brodie and ThompsonBrodie and Thompson All patients that presented with normal facial All patients that presented with normal facial

nerve function initially that progressed to nerve function initially that progressed to

complete paralysiscomplete paralysis recovered to a recovered to a HB HB 1 or 2.1 or 2.

Surgical CandidatesSurgical Candidates

Critical Prognostic factorsCritical Prognostic factors ImmediateImmediate vs. Delayed vs. Delayed CompleteComplete vs. Incomplete paralysis vs. Incomplete paralysis ENoG criteriaENoG criteria

Algorithm for Facial Nerve InjuryAlgorithm for Facial Nerve Injury

Facial Nerve InjuriesFacial Nerve InjuriesChang & CassChang & Cass

What time frame is best to operate?What time frame is best to operate? Fisch-cats: Decompression of the nerve within Fisch-cats: Decompression of the nerve within

a 12 day period resulted in “excellent” a 12 day period resulted in “excellent” functional recovery. Presumption was that it functional recovery. Presumption was that it preserved endoneural tubules. (limits the preserved endoneural tubules. (limits the damage to axonotmesis at worst)damage to axonotmesis at worst)

Limits the accuracy of your patient selection Limits the accuracy of your patient selection because EMG is not reliable until day 10-14.because EMG is not reliable until day 10-14.

Surgical ApproachSurgical Approach

Medial to the Geniculate GanglionMedial to the Geniculate Ganglion No useful hearingNo useful hearing

• Transmastoid-translabyrinthineTransmastoid-translabyrinthine Intact hearingIntact hearing

• Transmastoid-trans-epitympanicTransmastoid-trans-epitympanic• Middle Cranial FossaMiddle Cranial Fossa

Lateral to Geniculate GanglionLateral to Geniculate Ganglion TransmastoidTransmastoid

Surgical ApproachSurgical Approach

Chang & CassChang & Cass Histopathologic studyHistopathologic study Severe facial nerve Severe facial nerve

injury results in injury results in retrograde axonal retrograde axonal degeneration to the level degeneration to the level of the labyrinthine and of the labyrinthine and probably meatal probably meatal segmentssegments

Surgical findings of Surgical findings of greater than greater than 50%50% nerve transection/damage nerve transection/damage

Nerve repair via primary anastamosis or Nerve repair via primary anastamosis or cable graft repaircable graft repair HB 1 or 2: 0%HB 1 or 2: 0% HB 3 or 4: 82%HB 3 or 4: 82% HB 5 or 6: 18%HB 5 or 6: 18%

Iatrogenic Facial Nerve InjuriesIatrogenic Facial Nerve Injuries

Mastoidectomy (55%)Mastoidectomy (55%) Tympanoplasty (14%)Tympanoplasty (14%) Bony Exostoses (14%)Bony Exostoses (14%) Lower tympanic segment is the most Lower tympanic segment is the most

common location injurycommon location injury 79% were not identified at the time of 79% were not identified at the time of

surgerysurgery

Management of Iatrogenic Management of Iatrogenic Facial Nerve InjuriesFacial Nerve Injuries

Green, et al.Green, et al. <50% damage: perform decompression<50% damage: perform decompression

75% had HB of 3 or better!75% had HB of 3 or better! >50% damage: perform nerve repair>50% damage: perform nerve repair

No patients had better than a HB 3No patients had better than a HB 3 Beware of local anestheticsBeware of local anesthetics General consensus: acute, complete, General consensus: acute, complete,

postoperative paralysis should be explored postoperative paralysis should be explored as soon as possible.as soon as possible.

EmergenciesEmergencies

Brain HerniationBrain Herniation Massive HemorrhageMassive Hemorrhage

Pack the EACPack the EAC Carotid arteriography with embolizationCarotid arteriography with embolization

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Journal of Otology; 18: 188-197, 1997.Journal of Otology; 18: 188-197, 1997. Brodie HA, Prophylactic Antibiotic for Posttraumatic CSF Fistulas. Arch of Otolaryngology- Head and Neck Brodie HA, Prophylactic Antibiotic for Posttraumatic CSF Fistulas. Arch of Otolaryngology- Head and Neck

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Otology; 3: 254-261, 1992.Otology; 3: 254-261, 1992. Chang CY, Cass SP. Management of Facial Nerve Injury Due to Temporal Bone Trauma. The American Journal Chang CY, Cass SP. Management of Facial Nerve Injury Due to Temporal Bone Trauma. The American Journal

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Health & Medicine

13 temporal bone trauma