Temporal Bone Trauma

RebeccaSCornelius,MD,FACRProfessorofRadiology&Otolaryngology

UniversityofCincinnatiCollegeofMedicine

Goals & Objectives • Classifytemporalbonefracturesusingthetraditionalandoticcapsuleclassificationmethods

• Identifyclassificationmethodwhichbestpredictspatientoutcomes

• Recognizethemostcommoncomplicationsassociatedwithtemporalbonefracture

Parts of Temporal Bone Fracture Classification • Traditional-categorizedinregardtopositionofthefracturerelativetopetrousridge

• Newerfractureclassificationcategorizesfracturesrelativetoinvolvementoftheoticcapsule

Traditional Classification • Basedonexperimentalfracturesproducedincadavers

• Similartoclinicallyobservedfractures

• Anatomicfracturelocationusedinanattempttopredictclinicalsequelae

Clinical sequelae • CHL• SNHL• VIInerveparalysis• CSFleak/meningitis• Vertigo• Vascular–carotiddissection,pseudoaneurysm,sigmoidsinusthrombosis

• Acquiredcholesteatoma

Why does it matter? • Importanceoffractureclassificationistotrytopredictclinicalsequelaeandclinicaloutcome

• Morerecentstudiessuggestthatthetraditionalclassificationsystemfailstoreliablypredictanycomplication

How do I report T-bone fractures? Ireportbothclassifications:E.G.“Thereisalongitudinalpetroustemporalbonefracturewhichtraversesthemiddleearcavitybutsparestheoticcapsulestructures.”• Traditionalclassificationgivesabetter“visualpicture”offracture

• Oticcapsuleclassificationsystembetterpredictspatientmorbidity

Fracture Classification-Traditional • Longitudinal=Paralleltolongaxisofpetroustemporalbone

• Transverse=Perpendiculartolongaxisofpetroustemporalbone

• Intruthmostfracturesarecomplexwithasomewhatserpiginouscourse

• In1992,arevisedclassificationsystemincludedanobliquefracture

New Classification • Oticcapsulesparingvs• Oticcapsuleviolating

• Severalstudiessupportbetterpredictiveabilityforseriousclinicaloutcomeusingnewclassificationsystem

Little & Kessler 2006 Univ Virginia, Charlottesville Little&Kessler2006UnivVirginia,Charlottesville

Little&Kessler2006UnivVirginia,Charlottesville Little&Kessler2006UnivVirginia,Charlottesville

Pts with otic capsule violating fx • 5xmorelikelytohavefacialnerveinjury

• 25xmorelikelytohaveSNHL

• 8xmorelikelytohaveCSFleak

Review of Traditional Classification Longitudinal Transverse

Longitudinal Fracture • Mostcommon,duetotemporoparietaltrauma• CommonlyassociatedsquamousT-bonefx• UsuinvolvestheTM,EACwhemotympanum• Ofteninvolvesossicles• MayinvolveCNVII• Mayextendtocarotidcanal

Longitudinal fracture- otic capsule sparing

Conductive Hearing Loss • Hemotympanum• TMdamage• Ossicularderangement• AnteriorEACfxandsubsequentstenosis

Longitudinal fracture with hemotympanum

EAC fracture requiring canalplasty EAC fractures • Directtraumacanresultinalocalizedfractureofthemastoidand/orEAC

• IndirecttraumaviaablowtothemandiblecanresultinananteriorwallEACfx

Ossicular Derangement 1.  Incudostapedialjointsubluxation2.  Completeincusdislocation3.  Fractureofstapesarch•  Fractureofmalleus•  Isolatedmalleoincudalsubluxation

Mayalsobenoiseinducedorsecondarytobarotrauma

Malleoincudal subluxation

Fracture with ossicular dislocation

Longitudinal fracture with incus dislocation

Longitudinal fracture with incudostapedial dislocation

Transverse Fracture • Lesscommon,duetofrontaloroccipitalimpact• OssiclesandTMusuallyspared• HigherincidenceofVIIparalysis**oftenimmediateandcomplete• Labyrinthineinvolvementcommon• CantransectIAC• MayhaveacutecompleteSNHL&vertigo

SNHL • FractureIAC(TransectionofCNVIII)• Fractureinvolvingcochlea• Labyrinthineconcussion

Vertigo • FractureIAC(TransectionCNVIII)• Transectionofvestibuleorvestibularaqueduct

• Labyrinthineconcussion• Perilymphfistula

Facial Nerve Paralysis •  Resultsfrom:*Transection*Intraneuronalhematoma*Impingement/ischemia

Transverse otic capsule sparing fracture Transverse otic capsule violating fracture

Perilymph fistula • Disruptionofovalorroundwindow

• Pneumolabyrinth• Persistentvertigoandfluctuatingsensorineuralhearingloss

Longitudinal fracture with pneumolabyrinth

Air in TMJ associated with T-bone fracture CSF Leak • Resultsfromdisruptionoftegmenanddura

• CSFotorrheaifTMdisrupted• CSFrhinorrheaifTMintact• Canresultinmeningitis

Complex fracture with tegmen disruption Fracture with tegmen involvement and CSF leak

Vascular Sequelae

Lambdoid diastasis, longitudinal fracture, epidural hematoma & venous thrombosis

Longitudinal fracture with sigmoid/IJ thrombosis Squamous T-bone fx, skull base fx, ICH and occlusive cervical ICA dissection

T-bone fx, sphenoid fx, ICA dissection Acquired Cholesteatoma • Occursinlongitudinalormixedfracture• SecondarytoinvasionofsquamousepithelialdebrisintoEACormiddleearalongfractureline

• Canbeveryaggressive

EAC Cholesteatoma

CourtesyofRaviSamy,MD

Thanks for your attention!