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Diagnosis and Diagnosis and Imaging of TBIImaging of TBI

James G. Smirniotopoulos, M.D.James G. Smirniotopoulos, M.D.Center for Neuroscience and Regenerative MedicineCenter for Neuroscience and Regenerative Medicine

Professor of Radiology, Neurology, and Biomedical InformaticsProfessor of Radiology, Neurology, and Biomedical InformaticsChair, Department of RadiologyChair, Department of Radiology

Uniformed Services UniversityUniformed Services UniversityBethesda, MDBethesda, MD

Traumatic Brain InjuryTraumatic Brain InjuryClinically heterogeneous populationClinically heterogeneous populationEtiology and Pathophysiology DiverseEtiology and Pathophysiology Diverse–– Closed InjuryClosed Injury

ConcussiveConcussiveBlast waveBlast wave

–– Penetrating InjuryPenetrating Injury

PathoanatomicPathoanatomic Assessment is ComplexAssessment is ComplexTemporal Evolution of LesionsTemporal Evolution of Lesions–– Changes over timeChanges over time

Epidemiology of TBIEpidemiology of TBIDuring 2002, the Centers for Disease During 2002, the Centers for Disease Control and Prevention (CDC) estimated Control and Prevention (CDC) estimated that more than that more than 50,000 Americans die 50,000 Americans die each year from traumatic brain injury each year from traumatic brain injury (TBI)(TBI) –– approximately oneapproximately one--third from third from motor vehicle accidents, 10% from falls, motor vehicle accidents, 10% from falls, and and 40% [20k] from penetrating wounds 40% [20k] from penetrating wounds caused by firearmscaused by firearms..

Adekoya N, Thurman DJ, White DD, Webb KW. Surveillance for Traumatic Brain Injury Deaths --- United States, 1989--1998.Morbidity and Mortality Weekly Report 51[SS10], 1-16. 2007.

Classification of TBIClassification of TBININDS NINDS ““Classification of TBI for Targeted TherapiesClassification of TBI for Targeted Therapies”” –– Oct 2007Oct 2007

Clinical (intake) Criteria Clinical (intake) Criteria –– GCS or ??GCS or ??PathoanatomicPathoanatomic ClassificationClassification–– Imaging and PathologyImaging and Pathology

Physical MechanismPhysical Mechanism–– Impact, Acceleration/DecelerationImpact, Acceleration/Deceleration–– Overpressure (Primary Blast Injury)Overpressure (Primary Blast Injury)

PathophysiologyPathophysiology–– Primary DamagePrimary Damage–– Secondary Insult (Secondary Insult (↓↓BP, BP, ↓↓ O2, O2, ↑↑pCO2, pCO2, ↑↑BP)BP)

Prognostic ModelingPrognostic Modeling

Problems with GCSProblems with GCSGCS 3 GCS 3 –– comatose to GCS 15 comatose to GCS 15 –– awakeawakeNOT a good predictor of cognitive NOT a good predictor of cognitive sequelaesequelae>80% of >80% of mTBImTBI or Concussion have or Concussion have GCS 13GCS 13--1515GCS is a poor discriminator GCS is a poor discriminator ≥≥1313GCS is a poor discriminator GCS is a poor discriminator ≤≤44

Six Patients w/ GCS < 6Six Patients w/ GCS < 6

Vasospasm

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PathoanatomicPathoanatomic TBITBI

Contusion

Diffuse Axonal Injury

SAH

Hematoma

Ball Bearing from IEDBall Bearing from IED

Ball Bearing from IEDBall Bearing from IED

Scalp hematoma, skull fracture, cortical contusion, surface fragment

IED: Penetrating InjuryIED: Penetrating Injury

Intracranial air, blood and metal fragments along wound track.

IED Penetrating Injury IED Penetrating Injury –– Brain SwellingBrain Swelling IED Penetrating Injury IED Penetrating Injury –– Brain SwellingBrain Swelling

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What is Blast TBI (What is Blast TBI (bTBIbTBI)?)?LOC, PTA, GCS probably NOT useful in LOC, PTA, GCS probably NOT useful in bTBIbTBIUnknown how they relate to Unknown how they relate to bTBIbTBIMost of these Most of these bTBIbTBI have associated have associated CxCxspine injuries.spine injuries.

Blast Related Axonal InjuryBlast Related Axonal Injury

Frontal WM Tracks Cerebellar WM Tracks

Case, after Case, after CaseCase, after Case, after CaseNormally, that would be a series Normally, that would be a series ……Often, it literally means three casesOften, it literally means three casesIn consideration of Primary Blast InjuryIn consideration of Primary Blast Injury–– It is the same case being shown by everyone, It is the same case being shown by everyone,

and shown everywhereand shown everywhere

Blast as Signature InjuryBlast as Signature Injury

Primary Blast

TBI Complications

• Hypotension

• Hypoxia

• Hemodilution

• Vasospasm

• Hyperemia

• Potentiation

TherapyBlast “Plus”

•Impact 2°

•Concussion 3°

UnderdiagnosisUnderdiagnosis of Blast TBIof Blast TBICivilian blast Civilian blast underdiagnosedunderdiagnosedCausesCauses–– Private dwelling(31), Industrial pressure(20), Private dwelling(31), Industrial pressure(20),

Industrial gas(16), Military Training(15), Industrial gas(16), Military Training(15), Home explosive(8), Fireworks(1)Home explosive(8), Fireworks(1)

Types of Types of bTBIbTBI–– Cerebral Contusion(13), SDH(8), DAI(4), Cerebral Contusion(13), SDH(8), DAI(4),

SAH(3),ICH(3),EDH(3),IVH(2)SAH(3),ICH(3),EDH(3),IVH(2)

Robust Imaging PortfolioRobust Imaging PortfolioCT CT -- Computed TomographyComputed TomographyMRI MRI –– Magnetic Resonance ImagingMagnetic Resonance Imaging–– DTI and DTI and TractographyTractography–– MRS MRS –– fMRIfMRI –– attention, memory, PTSDattention, memory, PTSD

NM NM -- Nuclear MedicineNuclear Medicine–– FDG PETFDG PET–– SPECT, New labeling agentsSPECT, New labeling agents

PathologyPathology–– Gross brain examinationGross brain examination–– HistologyHistology

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Five Easy PiecesFive Easy PiecesWho Needs Imaging?Who Needs Imaging?Skull, Scalp, and EpiduralSkull, Scalp, and Epidural–– Lucid Interval, Drain or notLucid Interval, Drain or not

SubduralSubdural–– Variable PresentationVariable Presentation–– Variable AppearanceVariable Appearance

ContusionContusion–– Coup vs. Coup vs. ContrecoupContrecoup

Shearing InjuryShearing Injury–– Deep LesionsDeep Lesions–– ComaComa

Traumatic Brain InjuryTraumatic Brain InjuryMotor deficitsMotor deficitsSeizureSeizureSensory deficitSensory deficitCoordinationCoordinationMemoryMemoryPersonalityPersonalityExecutive functioningExecutive functioning

Executive FunctionsExecutive FunctionsDefine a GoalDefine a GoalMake a PlanMake a PlanMeasure progress toward the GoalMeasure progress toward the GoalExampleExample–– Renew your driverRenew your driver’’s licenses license–– Bring flowers for MotherBring flowers for Mother’’s Days Day

Clinical Diagnosis of Head TraumaClinical Diagnosis of Head Trauma

Rising Blood PressureSlowing PulseSlowing RespirationsComa– Unconscious– UnresponsiveFundoscopic Examination – Dilated Pupil(s)– EOM’s ?

Cushing’s Triad

CNS TRAUMACNS TRAUMAImpactImpact–– CONTACT INJURYCONTACT INJURY–– Scalp/skull AbnormalScalp/skull Abnormal

InertialInertial–– NONNON--CONTACT INJURYCONTACT INJURY–– Acceleration/decelerationAcceleration/deceleration–– Scalp/skull NormalScalp/skull Normal

Types of InjuryTypes of InjuryPrimary Brain LesionsPrimary Brain Lesions–– Immediate Neurological EffectsImmediate Neurological Effects–– ContusionsContusions–– Shearing InjuryShearing Injury

Secondary Brain LesionsSecondary Brain Lesions–– Variable Delay in Symptoms and SignsVariable Delay in Symptoms and Signs–– Epidural, Subdural, Subarachnoid HemorrhageEpidural, Subdural, Subarachnoid Hemorrhage–– Mass Effect, Increased ICP, Brain HerniationMass Effect, Increased ICP, Brain Herniation–– Vasospasm, Hyperemic Swelling, Brain InfarctionVasospasm, Hyperemic Swelling, Brain Infarction

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Causes of Head TraumaCauses of Head TraumaMotor Vehicle AccidentsMotor Vehicle Accidents–– 50%50%Falls from a heightFalls from a height–– 20%20%AccidentalAccidentalNonNon--accidental (e.g. Child Abuse)accidental (e.g. Child Abuse)WorkplaceWorkplaceRecreationalRecreationalCombatCombat

TBI Educational ObjectivesTBI Educational ObjectivesWho needs brain imaging?Who needs brain imaging?What type of imaging is needed?What type of imaging is needed?Intraaxial Lesions Intraaxial Lesions »» Primary LesionsPrimary Lesions–– Contusion, Shearing InjuryContusion, Shearing Injury–– Immediate Neurological EffectsImmediate Neurological Effects

Extraaxial Lesions Extraaxial Lesions »» Secondary LesionsSecondary Lesions–– Epidural, Subdural, SubarachnoidEpidural, Subdural, Subarachnoid–– Delayed Neurological EffectsDelayed Neurological Effects

Indications for ImagingIndications for ImagingAcute Neurologic Deficit Acute Neurologic Deficit Observed L. O. C.Observed L. O. C.Persistent HA Persistent HA Severe Trauma Severe Trauma Obvious InjuryObvious Injury

Hydroplaning AccidentHydroplaning Accident9 passenger van9 passenger vanAll belted inAll belted in180 direction turn180 direction turn22--1/2 turn barrel rollover1/2 turn barrel rolloverNo one blacked outNo one blacked outEveryone walked awayEveryone walked awayShould we have been scanned?Should we have been scanned?

Minor Head Trauma:Minor Head Trauma:with Normal GCSwith Normal GCS

““CT can be safely limited to CT can be safely limited to those who have those who have …”…”–– HeadacheHeadache–– SeizuresSeizures–– VomitingVomiting–– Age > 60 yrsAge > 60 yrs–– Drug or Drug or EtOHEtOH intoxicationintoxication–– Physical trauma above claviclesPhysical trauma above clavicles

NEJM 2000;34: 100-1005

DxDx Sensitivity/SpecificitySensitivity/SpecificitymTBImTBI or Concussion may not be imagedor Concussion may not be imagedMost patients have only screening CTMost patients have only screening CT–– 85% 85% ““NormalNormal”” -- Insensitive test for Insensitive test for mTBImTBI

““Mild TBI or concussion with a normal GCS Mild TBI or concussion with a normal GCS …… CT CT …… lesions in less than 15% lesions in less than 15% …”…”–– NeurorehabilNeurorehabil Neural Repair 2008; 22: 217Neural Repair 2008; 22: 217--

227.227.

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Minor Head Trauma:Minor Head Trauma:with Normal GCSwith Normal GCS

““CT can be safely limited to CT can be safely limited to those who have those who have …”…”–– HeadacheHeadache–– SeizuresSeizures–– VomitingVomiting–– Age > 60 yrsAge > 60 yrs–– Drug or Drug or EtOHEtOH intoxicationintoxication–– Physical trauma above claviclesPhysical trauma above clavicles

NEJM 2000;34: 100-1005

We would like to add:

Post-traumatic amnesia > 30min

Anosmia

Ruptured Tympanic Membrane

Roller Coaster HeadacheRoller Coaster Headache

Roller Coasters can create 2.5 Roller Coasters can create 2.5 –– 3.5 G3.5 G’’ssGrandpa rides with Grandpa rides with GrandaughterGrandaughter–– SheShe’’s screaming with excitements screaming with excitement–– HeHe’’s subdued by a Subdural Hematomas subdued by a Subdural Hematoma

Reference:Reference:FukutakeFukutake T, Mine S, T, Mine S, YamakamiYamakami I, I, YamauraYamaura A, Hattori T. A, Hattori T. Roller coaster headache and subdural hematoma. Roller coaster headache and subdural hematoma. Neurology. 2000 Jan 11;54(1):264. Neurology. 2000 Jan 11;54(1):264. PMID: 10636168; UI: 20100123 PMID: 10636168; UI: 20100123

TBI Educational ObjectivesTBI Educational ObjectivesWho needs brain imaging?Who needs brain imaging?What type of imaging is needed?What type of imaging is needed?Intraaxial Lesions Intraaxial Lesions »» Primary LesionsPrimary Lesions–– Contusion, Shearing InjuryContusion, Shearing Injury–– Immediate Neurological EffectsImmediate Neurological Effects

Extraaxial Lesions Extraaxial Lesions »» Secondary LesionsSecondary Lesions–– Epidural, Subdural, SubarachnoidEpidural, Subdural, Subarachnoid–– Delayed Neurological EffectsDelayed Neurological Effects

Traumatic Brain InjuryTraumatic Brain InjuryNINDS NINDS ““Classification of TBI for Targeted TherapiesClassification of TBI for Targeted Therapies”” –– Oct 2007Oct 2007

Clinical (intake) Criteria Clinical (intake) Criteria –– GCS or ??GCS or ??PathoanatomicPathoanatomic ClassificationClassification–– Imaging and PathologyImaging and PathologyPhysical MechanismPhysical Mechanism–– Impact, Acceleration/DecelerationImpact, Acceleration/Deceleration–– Overpressure (Primary Blast Injury)Overpressure (Primary Blast Injury)

PathophysiologyPathophysiology–– Primary DamagePrimary Damage–– Secondary Insult (Secondary Insult (↓↓BP, BP, ↓↓ O2, O2, ↑↑pCO2, pCO2, ↑↑BP)BP)

Prognostic ModelingPrognostic Modeling

History of Imaging TBIHistory of Imaging TBIAutopsyAutopsySkull series plain filmsSkull series plain filmsAngiographyAngiography–– Gross mass lesions (EDH, SDH)Gross mass lesions (EDH, SDH)

Computed TomographyComputed Tomography–– EDH, SDH, Contusion, some DAIEDH, SDH, Contusion, some DAI

Conventional Spin Echo MRIConventional Spin Echo MRI–– More of the aboveMore of the above

GRE/MSI, DTI, MRS, GRE/MSI, DTI, MRS, fMRIfMRI–– Even moreEven more

1970s Pre1970s Pre--CTCTClinical EvaluationClinical Evaluation–– Clinical Examination of CNN 2Clinical Examination of CNN 2--1212–– Pupils evaluated for signs of herniationPupils evaluated for signs of herniation

Skull XSkull X--ray Seriesray SeriesAngiographyAngiography““Exploratory Burr HolesExploratory Burr Holes””

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Little bit of history Little bit of history ……

10 mm of pineal shift – subfalcial herniationCourtesy of Alice B. Smith and UCSF

Obvious InjuryObvious Injury

1980s1980sAll Level 1 Trauma Centers must have All Level 1 Trauma Centers must have 25X7 CT available25X7 CT availableHow do you triage patients?How do you triage patients?Who gets Who gets ““advancedadvanced”” neuroimagingneuroimaging??–– Obvious InjuriesObvious Injuries

Times Have ChangedTimes Have ChangedIn 1980 CT replaced Skull SeriesIn 1980 CT replaced Skull SeriesIn 2000 MRI complemented CTIn 2000 MRI complemented CT–– But did not replace CT as screening examBut did not replace CT as screening exam

In 2008? In 2008? ……–– MRI w/ DWI, GRE/SWI, DTI, MRSMRI w/ DWI, GRE/SWI, DTI, MRS–– fMRIfMRI w/ New paradigmsw/ New paradigms–– PET/SPECT, Biomarker ImagingPET/SPECT, Biomarker Imaging

Imaging of Head TraumaImaging of Head TraumaAutopsyAutopsyPlain RadiographsPlain RadiographsAngiographyAngiographyComputed TomographyComputed TomographySpin Echo MRISpin Echo MRIFLAIR, DWI, ADC mapsFLAIR, DWI, ADC mapsSusceptibility Imaging Susceptibility Imaging -- SWISWIDiffusion Tensor Imaging Diffusion Tensor Imaging -- DTIDTI

Newest

Oldest

Relative SensitivityRelative SensitivityMR Spectroscopy (global decreased NAA)MR Spectroscopy (global decreased NAA)Diffusion Tensor Imaging Diffusion Tensor Imaging –– (anisotropy)(anisotropy)Magnetic Susceptibility (SWI or GRE)Magnetic Susceptibility (SWI or GRE)Apparent Diffusion CoefficientApparent Diffusion CoefficientDiffusion Weighted ImagingDiffusion Weighted ImagingFLAIRFLAIRConventional SE MR (T2W > T1W)Conventional SE MR (T2W > T1W)

CT (ECT > NCT)CT (ECT > NCT)Skull RadiogramSkull Radiogram

Lower

Higher

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3 Reasons for Getting an MR3 Reasons for Getting an MR

CT fails to explain PtCT fails to explain Pt’’s Conditions Condition

CT fails to explain PtCT fails to explain Pt’’s Conditions Condition

CT fails to explain PtCT fails to explain Pt’’s Conditions Condition

Hospitalized patients need further evaluation with MR

Imaging of Head TraumaImaging of Head TraumaAutopsyAutopsyPlain RadiographsPlain RadiographsAngiographyAngiographyComputed TomographyComputed TomographySpin Echo MRISpin Echo MRIFLAIR, DWI, ADC mapsFLAIR, DWI, ADC mapsSusceptibility Imaging Susceptibility Imaging -- SWISWIDiffusion Tensor Imaging Diffusion Tensor Imaging -- DTIDTI

Thanks to Dr. Pam Schaefer, MGH

T2

DWI

SWI

Thanks to Dr. Pam Schaefer, MGH

MRI Techniques VaryMRI Techniques Vary HistoryHistory26 26 y/oy/o man transferred by airman transferred by air--evacevac after a after a helicopter crash. Upon arrival, patient was helicopter crash. Upon arrival, patient was intubatedintubated and sedated. CT of the head and sedated. CT of the head was performed as part of trauma was performed as part of trauma evaluation.evaluation.

26 26 y.oy.o. man in Coma. man in Coma Causes of ComaCauses of ComaPhysiologic/metabolic conditions:Physiologic/metabolic conditions:–– HypoxiaHypoxia–– HypotensionHypotension–– HypoglycemiaHypoglycemia–– Drugs and IntoxicantsDrugs and Intoxicants

Structural/anatomic lesions:Structural/anatomic lesions:–– Cerebral HemispheresCerebral Hemispheres–– ThalamusThalamus–– Reticular Activating System (brainstem)Reticular Activating System (brainstem)

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Causes of ComaCauses of Coma

ExpressiveCortex

AssociativeCortex

Receptive Cortex

Internal Reference Cortex

Thalamus

Reticular Activating

System

ArousalResponsiveness

Coma: Lesions and LocationsComa: Lesions and Locations

Subcortical Subcortical –– many neededmany neededWhite Matter White Matter –– many neededmany neededThalamus Thalamus –– few neededfew neededReticular Activating SystemReticular Activating System–– Dorsal BrainstemDorsal Brainstem–– Only one neededOnly one needed

Shearing Lesions are small (<15mm) and deep (subcortical, WM, Corpus callosum, Thalamus, Brain stem

26 26 y.oy.o. man in Coma. man in Coma

CT Scan MR Scan w/”blood sensitive” technique

Deep Lesions … including thalamus … “shearing injury”

… causing coma

FindingsFindingsNo Midline shiftNo Midline shiftNo explanation for GCS of 6No explanation for GCS of 6Possible Possible small hemorrhagesmall hemorrhage left occipital left occipital hornhorn–– Torn subependymal veins?Torn subependymal veins?–– Shearing Injury?Shearing Injury?

MR with a MR with a ““blood sensitiveblood sensitive”” sequencesequence–– Left occipital horn bloodLeft occipital horn blood–– Right thalamic bleedRight thalamic bleed–– Central corpus callosum bleedCentral corpus callosum bleed

Differential DiagnosisDifferential DiagnosisShearing InjuryShearing InjuryDiffuse Axonal InjuryDiffuse Axonal InjuryDiffuse White Matter InjuryDiffuse White Matter Injury

Traumatic HemorrhageTraumatic HemorrhageSubgalealSubgalealCephalohematomaCephalohematoma–– Subperiosteal Outer TableSubperiosteal Outer Table

Epidural (Extradural) Epidural (Extradural) –– Subperiosteal Inner TableSubperiosteal Inner Table

Subdural Subdural –– ‘‘EpiEpi--arachnoidarachnoid’’

SubarachnoidSubarachnoidParenchymal HemorrhageParenchymal HemorrhageIntraIntra--ventricularventricular

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TBI Educational ObjectivesTBI Educational ObjectivesWho needs brain imaging?Who needs brain imaging?What type of imaging is needed?What type of imaging is needed?Extraaxial Lesions Extraaxial Lesions »» Secondary LesionsSecondary Lesions–– Epidural, Subdural, SubarachnoidEpidural, Subdural, Subarachnoid–– Delayed Neurological EffectsDelayed Neurological Effects

Intraaxial Lesions Intraaxial Lesions »» Primary LesionsPrimary Lesions–– Contusion, Shearing InjuryContusion, Shearing Injury–– Immediate Neurological EffectsImmediate Neurological Effects

CENTRIPETAL APPROACHCENTRIPETAL APPROACH(outside to inside)(outside to inside)

––ScalpScalp––CalvariumCalvarium––EpiduralEpidural––SubduralSubdural––SubarachnoidSubarachnoid––IntraIntra--parenchymalparenchymal––IntraIntra--ventricularventricular

CNS TRAUMA CNS TRAUMA ---- SUBGALEALSUBGALEALBetween periosteum of OUTER table and Between periosteum of OUTER table and the GALEA (under scalp fat)the GALEA (under scalp fat)In CHILD, significant blood lossIn CHILD, significant blood lossSpontaneous decompression of Spontaneous decompression of intracranial (Epidural) hematomaintracranial (Epidural) hematoma

Subgaleal HematomaSubgaleal Hematoma

CENTRIPETAL APPROACHCENTRIPETAL APPROACH(outside to inside)(outside to inside)

––ScalpScalp––CalvariumCalvarium––EpiduralEpidural––SubduralSubdural––SubarachnoidSubarachnoid––IntraIntra--parenchymalparenchymal––IntraIntra--ventricularventricular

Skull FracturesSkull FracturesLinear Linear Stellate Stellate Depressed Depressed Basilar Basilar EggshellEggshell

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Linear Skull FxLinear Skull Fx

Density indicates overlapping bone – depressed skull fracture

Depressed Skull FxDepressed Skull Fx

Basilar Skull FractureBasilar Skull FractureRHINORRHEA (CSF) RHINORRHEA (CSF) OTORRHEA (CSF / OTORRHEA (CSF / HemotympanumHemotympanum) ) PNEUMOCEPHALUS PNEUMOCEPHALUS –– air in sulciair in sulci–– air and fluid/levels in sinuses air and fluid/levels in sinuses RACCOON EYESRACCOON EYES–– periorbitalperiorbital ecchymosesecchymosesBATTLE'S SIGNBATTLE'S SIGN–– RetroRetro--auricular ecchymosesauricular ecchymoses

BASILAR SKULL Fx:BASILAR SKULL Fx:CSF LEAKCSF LEAK–– InfectionInfection–– PneumocephalusPneumocephalusCNN. INJURYCNN. INJURY–– Deficit Acute or DelayedDeficit Acute or DelayedVASCULAR TRAUMA VASCULAR TRAUMA –– Laceration or dissection Laceration or dissection –– Occlusion & infarction Occlusion & infarction –– FISTULAE (CarotidFISTULAE (Carotid--Cavernous)Cavernous)

Traumatic Hemorrhage:Traumatic Hemorrhage:SubgalealSubgalealSubperiosteal Outer TableSubperiosteal Outer Table–– CephalohematomaCephalohematoma

Subperiosteal Inner TableSubperiosteal Inner Table–– Epi (Extra) DuralEpi (Extra) Dural

Subdural Subdural –– ‘‘EpiEpi--arachnoidarachnoid’’

Subarachnoid ***Subarachnoid ***Parenchymal HemorrhageParenchymal HemorrhageIntraIntra--ventricularventricular

Membrane Hematomas:Membrane Hematomas:

CephalohematomaCephalohematoma–– SubSub--periostealperiosteal, Outer Table , Outer Table

SkullSkullEpidural hematomaEpidural hematoma–– SubSub--periostealperiosteal, Inner Table , Inner Table

SkullSkullSubdural hematomaSubdural hematoma–– EpiEpi--arachnoidarachnoid

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Epidural SpaceEpidural Space

•Scalp & Skull

•Dura & Arachnoid

•Pia and Brain

•Ventricle and CSF

2 y.o. with dilated pupil2 y.o. with dilated pupil

Midline Herniation: Subfalcial and Downward Transtentorial

CNS TRAUMA EPIDURAL CNS TRAUMA EPIDURAL HEMATOMAHEMATOMA

Young Men (20Young Men (20--40's)40's)–– Head Trauma frequentHead Trauma frequent–– Also, dura (periosteum) more adherent in Also, dura (periosteum) more adherent in

older peopleolder people

Acute presentationAcute presentationSkull fracture (90%)Skull fracture (90%)BiBi--convex, hyperdenseconvex, hyperdense-- limited by sutureslimited by sutures

EPIDURAL HEMATOMAEPIDURAL HEMATOMASource of BleedingSource of Bleeding

MENINGEAL VESSELSMENINGEAL VESSELSArterial (high pressure)Arterial (high pressure)Venous (low pressure)Venous (low pressure)

DURAL SINUSDURAL SINUSHigh flow, low pressureHigh flow, low pressure

OTHEROTHERDiploic veins (Fx)Diploic veins (Fx)Marrow sinusoidsMarrow sinusoids

EPIDURAL HEMATOMAEPIDURAL HEMATOMASignificant traumaSignificant traumaFracture & concussion (l.o.c.)Fracture & concussion (l.o.c.)

Lucid IntervalLucid Interval––pt Wakes Uppt Wakes Up––40% pts.40% pts.Delayed neurologic Sx (hrs. Later)Delayed neurologic Sx (hrs. Later)Herniation, coma and deathHerniation, coma and death

EPIDURAL HEMATOMAEPIDURAL HEMATOMATrauma Trauma --> fracture & concussion> fracture & concussionTearing/stripping of both layers Tearing/stripping of both layers

from inner tablefrom inner tableLaceration of outer periosteal Laceration of outer periosteal

layerlayerLaceration of meningeal vesselsLaceration of meningeal vesselsInner (meningeal dura) intactInner (meningeal dura) intactBlood between naked bone and Blood between naked bone and

duraduraNORMAL arterial pressure NORMAL arterial pressure

continues to dissect continues to dissect periosteumperiosteum from bonefrom bone

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Epidural HematomaEpidural Hematoma

Fx Fx

t t

f

Brain Herniation SyndromesBrain Herniation Syndromes Epidural HematomaEpidural Hematoma

Epidural Hematoma Epidural Hematoma -- TreatmentTreatment

•Craniotomy

•Drain clot

•Repair the Artery!

Small EDH Small EDH –– Conservative TxConservative Tx

☺

Smile of the Quadrigeminal Cistern

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Progressive EDHProgressive EDH

8 PM10 AM

SUBPERIOSTEAL HEMATOMASUBPERIOSTEAL HEMATOMA–– CEPHALOHEMATOMACEPHALOHEMATOMA

–– (Birth trauma)(Birth trauma)–– (outer table, sub(outer table, sub--periosteal)periosteal)

–– EPIDURAL HEMATOMAEPIDURAL HEMATOMA–– (Inner table, "sub(Inner table, "sub--periosteal")periosteal")

CephalohematomaCephalohematomaBirth TraumaBirth Trauma Cephalohematoma Cephalohematoma -- CalcifiedCalcified

Membrane HematomaMembrane HematomaEpiduralEpidural–– AcuteAcute–– BiconvexBiconvex–– UnilateralUnilateral–– Skull fractureSkull fracture–– Limited by suturesLimited by sutures

SubduralSubdural–– Acute to ChronicAcute to Chronic–– Concave layerConcave layer–– BilateralBilateral–– Fracture +/Fracture +/--–– Cross suturesCross sutures

Traumatic Hemorrhage:Traumatic Hemorrhage:SubgalealSubgalealCephalohematomaCephalohematoma–– Subperiosteal Outer TableSubperiosteal Outer Table

Epidural (Extradural) Epidural (Extradural) –– Subperiosteal Inner TableSubperiosteal Inner Table

Subdural Subdural –– ‘‘EpiEpi--arachnoidarachnoid’’

SubarachnoidSubarachnoidParenchymal HemorrhageParenchymal HemorrhageIntraIntra--ventricularventricular

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Subdural HematomaSubdural Hematoma

•Scalp & Skull

•Dura

•Arachnoid

•Pia and Brain

•Ventricle and CSF

Complex Subdural Hematoma:Complex Subdural Hematoma:AdultAdult

1cm pineal shift, 3cm Right-to-Left shift and SubfalcialHerniation

Herniation: Herniation: SubfalcialSubfalcial and and TranstentorialTranstentorial

Left to Right Shift … Subfalcial herniation … Downward Transtentorial

SUBDURAL HEMATOMASUBDURAL HEMATOMAExtremes of ageExtremes of age

Infants/elderlyInfants/elderly

Subacute presentationSubacute presentationDays or weeks after traumaDays or weeks after trauma

Fracture not neededFracture not neededCrescenticCrescentic

Not hyperdenseNot hyperdenseCrosses sutures commonlyCrosses sutures commonlyInterhemispheric fissure (kids)Interhemispheric fissure (kids)

Epi Epi -- ArachnoidArachnoid

SUBDURAL HEMATOMA SUBDURAL HEMATOMA --Source of BloodSource of Blood

Laceration Of Cortical Laceration Of Cortical AaAa. and Vv.. and Vv.Direct: Penetrating InjuryDirect: Penetrating Injury

Large ContusionsLarge ContusionsDirect/indirect: "Pulped Brain"Direct/indirect: "Pulped Brain"

Torn Bridging (Cortical) VeinsTorn Bridging (Cortical) VeinsIndirectIndirectAccelerationAcceleration--decelerationdeceleration

SUBDURAL HEMATOMASUBDURAL HEMATOMA

AccelerationAcceleration--decelerationdecelerationSagittal PlaneSagittal Plane–– Causes Oscillation Of BrainCauses Oscillation Of Brain–– Brain LAGS Behind SkullBrain LAGS Behind Skull

Bridging Veins Stretch & TearBridging Veins Stretch & TearVenous Bleeding (Slow)Venous Bleeding (Slow)Multiple and Bilateral VeinsMultiple and Bilateral Veins

Dissection Of Subdural SpaceDissection Of Subdural Space–– Under Dura => Over ArachnoidUnder Dura => Over Arachnoid–– Spreads around convexitySpreads around convexity–– Into the interhemispheric fissure (child)Into the interhemispheric fissure (child)

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Bridging VeinsBridging Veins

Dural Baffles: Falx and TentoriumDural Baffles: Falx and Tentorium

C

MU

T T

t t

f

SDH SDH »» Brain HerniationBrain Herniation

BS

SDH SDH »» Brain HerniationBrain Herniation PCA Infarct Tentorial HerniationPCA Infarct Tentorial Herniation

Courtesy Mauricio Castillo, M.D. UNC

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Acute Subdural Hematoma:Acute Subdural Hematoma:Child, High AttenuationChild, High Attenuation

Subdural Hematoma StagesSubdural Hematoma Stages

Acute Subacute Chronic< 3 days 3d – 2 wks > 2 wks

Normal Brain Density

⇑

⇓

Hyperdense

Isodense to Brain

Hypodense

Complex Subdural HematomaComplex Subdural Hematoma

Mixed SubacuteMixed Subacute--acuteacuteSubdural HematomaSubdural Hematoma

Acute bloodAcute blood--brightbrightAlternating bandsAlternating bands–– rebleedingrebleeding

Mass effectMass effect–– Subfalcial herniationSubfalcial herniation–– ““TrappedTrapped”” ventricleventricle

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Child Abuse?Child Abuse? Child AbuseChild AbuseThe The ““Multiple SclerosisMultiple Sclerosis”” of trauma:of trauma:–– Lesions separated in spaceLesions separated in space–– Lesions separated in timeLesions separated in time

Ophthalmoscope Exam RequiredOphthalmoscope Exam Required–– Retinal hemorrhage highly correlated with Retinal hemorrhage highly correlated with

nonnon--accidental traumaaccidental trauma

Skeletal survey? Skeletal survey?

Arachnoid MembraneArachnoid Membrane SUBDURAL HEMATOMASUBDURAL HEMATOMASource of ReSource of Re--bleedingbleeding

NEONEO--MEMBRANESMEMBRANES–– fragile capillariesfragile capillaries

BRIDGING VEINSBRIDGING VEINS–– stretching across SDH stretching across SDH –– constant tensionconstant tension

SUBDURAL HEMATOMASUBDURAL HEMATOMA22--3 wks. to develop fully3 wks. to develop fullydevelop from outer (dural) margin develop from outer (dural) margin not from arachnoid sidenot from arachnoid side–– inner (arachnoid) border intactinner (arachnoid) border intact

fibroblasts, and new immature capillaries fibroblasts, and new immature capillaries that are fragilethat are fragile

Membrane HematomaMembrane HematomaEpiduralEpidural–– AcuteAcute–– BiconvexBiconvex–– UnilateralUnilateral–– Skull fractureSkull fracture–– Limited by suturesLimited by sutures

SubduralSubdural–– Acute to ChronicAcute to Chronic–– Concave layerConcave layer–– BilateralBilateral–– Fracture +/Fracture +/--–– Cross suturesCross sutures

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TBI Educational ObjectivesTBI Educational ObjectivesWho needs brain imaging?Who needs brain imaging?What type of imaging is needed?What type of imaging is needed?Extraaxial Lesions Extraaxial Lesions »» Secondary LesionsSecondary Lesions–– Epidural, Subdural, SubarachnoidEpidural, Subdural, Subarachnoid–– Delayed Neurological EffectsDelayed Neurological Effects

Intraaxial Lesions Intraaxial Lesions »» Primary LesionsPrimary Lesions–– Contusion, Shearing InjuryContusion, Shearing Injury–– Immediate Neurological EffectsImmediate Neurological Effects

CEREBRAL CONTUSIONCEREBRAL CONTUSIONTraumatic/mechanical disruption of small Traumatic/mechanical disruption of small (capillary) vessels(capillary) vesselsExtravasation of whole blood, plasma Extravasation of whole blood, plasma (edema) and RBC's(edema) and RBC'sAdmixture of blood mixed with native Admixture of blood mixed with native tissue (petechial hemorrhage)tissue (petechial hemorrhage)Mottled / speckled density ("salt and Mottled / speckled density ("salt and pepper" on CT)pepper" on CT)

CEREBRAL CONTUSIONCEREBRAL CONTUSION

MECHANICAL INJURY TO VESSELSMECHANICAL INJURY TO VESSELSExtravasation of whole bloodExtravasation of whole blood

PETECHIAL / PERIVASCULAR HEMORRHAGEPETECHIAL / PERIVASCULAR HEMORRHAGEAdmixture of tissue and bloodAdmixture of tissue and bloodaverage density may NOT be highaverage density may NOT be high

SWELLING/MASS EFFECTSWELLING/MASS EFFECTMAY PROGRESS TO HEMATOMAMAY PROGRESS TO HEMATOMA

If larger vessels are damagedIf larger vessels are damagedlarge confluent mass of bloodlarge confluent mass of blood

Courtesy of Alice B. Smith, UCSF

Massive ContusionsMassive Contusions

CEREBRAL CONTUSIONCEREBRAL CONTUSIONnaming conventionsnaming conventions

COUPCOUP–– SAME SIDE AS IMPACTSAME SIDE AS IMPACT–– w/fractures, small area of impactw/fractures, small area of impact

INTERMEDIATE (CENTRAL)INTERMEDIATE (CENTRAL)–– DAI/Shearing InjuryDAI/Shearing Injury

CONTRE CONTRE -- COUPCOUP–– OPPOSITE IMPACTOPPOSITE IMPACT–– w/falls, broad surface of impactw/falls, broad surface of impact

Coup vs. ContrecoupCoup vs. Contrecoup

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Coup vs. ContrecoupCoup vs. Contrecoup ContreContre--Coup ContusionCoup Contusion

ContusionContusion ContusionContusion

ContusionContusion

Cranial nerves 2-12 intact … but the patient smells badly, not bad, but badly … Anosmia

ContusionContusion

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••Crowns of GyriCrowns of Gyri

••Linear or flame shapeLinear or flame shape

••NOT in depths of SulciNOT in depths of Sulci

Cerebral Cortical ContusionCerebral Cortical Contusion Cerebral Fx ContusionCerebral Fx Contusion

Acute vs. Chronic ContusionAcute vs. Chronic Contusion TBI Educational ObjectivesTBI Educational ObjectivesWho needs brain imaging?Who needs brain imaging?What type of imaging is needed?What type of imaging is needed?Extraaxial Lesions Extraaxial Lesions »» Secondary LesionsSecondary Lesions–– Epidural, Subdural, SubarachnoidEpidural, Subdural, Subarachnoid–– Delayed Neurological EffectsDelayed Neurological Effects

Intraaxial Lesions Intraaxial Lesions »» Primary LesionsPrimary Lesions–– Contusion, Contusion, Shearing InjuryShearing Injury–– Immediate Neurological EffectsImmediate Neurological Effects

SHEARING INJURIESSHEARING INJURIESDeep lesionsDeep lesionsHigh Velocity (MVA) TraumaHigh Velocity (MVA) TraumaAcceleration/DecelerationAcceleration/Deceleration–– Especially Especially CORONAL angular momentumCORONAL angular momentum–– Side Impact (Running a Red Light)Side Impact (Running a Red Light)

Do not require an impact or Fx.Do not require an impact or Fx.““SHEARING OF AXONSSHEARING OF AXONS””–– Breaks connectionsBreaks connections–– Actual force may be tension & Actual force may be tension & excitoexcito--toxicitytoxicity

““SHEARINGSHEARING”” of Small WM VESSELSof Small WM VESSELSSmall (petechial) hemorrhagesSmall (petechial) hemorrhages

Coronal Angular AccelerationCoronal Angular AccelerationSubcorticalSubcortical –– many neededmany neededWhite Matter White Matter –– many neededmany neededThalamus Thalamus –– few neededfew neededReticular Activating SystemReticular Activating System–– Dorsal BrainstemDorsal Brainstem–– Only one neededOnly one needed

Shearing Lesions are small (<15mm) and deep (subcortical, WM, Corpus callosum, Thalamus, Brain stem

Coma: Lesions and LocationsComa: Lesions and Locations

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Deep Lesions Deep Lesions -- TerminologyTerminology

Intermediate ContusionsIntermediate ContusionsShearing InjuryShearing InjuryDiffuse WhiteDiffuse White--matter Injury (DWI)matter Injury (DWI)Diffuse Axonal Injury (DAI)Diffuse Axonal Injury (DAI)

5 MPH for Pedestrian5 MPH for Pedestrian--AutoAutoAuto weighs 2500 Auto weighs 2500 –– 4000 lbs4000 lbsOne auto hits another autoOne auto hits another auto–– Significant acceleration at 35 mphSignificant acceleration at 35 mph

Auto hits a Pedestrian (60Auto hits a Pedestrian (60--260 lbs)260 lbs)–– Significant acceleration at 5 mphSignificant acceleration at 5 mph

DWI/DAI = Deep LesionsDWI/DAI = Deep Lesions<15mm diameter<15mm diameter and and BELOWBELOW cortexcortexSubcortical and Hemispheric WMSubcortical and Hemispheric WMCorpus CallosumCorpus Callosum–– posterior bodyposterior body–– spleniumspleniumBrain stemBrain stem–– Dorsolateral Quadrant of Upper BSDorsolateral Quadrant of Upper BS–– Deep BSDeep BS–– Ventral BSVentral BS

DIFFUSE AXONAL INJURYDIFFUSE AXONAL INJURY–– Neurologic Sx Begin at ImpactNeurologic Sx Begin at Impact–– Some have Immediate L.O.C.Some have Immediate L.O.C.–– Some have Persistent Vegetative StateSome have Persistent Vegetative State–– Pathology:Pathology:

–– foci of hemorrhage in callosum, brainstem, etc.foci of hemorrhage in callosum, brainstem, etc.–– axon retraction balls (ARB)axon retraction balls (ARB)

–– LongLong--Term Survivors:Term Survivors:–– microglial clustersmicroglial clusters–– foci of demyelinationfoci of demyelination

Deep Lesions Deep Lesions –– Coronal ForcesCoronal Forces

Angular momentum in the Coronal Plane:

Running a Red Light … T-Bone the cars

WM WM –– Axonal Axonal TransectionTransection

Axon Retraction Balls – Cytoplasm leaking from transected axons and disrupted axolemma.

DTI - Diffusion Tensor Imaging:Detects loss of anisotropy in areas where axons are disrupted and disconnected.

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DAI or DWIDAI or DWINon limited to White MatterNon limited to White Matter–– Basal Ganglia and ThalamusBasal Ganglia and Thalamus

Some patients in Some patients in ““ComaComa””–– Different types of Different types of ““ComaComa””

Global lesionsGlobal lesionsSmall focal lesions (e.g. Reticular formation)Small focal lesions (e.g. Reticular formation)

Some patients have only subtle changes Some patients have only subtle changes on specialized psychometric testson specialized psychometric tests

Mouse – no

Rat – no

Cat – no

Monkey – no

Chimpanzee – no

Great Ape – yes

Politician - no

Experimental Model:Experimental Model:Requires Hemisphere >> BrainstemRequires Hemisphere >> Brainstem

University of Wisconsin and Michigan State Comparative Mammalian Brain Collections

Dorsolateral BrainstemDorsolateral Brainstem Corpus CallosumCorpus Callosum

Dense, compact, white matter, bundles of axons

Corpus Callosum Corpus Callosum --> Ventricle> Ventricle Corpus Callosum and BGCorpus Callosum and BG

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LetLet’’s Catchs Catch--up with our Pt up with our Pt ……26 26 y/oy/o man transferred by airman transferred by air--evacevac after a after a helicopter crash. Upon arrival, patient was helicopter crash. Upon arrival, patient was intubatedintubated and sedated. CT of the head and sedated. CT of the head was performed as part of trauma was performed as part of trauma evaluation.evaluation.

26 26 y.oy.o. man in Coma. man in Coma

CT Scan MR Scan w/”blood sensitive” technique

Deep Lesions … including thalamus … “shearing injury”

… causing coma

Corpus CallosumCorpus Callosum

T2W SWI

Deep Lesions … including thalamus … “shearing injury”

… causing coma

Diffuse Axonal Injury Diffuse Axonal Injury -- SWISWI

Thanks to Pam Schaefer

MSIDWI ADCFLAIR

Diffuse WhiteDiffuse White--Matter InjuryMatter Injury

Thanks to Pam Schaefer, MGH

Shearing Injury vs. ContusionShearing Injury vs. Contusion

Contusions are surface lesions