Mechanical InjuriesMechanical Injuries

Of Of

Brain and MenigesBrain and Meniges

11๐๐ Traumatic Traumatic LesionsLesions

22๐๐ AlterationsAlterations

11๐๐ Traumatic LesionsTraumatic Lesions

Extracerebral lesionsExtracerebral lesions

Intracerebral lesionsIntracerebral lesions

11๐๐ Traumatic LesionsTraumatic Lesions

Close injuryClose injury

Open injuryOpen injury

Extracerebral LesionsExtracerebral Lesions

Epidural bleedingEpidural bleeding

Subdural bleedingSubdural bleeding

Subaracnoid bleedingSubaracnoid bleeding

IntraventricularIntraventricular bleeding bleeding

Intracerebral LesionsIntracerebral Lesions

ContusionsContusions

Lacerations Lacerations ((or Woundsor Wounds))

22๐๐ AlterationsAlterations

Circulatory disorderCirculatory disorder

Necroses and hemorrhagesNecroses and hemorrhages

Post-traumatic hydrocephalusPost-traumatic hydrocephalus

Secondary infectionsSecondary infections

Fat and air embolismFat and air embolism

EpiduralEpidural

BleedingBleeding

Epidural BleedingEpidural Bleeding

Epidural / ExtraduralEpidural / Extradural

Hemorrhage / HematomaHemorrhage / Hematoma

CausesCauses

Skull fractureSkull fracture

Separation of dura and skull boneSeparation of dura and skull bone

Tear of a dural artery ,its branches Tear of a dural artery ,its branches and/or occasionally of a veinand/or occasionally of a vein

Most common site: lateral convexity Most common site: lateral convexity of a cerebral hemisphereof a cerebral hemisphere

Location: it almost always at the site Location: it almost always at the site of a skull fracture of a skull fracture

Uncommon occur in the elderlyUncommon occur in the elderly

Children: skull deformation with Children: skull deformation with separation of the dura from the bone separation of the dura from the bone without skull fracture without skull fracture

Acute hematoma: artery bleedingAcute hematoma: artery bleeding

Delayed hematoma: venous bleeding, Delayed hematoma: venous bleeding, transient arterial spasmtransient arterial spasm

Progression of the bleedingProgression of the bleeding

Space occupying hematomaSpace occupying hematoma

Increase intracranial pressureIncrease intracranial pressure

Confusion Confusion

Alteration of consciousnessAlteration of consciousness

Pupillary dilatation: Pupillary dilatation: on the hematoma sideon the hematoma side

Central respiratory failureCentral respiratory failure

If venous bleeding ,or transient If venous bleeding ,or transient arterial spasm: Lucid intervalarterial spasm: Lucid interval

ConsciousnessConsciousness ( (may bemay be)) ,no signs of ,no signs of confusion: occipital poles and/or confusion: occipital poles and/or cerebellumcerebellum

Chronic Epidural HematomaChronic Epidural Hematoma

The hematoma spontaneously shrinks and The hematoma spontaneously shrinks and becomes encapsulated by fibrous becomes encapsulated by fibrous connective tissue.connective tissue.

SubduralSubdural

BleedingBleeding

Subdural bleedingSubdural bleeding

Trauma Trauma

Rupture of aneurysmRupture of aneurysm

Arteriovenous malformationArteriovenous malformation

Vein:Vein:

- Tearing of one or - Tearing of one or

- Several bridging vein- Several bridging vein

- Insignificant trauma- Insignificant trauma ( (sometimesometime)): :

abnormally located blood vessels abnormally located blood vessels

Artery:Artery:

- particularly in branches of the middle - particularly in branches of the middle cerebral arterycerebral artery

- severe cortical contusions and bleeding - severe cortical contusions and bleeding

into subarachnoid space:into subarachnoid space: ((usuallyusually)) tears of arachnoid membrane tears of arachnoid membrane

ArteryArtery::

- More frequently on the side opposite - More frequently on the side opposite

the impactthe impact

- - ((MayMay)) without brain contusions without brain contusions

or significant subarachnoid hemorrhage or significant subarachnoid hemorrhage

Time of onsetTime of onset

AcuteAcute: within 12 to 24 hr. : within 12 to 24 hr.

SubacuteSubacute: from 24 hr. to 7 d.: from 24 hr. to 7 d.

ChronicChronic: more than 7 d.: more than 7 d.

Most Location: over the convexities and the Most Location: over the convexities and the laterallateral aspects of the cerebral hemisphereaspects of the cerebral hemisphere

Often: Often: extend over the base of frontal and extend over the base of frontal and

temporal lobestemporal lobes

Occasionally: between the hemisphereOccasionally: between the hemisphere

In skull intact: occur as often as with skull In skull intact: occur as often as with skull fracturefracture

Rare in the posterior cranial fossa , around Rare in the posterior cranial fossa , around the brain stem and cerebellumthe brain stem and cerebellum

Chronic Subdural HematomaChronic Subdural Hematoma

Enlargement if untreatEnlargement if untreat

Isotonicity Isotonicity

Local presence of fibrinolytic enzymes: Local presence of fibrinolytic enzymes: bleeding tendencybleeding tendency

SubaracnoidSubaracnoid

BleedingBleeding

Subaracnoid bleedingSubaracnoid bleeding

Trauma / NontraumaTrauma / Nontrauma

Extension of intraventricular hemorrhageExtension of intraventricular hemorrhage

Moderately severe blow to the face or Moderately severe blow to the face or foreheadforehead

Sudden ,usually severe hyperextension of Sudden ,usually severe hyperextension of the head , as from a fall onto the foreheadthe head , as from a fall onto the forehead

Subarachnoid over the brain stem and Subarachnoid over the brain stem and basal cisterns = hydrocephalusbasal cisterns = hydrocephalus

Forgetfulness , confusion , psychotic state Forgetfulness , confusion , psychotic state

Spasticity of the lower extremitiesSpasticity of the lower extremities

IntraventricularIntraventricular

bleedingbleeding

IntraventricularIntraventricular bleedingbleedingMost often arterial in originMost often arterial in origin

Trauma Trauma

Non-trauma: such as rupture AVM or Non-trauma: such as rupture AVM or AneurysmsAneurysms

IntracerebralIntracerebral

LesionsLesions

ContusionsContusions

Lacerations Lacerations ((WoundsWounds))

ContusionsContusions

Contusion hemorrhageContusion hemorrhage

Contusion necrosisContusion necrosis

Contusion tearContusion tear

Intracerebral HematomaIntracerebral Hematoma

In the deeper portions of contusionsIn the deeper portions of contusions

More frequent in the frontal and /or More frequent in the frontal and /or temporal lobestemporal lobes

Location: white matter > grey matterLocation: white matter > grey matter

Intracerebral HematomaIntracerebral Hematoma

Secondary rupture into the ventricular Secondary rupture into the ventricular system and/or the subarachnoid space system and/or the subarachnoid space usually does not occur.usually does not occur.

LacerationsLacerations

Stab woundsStab wounds

Gunshot woundsGunshot wounds

Gunshot woundsGunshot wounds

Shearing forces within brain tissueShearing forces within brain tissue

Expansile cavitationExpansile cavitation

Distant contusions Distant contusions ((hemorrhageshemorrhages))

ClassificationClassification ofof

ContusionsContusionsAccording to According to

causative causative mechanismmechanism

Depending on site and direction of impactDepending on site and direction of impact

: Coup , Intermediary coup , Contrecoup: Coup , Intermediary coup , Contrecoup

Independent of site and direction of impactIndependent of site and direction of impact

: Fracture contusion , Gliding contusion , : Fracture contusion , Gliding contusion ,

Herniation contusionHerniation contusion

Axonal injuryAxonal injuryShearing forces due to blunt head injuriesShearing forces due to blunt head injuries

Focal , diffuse Focal , diffuse

Early ,the areas: little or no change on Early ,the areas: little or no change on gross examination of the white mattergross examination of the white matter

Older lesions: slightly gray pallor Older lesions: slightly gray pallor

22๐๐ AlterationsAlterations

22๐๐ AlterationsAlterations

Circulatory disorderCirculatory disorder

Necroses and hemorrhagesNecroses and hemorrhages

Post-traumatic hydrocephalusPost-traumatic hydrocephalus

Secondary infectionsSecondary infections

Fat and air embolismFat and air embolism

Circulatory disorderCirculatory disorderSwelling of the brain: edema and cell Swelling of the brain: edema and cell necrosisnecrosis

Usually reversibleUsually reversible

Perifocal: surrounding a 1Perifocal: surrounding a 1๐๐ brain lesionbrain lesion

Generalize: a primary lesion , shockGeneralize: a primary lesion , shock

Other rare causesOther rare causes

Obstruction of the superior sagittal sinusObstruction of the superior sagittal sinus

Traumatic thrombus or obstruction in Traumatic thrombus or obstruction in internal carotid artery internal carotid artery

Necroses/HemorrhagesNecroses/Hemorrhages

Vascular compressionVascular compression

Shearing lesionsShearing lesions

Necroses/HemorrhagesNecroses/HemorrhagesMany lesion are large: such as midbrain Many lesion are large: such as midbrain and ponsand pons

If rapidly progressing space occupying If rapidly progressing space occupying lesion: secondary lesion may appear lesion: secondary lesion may appear within 30 mins. After injurywithin 30 mins. After injury

Hemorrhage : sometimes small or absentHemorrhage : sometimes small or absent

HydrocephalusHydrocephalusTraumatic or Non-traumaticTraumatic or Non-traumatic causecause

White matter loss following a shearing White matter loss following a shearing lesion and degeneration of myelinated lesion and degeneration of myelinated axonsaxons

Distension of ventricles by elevated Distension of ventricles by elevated pressure of the CSFpressure of the CSF

Secondary infectionsSecondary infections

Meningitis Meningitis

Intracerebral abscessesIntracerebral abscesses

MeningitisMeningitis

An infected open injury caused by a An infected open injury caused by a foreign bodyforeign body

A fracture in the wall of one of the cranial A fracture in the wall of one of the cranial sinuses associated with a tear in the dura sinuses associated with a tear in the dura and arachnoidand arachnoid

Intracerebral abscessesIntracerebral abscesses

In the vicinity of the primary lesionIn the vicinity of the primary lesion

Complication: rupture into the underlying Complication: rupture into the underlying ventricle ventricle ((PyocephalusPyocephalus))

Fat and air embolismFat and air embolism

Primary or Secondary lesionsPrimary or Secondary lesions

Fat embolism: fractures , stab wound at Fat embolism: fractures , stab wound at neckneck

Air embolism: stab wound at neck , a skull Air embolism: stab wound at neck , a skull fracture lacerating a paranasal dural sinusfracture lacerating a paranasal dural sinus