Lecture 16: TBI, Vascularization and Stroke Flashcards
What is traumatic brain injury?
Insult to brain caused by external physical force (not degenerative or congenital nature). May produce a diminished or altered state of consciousness. May result in an impairment in cognitive abilities or physical functioning
Prognosis for Brain Injury
younger, shorter coma, shorter post traumatic amnesia (anterograde), small brain injury, location based (damage in CNS or not), cause of injury (fall v. gun)
Fun fact about TBI
Males 15-24 at higher risk followed by elderly, infants. Motor vehicles biggest cause followed by falls and violence/sports injuries
Skull intact, no penetration of skull
Closed head injury TBI
Penetration of skull with direct injury
Open head injury TBI
What is most common type of TBI?
Focal injury (local, damage to specific area). Direct impact of short duration related to deceleration/acceleration ex) coup-contra-coup (usually seen with diffuse axon injury)
Coup-contra-coup
Brain hurled against skull then ricochets in oppo. direction (frontal and temporal most often damaged (under focal injury)
Contusion
Bruises
Diffuse axonal injury
Stretch injury to membrane of axon, leading to axon breakage (Diffuse injury)
Secondary damage is increased intracranial pressure, swelling hemorrhage, oxygen deprivation
Diffuse injury (TBI)
Damage is diffuse and impact several areas, occur from hypoxia, damage in blood vessels
Diffuse Injury (TBI)
Hematoma
localized collection of blood, usually clotted in tissue or organ (epidural, subdural, intracerebral)
Epidural hematoma
above dura (between brain and skull)
Subdural hematoma
Below dura
Intracerebral hematoma
Inside brain
Coma
state person makes no purposeful response to environment and rom which she can’t be aroused (may last hours or days) followed by semi coma (confusion)
Glasgow Coma Scale
way to record conscious state of person. 15 is awake (us), and 3 is death, deep coma (tests eye, verbal, motor)
State of inconsistent, erratic responsiveness generally unable to communicate with outside world
Minimally conscious state
TBI cognitive impairment consists of…
diminished mental processing speed, difficulty with divided attention, difficulty with executive functions
Where is damage if you have dysarthria?
Right or left. It is slurred speech, mechanical issue, damage to motor cortex/cranial nerves/corticobulbar
Where is damage if you have aphasia?
Generally damage to LEFT hemisphere (Broca’s, Wernicke’s, global) Deficit in language
Anterograde Amnesia
More common esp. after injury and comma (can be period or days) can’t remember moment of injury and things after.
Where is damage if you have spasticity, atypical reflexes?
upper motor neuron/hyper reflexia
Where is damage if you have poor balance and equilibrium?
Cerebellum
Where is damage if you have abnormal postures?
Descending motor, basal ganglia
Where is damage if you have difficulty swallowing?
Cranial Nerves
Where is damage if you have tremors?
Resting tremor (basal ganglia), intention tremors (cerebellum)
Where is damage if you have Athetosis?
Basal Ganglia (involuntary writhing movements)
Damage to ventral and medial prefrontal association cortices?
Personality/Emotion: poor judgment, irritability, apathy, altered sex drive, decreased goal directed, impaired social skills, emotional lability, limited self awareness
Where is damage if you have apraxia?
Damage in left hemisphere (left PTO)
Where is damage if you have unilateral neglect?
Damage to right PTO
Where is damage if you have visual spatial, poor body awareness?
Damage to right PTO
Where is damage if you have constructional apraxia?
Right PTO
What are the two paired arteries from aorta that supply blood to brain?
Internal Carotid (anterior) and Vertebral-basilar (posterior)
Role of Internal Carotid artery?
Anterior supply, supplies majority of cerebral hemispheres
Role of Vertebral Basilar artery?
posterior supply, supplies brainstem, cerebellum and some of the cerebral hemisphere - two vertebral merge to form basilar
Circle of Willis
Branches of internal carotid and basilar arties form circle ( 2 posterior, 2 anterior, 2 middle cerebral arteries, and 3 communicating arteries. Circulatory anastomosis that supplies blood to the brain and surrounding structures
What is anastomosis?
Ring of 9 arteries that supply all blood to brain (6 large, 3 communicating arteries)
Internal Carotid branches into…
Anterior cerebral (middle) and Middle Cerebral (lateral)
Basilar artery branches into…
posterior cerebral
What is from the internal carotid, and supplies lateral surface of most of lateral hemispheres: frontal, parietal and temporal lobes (except for inferior temp. lobes)
Middle Cerebral Artery
What branches penetrate and supply deep structures of internal capsule, basal ganglia, optic tract, and radiations?
Middle Cerebral Artery
Damage to Middle Cerebral Artery leads to…
Everything but memory is impaired:
- Motor (contralateral hemiplegia, UE/face most affected)
- Sensory (contralateral hemianesthesia (UE/face most affected)
- Language (L. aphasia/L. aprosodia, and R/L mechanical disorder of speech disarthria)
- Perceptual (R. Agnosia, difficulty with spacial relationship, left neglect, constructional apraxia. L. apraxia)
- Vision: contralateral homonymous hemianopia
- MEMORY FINE
- Emotion/behavior: change in emotion/personality and often times executive functioning
What artery supplies medial aspects of frontal and parietal lobes?
Anterior Cerebral Artery
What artery branches to diencephalon, limbic, caudate, internal capsule (undersurface of parietal lobe and part of frontal)
Anterior Cerebral Artery
Damage to Anterior Cerebral Artery leads to…
Motor: Contralateral hemiplegia (LE most affected)
Sensory: contralateral hemianesthesia (LE most affected)
Language/Perception/Vision/Visual/Memory fine
Emotion/behavior: Changes in emotion, personality, executive functions
What artery supplies undersurface and posterior surface of temporal and occipital lobes?
Posterior Cerebral Artery
Damage to Posterior Cerebral Artery leads to…
Motor, sensory, language, perception, emotion fine.
- Vision (CHH)
- Memory loss
What artery damage can lead to memory loss?
Posterior Cerebral Artery (PCA)
What artery damage can lead to contralateral homonymous hemianopia?
MCA, PCA
What artery damage can lead to contralateral hemiplegia and hemianesthesia?
ACA (lower extremities, MCA (upper extremities and face most affected)
What artery damage can lead to emotion/behavior change?
ACA and MCA
What artery damage can lead to language deficit?
MCA
What artery damage can lead to perceptual deficits?
MCA (maybe ACA if left)
Where does basilar artery run along?
Surface of brainstem at level of pons
Where does basilar artery wrap around?
Cerebellum and internal auditory artery
Complete occlusion (blockage) of Basilar artery leads to…
death due to ischemia of brainstem nuclei and tracts that control vital functions
What is ischemia?
an inadequate blood supply to an organ or part of the body,
Partial occlusion (blockage) of Basilar artery leads to…
tetraplegia (BILATERAL since it is one artery), loss of sensation, coma, CN signs
Severe partial occlusion of basilar artery leads to…
Locked-in syndrome (diving bell and butterfly) Awake, aware but can’t community, paralysis in all body
Damage to cerebellar arteries lead to…
bad balance, lack of coordination, nystagmus, dizziness (superior, anterior inferior, posterior interior)
Arteries part of Anterior Supply:
Internal carotid system: MCA ACA
Arteries part of Posterior Supply:
Vertebral Basilar System: PCA, Cerebellar arteries
What is local, temporary loss of blood supply called?
Ischemia (lose consciousness after 10 secs, electrical signal ceases after about 20 seconds)
Ischemia
local, temp. loss of blood supply
Infarct
area of tissue death due to loss of blood supply (if in same damage, TBI and stroke looks familiar)
What is cerebrovascular accident (CVA)?
Focal neurological disorder of relatively abrupt onset due to a pathological process in blood vessel, usually within ONE hemisphere of brain (loss of blood supply/problem with blood vessel, happens in one hemisphere)
This is a focal neurological disorder due to problem with blood vessel (loss of blood) in one hemisphere
Cerebrovascular accident (also known as stroke/brain attack)
What is the leading cause of serious long term disability?
Stroke
What is transient ischemic attack (TIA)?
Brief, focal loss of brain function (usually recovery within 24 hours, sign of risk for stroke)
Brief, focal loss of brain function which recovery within 24 hours is called…
TIA (transient ischemic attack)
Neurologic deficits from vascular disorders that persist more than 1 day and stable
Completed stroke
If you have this, there will be a stroke in next three months.
Transient Ischemic Attack
With this type of stroke, you are not getting better or worse.
Completed stroke
Progressive stroke
Deficits increase intermittently over time (little strokes)
Small little strokes
Progressive stroke
What are the different types of strokes?
- Brain infarction
2. Hemorrhagic Stroke
Brain Infarction
caused by blockage of blood vessel producing ischemia, resulting in infarct (tissue death)
90% of strokes are…
ischemic
What causes blockage?
Thrombus: formation of blood clot within artery (and stays there)
What kind of stroke where formation of blood clots within artery?
Thrombotic stroke
What is embolic stroke?
Blood cot formed, was dislodged, trailed in blood stream and then became trapped in arteries closer to brain.
Embolism
Clot travels from site where it was formed
Thrombus
blood clot that forms in a vessel
Hemorrhagic Stroke
Rupture of blood vessels, with bleeding into/around cerebral tissue. Bleeding irritates brain tissue causing swelling. Surrounding tissue of brain resist expansion of bleeding and contains it, forming a mass (hematoma). Swelling and hematoma will compress and displace normal brain tissue
Infarct Stroke v. Hermorrhagic
Blockage of blood resulting in tissue death v. Rupture of blood vessel, bleeding leads to swelling
Causes of Hemorrhagic stroke
High Blood Pressure, aneurysm (weak spot in artery wall), amyloid protein
What is an aneurysm?
Weak spot in artery wall, balloons out because of pressure of blood circulating, bursts and causes harm
What is amyloid protein?
Makes vessels more prone to bursting (common in elderly)
What is a weak spot in artery wall, balloons and bursts?
Aneurysm
What makes vessels more prone to bursting? Common in elderly?
Amyloid Protein
What are risk factors for stroke?
Hypertension, high cholesterol, diabetes, overweight, high alcohol intake, smoking, stress (lifestyle changes can reduce risk of stroke)
What are some stroke symptoms?
weakness to move body part, numbness of sensation, decrease vision, speech difficulties, inability to id familiar things, sudden headache, dizziness, loss of coordination, swelling difficulties, sleepy
F- face uneven
A- arm (one)
S- speech slurred
T- time to call 911
weakness to move body part, numbness of sensation, decrease vision, speech difficulties, inability to id familiar things, sudden headache, dizziness, loss of coordination, swelling difficulties, sleepy are symptoms of…
stroke
Common deficits of stroke?
Motor - muscle tone is flaccid then spasticity, hyperreflexia, paralysis, hemiplegia, apraxia
Sensory - rarely in isolation, depend on where it is, have motor too
Visual - CHH
Emotional - depression, apathy, fear, frustration, emotional lability
What happens to muscle tone in stroke?
Flaccid at first then spasticity (velocity dependent hypertonia). UE flexor syngery tend to be: shoulder adducted, elbow/wrist/finger flexion with supination while LE extended throughout limb
What happens to reflexes in stroke?
Hyperreflexia (because UMN can’t turn off)
What happens to perception in stroke?
Agnosia, body scheme, visual spatial, constructional praxis
What happens to language in stroke?
Aphasia and dysarthria
ACA
- Motor: contralateral hemiplegia (LE)
- Sensory: contralateral sensory loss (LE)
- Language: n/a
- Perception: L hemi possibly apraxia
- Visual: n/a
- Memory: n/a
- Emotion/Behavior: difficulty with exec fxning & divergent thinking, possibly personality changes
MCA
- Motor: contralateral hemiplegia (UE/face)
- Sensory: contralateral sensory loss (UE/face)
- Language: aphasia (if L hemisphere), impairment in nonverbal communication (if R hemi)
- Perception: R hemi: diff with spatial rltnshps, neglect, agnosias, constructional apraxia etc.; L hemi: apraxia
- Visual: CHH if optic tract/radiations
- Memory: n/a
- Emotions/Behavior: difficulty with exec fxning & divergent thinking, impulsive, personality changes, etc.
PCA
- Motor: minimal involvement (if yes, contralateral hemiplegia)
- Sensory: minimal involvement (if yes, contralateral hemianesthesia)
- Language: n/a (if motor involvement above, though, may have dysarthria)
- Perception: n/a
- Visual: CHH
- Memory: memory loss
- Emotions/behavior: n/a
Basilar
• Motor: bilateral weakness or paralysis
• Sensory: bilateral sensory loss
• Language: dysarthria
• Cerebellar signs: vertigo, dizziness, nystagmus
• Locked-in syndrome
• (not a symptom, but if a complete occlusion = death)
(pons, cerebellum)
This branches and supply part of optic chiasm, optic tract, parts of thalamus
Posterior Cerebral Artery
“Harry has hemianesthesia and hemiplegia (UE face impacted). He greets you in garbled, halting phrases and grammatical function words. He can follow simple commands but can’t express himself.” Which hemisphere has lesion?
Left
“Harry has hemianesthesia and hemiplegia (UE face impacted). He greets you in garbled, halting phrases and grammatical function words. He can follow simple commands but can’t express himself.” What is name of his communication difficulty?
Broca’s Aphasia
“Harry has hemianesthesia and hemiplegia (UE face impacted). He greets you in garbled, halting phrases and grammatical function words. He can follow simple commands but can’t express himself. “ What side of his body is he experiencing sensory or motor loss on?
Right
“Harry has hemianesthesia and hemiplegia (UE face impacted). He greets you in garbled, halting phrases and grammatical function words. He can follow simple commands but can’t express himself.” If his cause of symptoms was stroke, what artery would be implicated?
Left MCA
“Sarah feels weakness on one side of body, confusion, difficulty swallowing then feels 100% normal again. She can make tea on her own. But when they are at the hospital cafeteria, son asks her to make tea and she can’t.” What do you think happened to cause symptoms she experienced?
Transient Ischemic Attack
“Sarah feels weakness on one side of body, confusion, difficulty swallowing then feels 100% normal again. She can make tea on her own. But when they are at the hospital cafeteria, son asks her to make tea and she can’t.” Was it necessary to go to hospital?
Yes because she is at higher risk for CVA stroke.
“Sarah feels weakness on one side of body, confusion, difficulty swallowing then feels 100% normal again. She can make tea on her own. But when they are at the hospital cafeteria, son asks her to make tea and she can’t.” What deficit is associated with her making cup of tea?
Ideomotor Limb Apraxia
“Sarah feels weakness on one side of body, confusion, difficulty swallowing then feels 100% normal again. She can make tea on her own. But when they are at the hospital cafeteria, son asks her to make tea and she can’t.” Where is Sarah’s lesion?
Left Premotor and Suppl Motor.
