Stroke Basics
This artery supplies the lower limb extremity motor strip
What is the anterior cerebral artery (ACA)?
This type of stroke syndrome leads to tetraparesis with ability to only move eyes vertically or blink.
What is Locked-in syndrome?
Due to bilateral lesions of the ventral pons. Patients remain fully conscious due to sparing of reticular activating system (located primarily in midbrain).
Source: Cuccurullo
This is the formation of mature lamellar bone in extra skeletal soft tissues
What is heterotopic ossification?
This type of TBI results from the shearing of the bridging veins between the pia-arachnoid and the dura.
What is a subdural hematoma (SDH)?
Other types of brain hemorrhages:
-Subarachnoid hemorrhage: associated with ruptured cerebral aneurysms and AVMs, or from leakage from intraparenchymal hemorrhage
-Epidural hematoma: associated with skull fractures in the temporal bone with involvement of the middle meningeal artery or veins
This is assessed on the Galveston Orientation and Amnesia Test (GOAT)
What is post traumatic amnesia (PTA)?
"The end of PTA can be defined as the date when the patient scores 75 or higher in the GOAT for two consecutive days."
Source: Cuccurullo
The artery that supplies the posterior inferior surface of the temporal lobe and the visual cortex
What is the posterior cerebral artery (PCA)?
This type of lacunar stroke often involves weakness in the face, arm, and leg; there is no sensory deficits, aphasia, or parietal signs.
What is pure motor hemiplegia?
Lesions usually are in the posterior limb of the internal capsule, corona radiata, or pons.
This medication which can be used to treat spasticity acts at the muscle level blocking the release of calcium at the sarcoplasmic reticulum.
What is dantrolene?
The vertebral artery originates and branches off from this large artery.
What is the subclavian artery?
Severe TBI is characterized by this GCS score range.
What is GCS score of 3 to 8?
Mild TBI: 13-15
Moderate TBI: 9-12
Severe TBI: 3-8
The most important modifiable risk factor for both ischemic and hemorrhagic strokes
What is hypertension?
"Subjects with BP lower than 120/80 mmHg have about half the lifetime risk of stroke compared to subjects with high BP."
Source: Cuccurullo
Common symptoms of this syndrome include: agraphia, acalculia, finger agnosia, and left-right disorientation.
What is Gerstmann syndrome?
Due to lesion in the parietal lobe of the dominant hemisphere.
This type of brain injury results from axonal shearing from acceleration-deceleration rotational forces
What is diffuse axonal injury?
This system that is located in the upper brainstem with projections to widespread areas of the cerebral cortex is essential in maintaining consciousness.
What is the reticular activating system (RAS)?
"Lesions that interrupt the integrity of the RAS or enough of the neurons receiving RAS input can cause disorders of consciousness."
~Cuccurullo
A posttraumatic amnesia (PTA) duration of 1 to 24 hours classifies TBI into this severity.
What is moderate TBI?
PTA equal or less than 1 hour: mild TBI
PTA between 1 to 24 hrs: moderate TBI
PTA between 1 to 7 days: severe TBI
PTA between 1 to 4 weeks: very severe TBI
Source: Cuccurullo
A common impairment seen with a lesion in the inferior division of the right MCA
Left visual neglect
Signs and symptoms of this stroke syndrome include ipsilateral Horner's and decrease in pain/temperature sensation on ipsilateral face and contralateral body.
What is Wallenberg (Lateral Medullary) Syndrome?
Other symptoms can include: ipsilateral cerebellar signs such as ataxia, dysphagia, dysarthria, vertigo, diplopia. There is NO facial or extremity muscle weakness in this syndrome!
Source: Cuccurullo
This dopamine D2-receptor blocker can have the serious side effect of agranulocytosis.
What is clozapine?
Antipsychotics often used for agitation in TBI, must be cautious of side effects which can include neuroleptic malignant syndrome, tardive dyskinesia, metabolic derangements, QT prolongation, and anticholinergic side effects.
Aside from the cerebral white matter and midbrain, this region of the brain is one most frequently affected in diffuse axonal injury (DAI).
What is the corpus callosum?
Common locations of DAI:
1) Cerebral white matter
2) Corpus callosum
3) Midbrain
Source: Cuccurullo
DAILY DOUBLE
This type of disorder of consciousness is characterized by resumption of the sleep-wake cycle on EEG. Other characteristics include: no awareness of self/environment, no purposeful behavior, but patient can open eyes spontaneously or with noxious stimuli.
What is the vegetative state?
1) Coma: lack of sleep/wake cycles on EEG. There is no spontaneous purposeful movement, patient's eyes remain closed and no evidence of language.
2) Minimally conscious state: patient displays some evidence of self/environmental awareness and inconsistent but reproducible purposeful behavior such as simple command following, tracking, etc.
This type of aphasia is characterized by good comprehension, good repetition, and reduced rate of speech as well as limited language output.
What is transcortical motor aphasia?
Other types of nonfluent aphasias:
1) Broca's aphasia: also has good comprehension but with poor repetition
2) Mixed transcortical aphasia: poor comprehension but good repetition
3) Global aphasia: poor comprehension, poor repetition.
This type of paramedian brainstem stroke syndrome leads to ipsilateral CN 3 palsy and contralateral hemiplegia
What is Weber syndrome?
Types of Paramedian (Medial) Brainstem Strokes:
1) Weber syndrome: ipsilateral CN3 palsy and contralateral hemiplegia. Due to midbrain lesion.
2) Millard-Gubler syndrome: ipsilateral CN6 and 7 paralysis, contralateral hemiplegia and sensory loss. Due to pontine lesion.
3) Medial Medullary syndrome: Ipsilateral CN12 palsy, contralateral hemiplegia and sensory loss. Due to medullary lesion.
Source: Cuccurullo
The equation to calculate CPP (cerebral perfusion pressure)
MAP - ICP = CPP
Increased ICP reduces cerebral blood perfusion. CPP should remain > 60 mmHg to ensure adequate cerebral blood flow.
Source: Cuccurullo
This type of posturing is seen in midbrain, cerebellar, and posterior fossa lesions where the patient has both upper and lower limbs held in extension.
What is decerebrate posturing?
Compared to decorticate posturing where the patient has upper limbs in flexion and lower limbs in extension. This type of posture is seen in higher lesions such as in the cerebral hemisphere, internal capsule, and thalamus.
Source: Cuccurullo
What is Cerebral salt-wasting (CSW) syndrome?
In CSW, hyponatremia is not dilutional (as in SIADH), CSW patients are volume depleted and display signs of dehydration. Treatment is fluid replacement and electrolyte correction, not fluid restriction.
Source: Cuccurullo