15.5: Key Terms

aphasia

loss of language skills affecting expression (Broca’s), comprehension (Wernicke’s), or both (global), depending on the area of brain damage

apraxia

inability to perform tasks, movements, or gestures

arteriovenous malformation (AVM)

abnormal formation of blood vessels in which the arteries and veins can become tangled and form connections

central nervous system (CNS)

body’s processing and functional control center

cerebral embolism

obstruction in which a clot forms elsewhere in the body, breaks off, and travels to the blood vessels of the brain

cerebral thrombus

clot within a blood vessel that blocks cerebral perfusion

cerebrovascular accident (CVA)

interruption in blood flow to cells within the brain; commonly referred to as a stroke

cerebrovascular embolus

clot that forms elsewhere in the body, breaks off, and travels to the blood vessels of the brain

circle of Willis (CoW)

location in the brain where cerebral arteries meet and divide in a way aimed to maintain perfusion

cryptogenic stroke

stroke for which the cause cannot be determined

dysarthria

trouble speaking

dysphagia

trouble swallowing

Glasgow Coma Scale (GCS)

objective measurement scale that rates impairment of consciousness by scoring in three areas: eye opening, verbal response, and movement

hemiparesis

weakness on one side of the body

hemiplegia

complete paralysis on one side of the body

hemorrhagic stroke

bleeding into the brain caused by the rupture of a blood vessel

hemorrhagic transformation

occurrence of a hemorrhagic infarct after an ischemic stroke, particularly after the administration of tPA

homonymous hemianopsia

deficit causing a loss of vision in the same halves of the visual field in each eye

hydrocephalus

increase in cerebrospinal fluid in the ventricles of the brain

infarct

area of necrotic tissue in the brain

intracerebral hemorrhage (ICH)

hemorrhage, or bleed, within the cerebral vasculature and brain tissue

intracranial hemorrhage

hemorrhage, or bleed, in the cranium

ischemic stroke

type of stroke in which a clot prevents blood flow to part of the brain

lacunar stroke

small artery thrombosis

locked-in syndrome

rare condition in which patients retain consciousness but develop paralysis of the entire body except in the muscles of eye movement

mass effect

compression of and injury to surrounding brain tissue because of hematoma

midline shift

displacement of brain tissue across the midline

nystagmus

rapid, uncontrolled eye movements

patent foramen ovale

small hole between the left and right atria to support fetal circulation that closes on its own in most cases

penumbra

tissue that is immediately around an infarction, is receiving marginal blood flow, and is still salvageable with restoration of perfusion

permissive hypertension

post-stroke condition in which the patient is allowed to maintain a higher blood pressure to support perfusion

perseveration

continuous and repetitive speech, behavior, or thoughts

proprioception

awareness of one’s own body position and movement in relation to the space around oneself

subarachnoid hemorrhage (SAH)

hemorrhage, or bleed, that occurs in the subarachnoid space surrounding the brain

thrombectomy

procedure in which a catheter is inserted through a vessel to physically remove a clot from the cerebral vasculature

thunderclap headache

severe, sudden headache that peaks in intensity in seconds, lasts at least five minutes, and lingers and fades within a few hours

tissue plasminogen activator (tPA)

medication administered intravenously to break up a blood clot responsible for stopping cerebral blood flow

transient ischemic attack (TIA)

temporary occlusion of the blood vessels perfusing parts of the brain, after which the clot dislodges or dissolves on its own, restoring perfusion; sometimes called a "mini-stroke"

ventriculostomy

procedure in which a hole is drilled through the skull and a catheter for measuring pressure is placed directly into the ventricle