Neuro Exam 3

Ischemia

reduced supply or unavailability of blood; leads to cell death

Vascular interruption

for 4 to 6 minutes results in irreversible brain damage.

Hippocampus

particularly sensitive to interruptions in blood supply.

Arteries

carry oxygenated blood to the brain.

Veins

return the deoxygenated blood back to the heart for reoxygenation.

Hypoxia (Hypoxemia)

low arterial oxygen supply.

Anoxia

condition of oxygen deficiency in brain tissue.

Cerebrovascular Supply

Two arterial systems: Carotid and Vertebral-basilar.

Circle of Willis

serves to equalize the vascular blood supply to both sides of the brain.

Anterior cerebral artery (ACA)

supplies the orbital and medial cortical surfaces of the prefrontal, frontal, and parietal lobes.

Middle cerebral artery (MCA)

supplies blood to entire lateral surface of the brain, including precentral gyrus, postcentral gyrus, primary auditory cortex, auditory association cortex, basal ganglia.

Posterior cerebral artery (PCA)

supplies blood to parts of temporal and occipital lobes, hippocampus, visual association cortex.

Blood supply to the spinal cord

by two major longitudinal arteries: anterior spinal arteries and posterior spinal arteries.

Cerebrovascular accidents (CVA)

strokes.

Types of strokes

Embolic strokes (25%), Thrombotic strokes (65%), Hemorrhagic strokes (10%).

Transient ischemic attack (TIA)

a temporary interruption of blood circulation to the brain.

Warning signs of stroke

sudden onset of numbness or weakness on one side of the body, sudden inability to speak and understand others, sudden difficulty in seeing with one or both eyes; double vision, sudden loss of balance and dizziness, headache with no cause.

Ischemia risk factors

hypertension, heart disease, diabetes (type II), high cholesterol, smoking, obesity, eating habits, physical inactivity.

Treatment of vascular diseases

Goals of medical management of a stroke: restore normal blood circulation, contain the infarct and its effect, control poststroke complications.

Clot-busting drug (tPA)

may be administered in case of occlusive stroke.

The Blood-Brain Barrier

restricts the movement of harmful substances from entering the brain.

Cerebrospinal fluid

Clear fluid produced by choroid plexus in ventricles.

Choroid plexus

Structure in ventricles that produces cerebrospinal fluid.

Cerebrospinal fluid volume

Average volume is 120-140 mL in the brain.

Ventricular system

Network where cerebrospinal fluid circulates in the brain.

Interventricular foramen of Monro

Passage connecting lateral ventricles to third ventricle.

Cerebral aqueduct

Channel draining third ventricle to fourth ventricle.

Central canal

Continuation of fourth ventricle into the spinal cord.

Subarachnoid space

Area around CNS where cerebrospinal fluid circulates.

CSF drainage

Process where CSF moves to superior sagittal sinus.

Hydrocephalus

Condition of excessive cerebrospinal fluid in the brain.

Increased Intracranial Pressure

Excess CSF causes pressure increase in the brain.

Arnold-Chiari malformation

Congenital condition affecting brain development in infants.

Communicating hydrocephalus

Inadequate CSF drainage into sinus, often due to meningitis.

Obstructive hydrocephalus

Blocked CSF flow from ventricles to subarachnoid space.

Cerebral aqueduct blockage

Most common site for obstructive hydrocephalus.

Surgical shunt

Device to redirect blocked CSF for absorption.

Lumbar puncture

Procedure to draw CSF from L3 to S1 vertebrae.

CSF pressure measurement

Assessment indicating brain swelling or tumors.

Chemical analysis of CSF

Tests for infections like bacterial meningitis.

Spinal anesthesia

Anesthesia administered via lumbar puncture procedure.