IFS Unit 3: Cerebral Perfusion, Arteries, and the Blood-Brain Barrier

This set covers the vascular supply of the brain (ACA, MCA, PCA), cerebrospinal fluid dynamics, and the physiological structures of the Blood-Brain Barrier.

Cerebral Blood Flow Rate

The brain receives approximately $600-750\,mL/min$ of blood flow.

Internal Carotid Arteries

One of the four main pipes supplying the brain, specialized for internal brain supply.

External Carotid Artery

The artery that goes towards the face skin.

Vertebral Artery

An artery that travels up the transverse foramina on the spinal column and enters the posterior circuit through the foramen magnum.

Optic Chiasm

The landmark used to differentiate the anterior circuit from the posterior circuit.

Middle Cerebral Artery (MCA)

The most common artery for strokes; it supplies half of the brain mass and is divided by the Sylvian line.

MCA Superior Division

The division responsible for motor and sensory functions to the face, arm, hand, and Broca's area.

MCA Inferior Division

The division responsible for speech and language comprehension.

Anterior Cerebral Artery (ACA)

Supplies the leg, foot, trunk, hip, genitals, motor/sensory cortex, and the cingulate gyrus/limbic system.

Posterior Cerebral Artery (PCA)

An artery arising from the vertebral circuit (not the internal carotid) that hooks behind the midbrain to supply the occipital lobe and the thalamus.

Cerebrospinal Fluid (CSF)

Fluid that bathes, cushions, and provides shock absorption for the nervous system while creating hydrostatic pressure.

Normal CSF Pressure

$11\,mm$ of mercury.

Choroid Plexus

Structures produced by the pia mater that produce cerebrospinal fluid.

Arachnoid Mater

The layer that absorbs waste from the cerebrospinal fluid.

Blood Brain Barrier (BBB)

A regulatory barrier composed of ependymal cells and tight junctions that controls what enters the brain.

Astrocytes

Support cells that are critical in forming the Blood Brain Barrier.

Water Soluble Chemicals in the Brain

Chemicals such as glucose, water, and sodium that are actively regulated by tight junctions and move from high to low concentration.

Lipid Soluble Molecules

Molecules that easily pass through the phospholipid bilayer into the brain; this is primarily how drugs are moved into the brain.

Blood CSF Layer

An alternative pathway into the brain; if a particle passes through this layer unchecked, it goes straight to the brain.