PTA 160 - The Cerebrospinal Fluid System

What is the the Cerebrospinal Fluid System function

Protective cushion around the brain

where does the cerebral spinal fluid circulate

the ventricles and in the subarachnoid space(brain and spinal cord)

what does the cerebral spinal fluid provide

protective cushioning for brain against forces associated with surface contact pressure and sudden movements.

when does the 3rd ventricle begin

after the Foramen of Monroe (a small opening that connects each lateral ventricle to the third ventricle

what does the 3rd ventricle allow

cerebrospinal fluid (CSF) to flow from the lateral ventricles into the third ventricle

and empties into the Cerebral aqueduct

What is the Cerebral Aqueduct

A TUBULAR CANAL

where is the cerebral aqueduct located

midbrain

what is the narrowest part of the midbrain

cerebral aqueduct

what does the cerebral aqueduct connect

THE 3RD AND 4TH VENTRICLES

what does the Cerebral Aqueduct drain

CSF from the 3rd ventricle

What happens in the 4th ventricle

CFS leaves ventricular system

when CFS leaves the 4th ventricle where does it go

into the cisterna cerebellomedullaris by way of the foramen of magendi

Subarachnoid space is continuous across the

cerebellar and cerebral convexities and along the spinal cord.

What all does the subarachnoid space carry

arteries, extra cerebral arteries and veins and Cranial nerves (web-like slings)

CISTERNS

expansions in the subarachnoid space brain and spinal cord

Cisterns purpose

helps to cushion the brain and provides support and buoyancy for Cerebral vessels

Choroid Plexus

Contained in all the ventricles, but minimally in occipital and frontal horn

Extracellular fluid in the blood stream passes through what

specialized cells (EPENDYMAL) cell lining and becomes CSF.

FLOW OF CEREBRAL SPINAL FLUID

Made in the ventricles —→ exits the ventricles by aperture in 4th ventricle —-→ to the cisterns—→ around the brain and SC ——→ reabsorbed in the arachnoid matter

Process and product are considered what kind of process

dependent secretory process

CSF is formed at a rate of

0.5ml/min.

Intracranial pressure (ICP)

due to bleeding or fluid in the ventricular system.

treatment for intracranial pressure

intracranial pressure monitor

what is normal cranial pressure

less than 100 ml of h2o

how is ICP determined

by volume of brain tissue, blood.

Increase in any area will first cause

compensation then increased ICP.

HYDROCEPHALUS

: Dilation of one or more parts of the ventricular system( abnormal collection of fluid).

Obstructive

Restriction of CSF flow within the ventricles proximal to the obstruction. Congenital

Communicating:

disruption of the flow after CSF has exited the ventricular system within the cisterna pathways . Hemorrhage or Infection