Ventricles & CSF Route

Ventricles

Cavities/Spaces within the brain

Ventricles contain _______ which is produced by a vascular structure ______ which lies inside the ventricles

Ventricles contain cerebrospinal fluid (CSF) which is produced by a vascular structure choroid plexus which lies inside the ventricles

How many of the ventricles are bilateral

1 bilateral

The rest = singular

What is the progression from neural tube to ventricles

Neural Tube → 3 primary brain vesicles → 5 secondary brain vesicles → Cavities develop into ventricles

Name the 3 primary brain vesicles

Which of the 3 primary brain vesicles develop into which of the 5 secondary brain vesicles

Mesencephalon stays as Mesencephalon!

(the 3 M vesicles go in alphabetical order!)

What adult brain structures & neural canal regions develop from the 5 secondary brain vesicles

IMPORTANT! [For each ventricle what brain area is it associated with (cerebrum, diencephalon, midbrain?)]

Ventricles are lined by ______ which specialise to form ______

Ventricles are lined by ependymal cells which specialise to form choroid plexus

Choroid plexus receives an arterial blood supply from what

choroidal arteries

Location of lateral ventricles

Paired spaces, one in each hemisphere

Extend through each lobe of the cerebrum

What ventricle are the lateral ventricles linked to & by what

Linked to the third ventricle by the interventricular foramina (2)

Location of third ventricle

A single unpaired midline space in the diencephalon

Location of the cerebral aqueduct

A narrow canal through the midbrain of the brainstem

Location of the fourth ventricle

A singular space posterior to the brainstem and anterior to the cerebellum

Route of CSF along ventricles

Lateral Ventricles → Interventricular Foramina (aka foramina of Monro) → Third Ventricle → Cerebral Aqueduct → Fourth Ventricle → Exits the ventricular system

What 2 routes does CSF take when it exits the ventricular system

It goes from the fourth ventricle either….

1. Through the median aperture → to the central canal of the spinal cord

   or…

2. Through the lateral apertures → to the cisterns in the subarachnoid space (between the meninges) → to the arachnoid villi/granules → to the venous sinus

Three core locations of choroid plexus (be specific - roof/floor)

Floor of the lateral ventricle

Roof of the third ventricle

Roof of the fourth ventricle

What is the problem in hydrocephalus

Overproduction of CSF, failure to drain or obstruction of flow

What happens as a result of hydrocephalus

Dilates the ventricles

Separates the calvaria in infants

What causes hydrocephalus

Congenital abnormalities

Head injury

Meningitis

Episodes of bleeding into the brain (rupture of pia)

Can you name the three main locations of formation of CSF precisely

Choroid plexus of the lateral ventricles

Choroid plexus of the third ventricle

Choroid plexus of the fourth ventricle

Don’t bother with 1, 10, 12, 13, 21, 22, 23, 25, 33