U9 Flashcards
What are the main protective structures of the CNS?
Cranium, meninges, cerebrospinal fluid (CSF), and the blood-brain barrier.
What are the three fossae in the cranial cavity?
Anterior, middle, and posterior fossae.
What is the innermost layer of the meninges?
Pia mater.
What is the outermost layer of the meninges?
Dura mater.
What is the arachnoid membrane?
A soft, spongey layer with arachnoid trabeculae.
What is the function of cerebrospinal fluid (CSF)?
Acts as a shock-absorber for the brain and spinal cord.
Where is CSF produced?
In the choroid plexus of all four ventricles.
What is obstructive hydrocephalus?
Blockage of CSF flow causing increased pressure in the ventricles.
How is obstructive hydrocephalus treated?
By inserting a shunt to drain excess CSF into the abdomen.
What is the superior sagittal sinus?
A dural venous sinus that drains CSF into the venous blood supply.
What is the role of the dural venous sinuses?
Draining venous blood and old CSF from the brain.
What are the two main types of strokes?
Haemorrhagic and ischemic strokes.
What causes a haemorrhagic stroke?
Bleeding in the brain from a burst blood vessel.
What causes an ischemic stroke?
Blocked blood flow due to a clot or embolus.
What is the blood-brain barrier?
A selective barrier that prevents harmful substances from entering the CNS.
What is the area postrema?
A brain region that detects toxins and triggers vomiting.
What is the dura mater composed of?
A tough, durable fibrous membrane.
What are arachnoid granulations?
Structures that reabsorb CSF into the venous blood.
What is a subdural haematoma?
Bleeding in the space between the dura mater and arachnoid.
What is an extradural/epidural haematoma?
Bleeding between the dura mater and the cranium.
What is the primary function of the cranium?
To provide support and protection for the brain.
What is meningitis?
Inflammation of the meninges caused by infection.
What is the flow of CSF in the ventricular system?
From lateral ventricles to the third, through the cerebral aqueduct to the fourth ventricle, and into the subarachnoid space.
What is the role of the falx cerebri?
Separates the cerebral hemispheres within the dura mater.
What is the role of the tentorium cerebelli?
Separates the cerebellum from the cerebral hemispheres.
What are the two main arteries supplying the brain?
Internal carotid arteries and vertebral arteries.
What happens if the brain’s blood supply is disrupted for a few minutes?
Permanent damage occurs.
How does the blood-brain barrier function?
It uses transporter proteins to control substance flow into the CNS.
Why is the brain’s blood supply constant?
To maintain oxygenation and prevent neuronal damage.
What is the composition of CSF?
A clear fluid that cushions the brain and spinal cord.
