Intracranial Space Occupying Lesions and Head Trauma Flashcards
What are space occupying lesions?
Abnormal tissue taking up space.
Increased ICP may result in contents doing what?
Herniating.
What are the 5 layers of the scalp?
S - skin. C - connective tissue. A - aponeurosis. L - loose connective tissue. P - pericranium.
The scalp arteries form what?
A rich anastomotic network just deep to the skin.
As the scalp arteries form a rich anastomotic network, scalp lacerations and incisions are prone to what?
Bleeding excessively.
The right ophthalmic artery is a branch of what?
Right internal carotid artery.
What is the function of sutures (fibrous joints) of the skull?
Help to prevent skull fractures from spreading and thus minimise propagation.
Describe the pterion.
- H-shaped.
- Made up of frontal, parietal, temporal and sphenoid bones.
- Thinnest part of skull.
Describe the relationship between the middle meningeal artery and the pterion.
The middle meningeal artery courses over the deep aspect of the pterion.
The groove across the deep surface of the pterion is made by what?
The R/L middle meningeal artery.
The groove between the deep surfaces of the temporal and occipital bones are made by what?
The R/L sigmoid sinus.
What is meningitis?
Usually a bacterial or viral infection of the meninges.
What are the meninges?
Protective coverings for the brain and spinal cord.
The brain and spinal cord are surrounded by how many layers of membrane?
Three.
Name the three layers of membrane surrounding the brain and spinal cord.
- Dura mater.
- Arachnoid mater.
- Pia mater.
Describe dura mater.
“hard mother”.
- Tough/fibrous layer receiving sensory supply from mainly CN V.
- Encloses the dural venous sinuses.
Where are the dural venous sinuses enclosed?
Within the dura mater.
What does the arachnoid mater contain and what are their functions?
Arachnoid granulations that contain the circulating CSF.
Describe pia mater.
Adherent to the brain, the blood vessels and nerves entering/exiting the brain.
What is responsible for pain in meningitis?
Stretching of dura mater.
Dura mater is adherent to what?
Internal aspect of all bones of the skull.
What is diaphragm sellae?
A tough sheet of dura mater forming a roof over the pituitary fossa.
What is tentorium cerebelli?
Tough sheet of dura mater “tenting” over the cerebellum, attaching to the ridge of the petrous temporal bones with a central gap to permit the brainstem to exit.
What is falx cerebri?
Midline structure made of dura mater attaching to the deep aspect of the skull and separating the right and left cerebral hemispheres.
What does falx cerebri attach to anteriorly?
Crista galli of the ethmoid bone.
What does falx cerebri attach to posteriorly?
Internal occipital protruberance of the occipital bone.
Falx cerebri separates what?
The right and left cerebral hemispheres.
Cerebral veins drain venous blood from the brain into what?
Dural venous sinuses.