Skull and cranial cavity Flashcards
Outline the acronym scalp and the innervation to the scalp
S- skin C- connective tissue A- aponeurotic layer L- loose connective tissue P- pericranium
innervation to the scalp is from the trigeminal nerve (5th) and spinal cutaneous nerves and the scalp extends over the neurocranium
Outline the different parts of the skull
The skull is comprised of the neurocranium (8 bones) and the viscerocranium (14 bones)
What bones comprise the neurocranium
8 bones- occipital, 2 temporal, 2 parietal, sphenoid, ethmoid and frontal
What bones comprise the viscerocranium
14 bones- 2 nasal conchae, 2 nasal bones, 2 maxilla, 2 palatine bones, 2 zygomatic bones, 2 lacrimal bones, vomer and mandible
What is a foramina
An opening that allows for nerves, veins to leave the skull and for arteries to enter.
What does the cribiform plate foramina contain
CN 1
What does the optic canal foramina contain
CN2, Ophthalmic A
What does the superior orbital fissure foramina contain
CN 3,4,6,5 V1
What does the rotundum foramina contain
CN5, V2
What does the ovale foramina contain
CN5, V3, AMMA
What does the lacerum foramina contain
carotic artery*
What does the internal acoustic meatus foramina contain
CN7 and 8
What does the jugular foramen contain
CN 9, 10, 11, IJV
What does the hypoglossal canal foramina contain
CN12
What does the magnum foramina contain
Spinal cord
What are the 3 layers of the meninges of the skull
Dura mater (has 2 layers) , arachnoid mater and pia mater
What are the role of the meninges
protection, support network of blood vessels, form a fluid-filled cavity to cusion and nourish the brain.
What are the two layers of the dura mater
The endosteal layer- completely stuck to the skull
the meningeal layer- goes around brain and spinal cord.
the two layers form a dural sinus
What is the nerve and blood supply to the dura mater
CN 5, 10, C1-3 and sympathetic
blood supply- middle meningeal artery
Outline the arachnoid mater
Thin avascular layer between pia and dura
and it is a loose layer with projections and all structures passing to and from the brain must pass through the subarachnoid space.
Outline the pia mater
very delicate vascular membrane,
How do the dural coverings continue down to the spinal cord
The dural mater only has the meningeal part and still has the arachnoid mater and pia mater
What is leptomeningitis
an infection and inflammation in the arachnoid and pia mater, it may enter the subarachnoid space and enters the blood and cause septicaemia.
What are dural sinuses
created by the two layers of the dural mater and they become blood channels and they recieve excess csf which is picked up from arachnoid granulations. All the sinuses drain into the sigmoid sinus which then drains into the jugular vein
Outline the blood supply to the brain
The brain is supplied by the internal carotid artery and the vertebral artery. Inside the skull there are 2 main branches: anterior cerebral and middle cerebral artery
What is the circle and willis and how is it formed
Formed by an anastamosis between 2 internal carotid arteries and 2 vertebral arteries
What part of the brain does the anterior/middle/posterior cerebral artery
supplies the medial and superior surfaces of the brain and frontal lobe, lateral surfaces and temporal lobe, inferior surfaces and occipital lobe
