Flashcards in Cranium, meninges and brain Deck (59):
How many bones make up the skull?
Recall the 9 main bones of the skull
What bone forms the roof of the mouth?
What bone is seen to split the 2 halves of the nose?
What foramina are found in the maxilla?
Recall the 3 main sutures of the skull
What name is given to the protrusion at the most dorsal point of the occipital bone?
Inion (external occipital protuberance)
What name is given to the "soft spots" in the infant skull?
What is the internal capsule?
Fibrous tract where fibres from the cortex come together
Recall the layers of the scalp, from superficial to deep
Loose areolar tissue
Within which layer of the scalp are arteries, veins and nerves found?
Which muscle's aponeurosis forms the aponeurotic layer of the scalp?
Occipital and frontal bellies of the occipitofrontalis muscle
Which layer of the scalp facilitates movement?
Loose areolar tissue
Recall the fossae of the skull
Anterior, middle and posterior cranial; cerebellar
Recall the structures that pass through the foramen magnum
Meninges (these surround medulla)
Vertebral and spinal arteries (brain needs blood supply)
Dural veins (brain needs draining)
Which cranial fossa is the most shallow?
Recall the borders of each cranial fossa
Anterior = frontal bone to body and lesser wings of sphenoid
Middle = to dorsum sellae of sphenoid
Posterior = to internal occipital proturberance
Recall the relative positioning of the wings of the sphenoid bone
Lesser wing = anterior
2 lateral greater wings of sphenoid
What lies posteriorly to the hypophysial fossa?
Recall the foramina of the sphenoid bone, from anterior to posterior
Recall the positioning of the sphenoid sinuses
There are 2: one anterior to and one posterior to the sphenoid body
Recall the layers of the meninges from superficial to deep
Dura mater, arachnoid mater, pia mater
Where do emissory veins run?
Originate in superficial fascia, drain into diploic vein within bone of skull
Where does the cerebral vein run in relation to the meninges?
Deep to all of them
Where is the subarachnoid space?
Between arachnoid mater and pia mater
Describe the structure and structural properties of the dura mater
Thich and inelastic
Periosteal and meningeal layer
Describe the structure and structural properties of the arachnoid mater
Describe the structural properties of the pia mater
Thin and delicate
Which meningeal space is very large in the spine?
What is the falx cerebri?
Fold of meningeal layer of dura mater that runs into the longitudinal fissure
What is located at the base of the falx cerebri?
Inferior saggital sinus
Where is CSF produced and where is this located?
Choroid plexus = superior part of inferior horn of lateral ventricle
Recall the flow of CF from its production to its drainage
Lateral ventricle (choroid plexus)
arachnoid granulation villi = drainage --> superior saggital sinus
Why is an epidural bleed more dangerous in the skull than the spine?
Very small epidural space in brain so bleed is dangerous whereas in spine epidural space is large - ammeanable to CSF removal
What is the tenorium cerebelli and what is its function?
Extension of the dura mater that separates the cerebellum from the inferior part of the occipital lobes
Recall the foramina through which each of the cranial nerves enter
CNI = cribiform plate of ethmoid
CNII = optic canal
CNIII = superior orbital fissure
CNIV = superior orbital fissure
CNV1 = superior orbital fissure
CNV2 = foramen rotundum
CNV3 = foramen ovale
CNVI = superior orbital fissure
CNVII = internal acoustic meatus
CNVIII = internal acoustic meatus
CNIX = jugular foramen
CNX = jugular foramen
CNXI = jugular foramen
CNXI spinal roots = foramen magnum
CNXII = hypoglossal canal
Recall the vascular components that enter the skull via the optic canal
Central artery of retina
Recall the vascular components that enter the skull via the superior orbital fissure
Superior ophthalmic vein
Recall the path of the internal carotid artery entering the skull
Enters via the carotid canal, turns a right angle and runs just posterior to foramen lacerum
Recall the vascular components that enter the skull via the foramen spinosum
Middle meningeal artery and vein
Recall the vascular components that enter the skull via the internal acoustic meatus
Through which foramen of the skull does the sigmoid sinus drain into the internal jugular vein?
Recall the components of the Circle of Willis, from anterior to posterior
2 x Anterior cerebral
(connected by 2 x anterior communicating)
Joins: Bilateral internal carotids (medial) and middle cerebrals (lateral)
Posterior communicating arteries join them to the posterior cerebral
Anterior inferior cerebellar
Posterior inferior cerebellar
What is the main danger of a cavernous sinus thrombosis?
Disruption of cranial nerve travelling through
From which sinus does the great cerebral vein form?
Name the sinus branches that travel around the sides of the brain
Which sinus encircles the IJV?
What do the transverse sinuses converge to form?
Why do scalp lacerations threaten the brain
Emissory veins provide a route of transmission of infection since they drain into deeper veins
Where is the pterion and why is it clinically significant?
Where temporal, frontal, occipital and parietal bones meet
Thin part of skull
MMA runs just below = very vulnerable to extradural bleed
Recall the names of the cranial nerves
Describe the course of the facial nerve as it exits the skull
Exits skull via internal acoustic meatus and then stylomastoid foramen
Runs over parotid gland
Branches into 5 nerves supplying the face
Where is the primary motor cortex located?
Where is the primary somatosensory cortex located?
Recall the function of Wernicke's area
Sensory - speech
Recall the function of Broca's area
Motor - speech
Where are the colliculi seen on the brainstem?
Posteriorly, either side of pineal gland, on top of tectum
Posteriorly, what is seen in the centre of the pons?