Basic anatomy Flashcards
Skull is made up of what 2 components
Neurocranium + viscerocranium
How many bones make up neurocranium + what are they
8: 2 parietal 2 temporal 1 frontal 1 occipital 1 sphenoid 1 ethmoid
How many bones make up viscerocranium + what are they
14: 2 inferior nasal concha 2 lacrimal 2 maxilla 2 palatine 2 zygomatic 2 nasal 1 mandible 1 vomer
SCALP layers
Skin Connective tissue - dense Aponeurosis of epicranium Loose connective tissue Pericranium (periosteum of skull)
Why do wounds to scalp bleed profusely
Connective tissue in 2nd layer of scalp prevents vasoconstriction
What are emissary veins
Valveless veins that connect outer scalp to inside of cranial cavity, by traversing the dipole (spongy bone between outer and inner compact skull bone)
Muscles of facial expression (4)
Orbicularis oculi
Orbicularis oris
Buccinator
Occipitofrontalis
Structures that pass through parotid gland (3)
ECA
Retromandibular vein
Facial nerve
Sensory innervation to face + anterior scalp
CN V - trigeminal
Branches of trigeminal
Ophthalmic - V1
Maxillary - V2
Mandibular - V3
Nerve supply of muscles of mastication
CN V
Innervation of muscles of facial expression
CN VII - facial
What fibres does the facial nerve contain
Motor, special sensory + parasympathetic
How are cranial nerves different to spinal nerves
Spinal nerves carry SENSORY, MOTOR + SYMPATHETIC FIBRES
Cranial nerves carry EITHER SENSORY OR MOTOR OR PARASYMPATHETIC FIBRES OR COMBO
2 types of sensory fibres carried by cranial nerves
General sensory - touch, temp
Special sensory - vision, hearing, taste
What fibres does the optic nerve carry
Sensory only
What fibres does CN V carry (2) + what fibres do the branches specifically carry
Mainly general sensory, some motor
V1 - sensory
V2 - sensory
V3 - sensory + motor
So where does head and neck get sympathetic supply if cranial nerves don’t carry sympathetic fibres
Post ganglionic fibres from sympathetic chain form a plexus and travel along blood vessels in the head and neck
What are the right and left CCAs branches of
Right CCA - branch of brachiocephalic a
Left CCA - branch of aortic arch
Where do both CCAs bifurcate + what do they split into
C4
External and internal carotid artery
Which CCA branch has branches in the neck
ECA
What does ICA supply if It doesn’t branch in the neck
Goes into cranial cavity and supples that
What valveless veins drain the cranial cavity
Intracranial/ dural venous sinuses
What do intracranial/dural venous sinuses ultimately drain into
IJV
What vein drains regions outside cranial cavity
EJV