Scalp and Cranial Cavity Flashcards
what are the 5 layers of the scalp
skin, dense connective tissue, epicranial aponeurosis, loose connective tissue, pericranium
what are the first 3 layers of the scalp and what are they known as collectively
skin, dense connective tissue, epicranial aponeurosis - scalp proper
what does the skin layer contain
hair follicles, sweat, sebaceous glands
what is the dense connective tissue
subcutaneous layer richly vascularised with cutaneous nerves
what is the epicranial aponeurosis
tendon and muscle of occipitofrontalis
what is the loose connective tissue
loose areolar tissue containing spaces susceptible to fluid/infection spread
what is the pericranium
external periosteum of skull
where are the spaces for potential accumulation of fluid/spread of infection
between aponeurosis and pericranium
how can fluid/infection spread to the eyelids or root of nose
frontal belly of occipitofrontalis inserts into SKIN and SUBCUTANEOUS TISSUE not bone so there can be no trapping of infection frontally
how do scalp infections spread to the intracranial structures
via emissary veins
what is the sensory/cutaneous innervation of the face by
trigeminal nerve
what is the motor innervation of the face by
facial nerve
what is the posterior part of the head innervated by
cervical spinal nerves 2 and 3
what is the arterial blood supply to the scalp
internal and external carotid arteries
what are the branches of the internal carotid artery supplying the scalp
supraorbital and supratrochlear
what are the branches of the external carotid artery suppling the scalp
superficial temporal, posterior auricular, occipital
what is the posterior lymphatic drainage of the scalp
mastoid and occipital nodes drain to deep cervical nodes
what lymph nodes are present in the anterior scalp
pre-auricular and parotid nodes
what does everything in the scalp eventually drain to
internal jugular vein lymph nodes
what are the 3 cranial fossa
anterior, middle, posterior
what bones is the anterior cranial fossa made up of
frontal, ethmoid and sphenoid
what sits in the anterior cranial fossa
frontal lobes
what passes through the foramina of the cribriform plate
olfactory fibres
what are the frontal crest and the crista galli
attachment sites
what bones is the middle cranial fossa made up of
sphenoid and temporal bones
what occupies the middle cranial fossa
temporal lobes
where does the pituitary gland lie?
hypophyseal fossa (deepest part of sellae turcica)
what is the main landmark of the middle cranial fossa
the crescent of foramina
what foramina are present in the middle cranial fossa
superior orbital fissure, foramen rotundum, foramen ovale, foramen spinosum
what passes through the superior orbital fissure
CNIII, IV, V, VI
what passes through the foramen rotundum
CNV2
what passes through the foramen ovale
CNV3 and accessory meningeal artery
what passes through the foramen spinosum
middle meningeal artery and meningeal branch of mandibular nerve
what bones make up the posterior cranial fossa
sphenoid, occipital and temporal bones
what occupies the posterior cranial fossa
cerebellum and brainstem
what is the clivus
where the brainstem enters the foramen magnum
what is the jugular foramen for
jugular vein and cranial nerves to exit (also for some dural infolds to drain into venous structures)
what are buttresses
thicker portions of cranial bone that transmit forces around weaker regions of the cranium
what are cranial meninges
membranous layers that help in protection of the brain
what are the 2 layers of the dura mater
periosteal layer (attached to bone) and meningeal layer (in contact with arachnoid mater)
what are the 2 layers of the dura mater separated by
venous sinuses and dural folds
where is the arachnoid mater
lines the dura mater but not attached
what are the 3 types of mater
dura, arachnoid, pia
what is the subarachnoid space
space below arachnoid mater filled with fluid (CSF)
what drains the CSF from the subarachnoid space
arachnoid villi
what is a collection of arachnoid villi called
arachnoid granulation
where can arachnoid granulations be found
in the sagittal sinus and lateral lacunae
what is pia mater
thin membrane attached to surface of the brain
where does the pia mater go
enters the sulci of the brain and all of the fissures
what are the 4 dura mater folds
falx cerebri, tentorium cerebelli, falx cerebelli, diaphragma sellae
what do the dura folds do
limits the movement of the brain within the cavity so if there is trauma the brain doesn’t move
what is the blood supply of the dura mater
meningeal arteries (anterior, middle, accessory, posterior)
