Skull Flashcards
Synovial joints in head
3
Temporomandibular joint
Between three tiny bones in middle ear - malleus, incus and stapes
Cervical vertebrae characterized by
small body
bifid spinous process
foramen transversarium (allow vertebral artery and vein to pass through)
Hyoid bone
Superiorly, attached to floor of oral cavity
Inferiorly, attached to larynx
Posteriorly, attached to pharynx
Visible on greater wing of sphenoid bone on inferior view of skull
Foramen ovale
Foramen spinosum
Base of skull split into 3 parts
Anterior - teeth and hard palate
Middle - behind hard palate to anterior margin of foramen magnum
Posterior - anterior edge of foramen magnum to superior nuchal lines
Sphenoid bone
Greater wing
Lesser wing (not seen in inferior view)
Pterygoid process
Foramen lacerum
Petrous part of temporal bone
basilar part of occipital medially
body of sphenoid anteriorly
Temporal bone parts and processes
Squamous part
Petrous part
Mastoid part
Tympanic part
Zygomatic process
Styloid process
Carotid canal
Petrous part of temporal bone
Auditory tube
Between greater wing of sphenoid anteriorly and petrous part of temporal bone posteriorly
Parts of occipital bone
Squamous part (posterior to foramen magnum) Lateral part (lateral to foramen magnum) Basilar part (anterior to foramen magnum)
Jugular foramen is anterolateral hypoglossal canal
Anterior cranial fossa
Frontal ethmoid and sphenoid
Internal foramina of anterior cranial fossa
Foramen cecum
Olfactory foramen in cribriform plate
Foramen cecum
Emissary veins to nasal cavity
Middle cranial fossa
Part of sphenoid and temporal bones
Sella turcica
Remainder of body of sphenoid, consists of deep central area (hypophyseal fossa) which contains pituitary glands
Anteriorly - tuberculum sellae
Posteriorly - dorsum sellae
Internal foramina of middle cranial fossa
Optic canal Superior orbital fissure Foramen rotundum Foramen ovale Foramen spinosum Hiatus for greater petrosal nerve Hiatus for lesser petrosal nerve
Superior orbital fissure
Between greater and lesser wing of sphenoid bone
Major passageway between orbit and middle cranial fossa.
Contents of superior orbital fissure
Oculomotor nerve III Trochlear nerve IV Ophthalmic nerve V1 Abducens nerve VI Ophthalmic veins
Optic canal
Lesser wing of sphenoid bone
optic nerve and ophthalmic artery
Foramen rotundum
Greater wing of sphenoid bone
Maxillary nerve V2 - from middle cranial fossa to pterygopalatine fossa
Foramen ovale
Greater wing of sphenoid bone
Connects middle cranial fossa to infratemporal fossa
Mandibular nerve V3
Lesser petrosal nerve (from nerve IX)
Small vessel - accessory middle meningeal artery
Foramen spinosum
Greater wing of sphenoid bone
Connects middle cranial fossa to infratemporal fossa
Middle meningeal artery
Posterior cranial fossa
Mainly temporal and occipital bone
Some of sphenoid and parietal
Contain brainstem and cerebellum
Internal foramina in posterior cranial fossa
Foramen magnum Internal acoustic meatus Jugular foramen Hypoglossal canal Condylar canal
Foramen magnum
Spinal cord
Vertebral arteries
Meninges
Spinal roots of accessory nerve
Internal acoustic meatus
Petrous part of temporal bone
Nerve VII and VIII
Labyrinthine artery and vein
Jugular foramen
Separates petrous part of temporal bone and occpital bone
Groove to inferior petrosal sinus is medial to this
Groove to sigmoid sinus is lateral to this
Nerve 9 10 11
Sigmoid sinus
Passes into jugular foramen
Inferior petrosal sinus
empties into internal jugular vein in area of jugular foramen
Hypoglossal canal
In occipital bone
Nerve 12, maningeal branch of ascending pharyngeal artery
Arterial supply to dura mater
Travels in outer periosteal layer of dura mater
Anterior meningeal arteries
Middle and accessory arteries
Posterior meningeal arteries
Flow of CSF
Produced by choroid plexus
Flows from lateral ventricle to third ventricle via interventricular foramina (foramina of Monro)
Then to fourth ventricle via cerebral aqueduct (aqueduct of Sylvia)
Then from there passes into subarachnoid space via midline foramen or 2 lateral foramina (foramen of Magendie and Luschka)
Vertebral arteries
From first part of subclavian artery
branches before joining up to form basilar artery: anterior spinal artery, posterior spinal artery, posterior inferior cerebellar artery
Branches after joining to form basilar artery: anterior inferior cerebellar artery, pontine arteries, superior cerebellar artery
Basilar artery branches into 2 posterior cerebral arteries
Internal carotid artery branches
Ophthalmic artery
Posterior communicating artery (connects posterior ceberal and internal carotid artery)
Middle cerebral
Anterior cerebral
Tributaries into dural venous sinus
Emissary vein (from outside cranial cavity) Diploic vein (between internal and external tables of compact bone in roof of cranial cavity)
Dural venous vein drainage
into internal jugular vein
Dural venous sinus
Superior sagittal Inferior sagittal Straight Transverse Sigmoid (continuation of transverse to IJV) Occipital sinus Confluence of sinuses
Cavernous sinus
Sphenoparietal
Superior and inferior petrosal
Basilar sinus
Transverse sinus
Right - receives blood mainly from superior sagittal
Left - receives blood mainly from straight sinus
Cavernous sinus
Against lateral aspect of body of sphenoid on either side of sella turcica
Receives blood from cerebral + ophthalmic veins + emissary veins (from pterygoid plexus of veins in infratemporal fossa)
Structures in cavernous sinus
Internal carotid artery
Abducens nerve
Oculomotor
Trochlear
Ophthalmic
Maxillary
Superior petrosal sinus
Drain cavernous sinus into transverse sinus
Inferior petrosal sinus
Drain cavernous sinus into IJV
