Cranial Cavity Flashcards
Function of dural folds
They help stabilize the brain within the cranial cavity during movements of the head
Describe attachments of falx cerebri & inclusded sinuses
Apex, attached to crista galli & frontal crest
Base to tentorium cerebelli lodging straight sinus
Upper border to sagittal sulcus lodging SSS
Lower border encloses ISS
Describe attachments of falx cerebelli and included sinuses
Apex: attached to margin of foramen magnus
Base: attached to tentorium cerebelli
Posteriorly: attached to internal occipital crest encosing occipital sulcus
Anterior free border
Tentorium cereblli forms roof of ……
Posterior cranial fossa
Describe attachments of tentorium cerebelli
Attached to lips of transverse sulcus + posterior clinoid process
Free border forming U-shaped tentorial notch between anterior clinoid processes for passage of midbrain
As regards the tentorium, at the point of cross of its two margins…..is related, & ……is ant to point of crossing.
4th CN
3rd CN
Diaphragma sellae has opening for passage of…..
Infundibulum of pituitary gland
Describe blood supply of dura
Ant cranial fossa: ant & posterior ethmoidal arts + middle meningeal artery
Middle cranial fossa: middle & accessory meningeak + ascending pharyngeal
Posterior cranial fossa: meningeal branches of vertebral, occipital & ascending pharyngeal arts
Describe nerve supply of dura
ACF: ethmoidal mainly, maxillary partly
MCF: maxillary ant 1/2, mandibular post 1/2
PCF meningeal branches of 10th & 12th ns + recurrent branches of C1,2,3
The recurrent tentorial branch supplies the tentorium cerebelli
Dura is drained by….&…..
Meningeal veins drain into dural sinuses
Diploic veins
Mention 2 possible results of skull trauma
Extradural: arterial mainly middle meningeal art causes cerebral compression, less common
Subdural: venous, cerebral compression & RBC in CSF, more common
Mention multiple sinuses of the dura
- Intercavernous (ant,middle &post): connect two cavernous sinuses
- Basilar plexus of veins: connect 2 inf petrosal sinus
SSS begins at…..&end at….to continue as….
Crista galli
Internal occipital protuberance
Right transverse sinus
…..veins drain into SSS
Superior cerebral
Mention factors that control passage of blood outside cavernous sinuses
Pulsactions of ICA
Gravity
Position of head
Describe external relations of caverbous sinus
Ant: superior orbital fissure & apex of orbit
Post: apex of petrous temporal bone & crus cerebri of midbrain
Lat: temporl lobe
Med: pituitary gland & sphenoid air sinus
Sup: optic tarct & ICA
Inf: foramen lacerum
Mention structures in lateral wall of cavernous sinus
Oculomotor (divides into its two divisions anteriorly, trochlear, ophthalmic (divides into its 3 divisions anteriorly), maxillary nerve (passes through foramen rotundum)
Mention structures passing through carverous sinus
ICA with its sympathetic plexus & abducent nerve (inferoletral to the artery)
Describe resukt of fracture of anterior cranial fossa
- Bleeding and CSF discharge through nose (cerebrospinal rhinorrhea)
- Hemorrhage into orbital cavity & beneath conjunctiva (Black eye)
Mention contents of superior obital fissue from lateral to medial
Lacrimal, frontal, trochlear (oustside tendinous arch)
Superior division of oculomotor, nasocilliray, inferior division of oculomotor, abducent (inside tendinous arch)
Mention structures passing in foramen ovale
Mandibular nerve, motor division of V, accessory meningeal art, lesser petrosal nerve, emissary vein
Mention structures passing in foramen spinosum
- Middle meningeal artery
- Meningeal branch of mandibular
GR: the middle Cranial fossa is the weakest part
Due to many foramina it contains, sphenoid air sinus & middle ear cavity.
What happens in case of middle cranial fossa fracture?
Bleeding & discharge CSF from ear
VI & VII CN are involved
Mention the largest & deepest cranial fossa
Posterior
Mention structures passing jugular foramen
- Inferior petrosal sinus (anteromedial)
- IJV (posterolateral)
- 9th, 10th, 11th CNs (intermediate compartment)
What happens in case of posterior cranial fossa fracture?
Bleeding into pharynx
Blood escapes into nape of the neck & collects in posterior triangle of neck
Mention tributaries of cavernous sinus
From orbit: sup & inf ophthalmic veins & central retinal
From brain: superficial middle cerebral vein, inf cerebral veins from temporal lobe
From meninges: sphenoparietal sinus & forntal trunk of middle meningeal vein
Desceibe drainage if cavernous sinus
Sup petrosal sinus to tranverse sinus
Inf petrosal sinus to IJV
Describe communications of cavernous sinsus
Pterygoid plexus via emissary veins
Facial v via sup opthalamic vein
The other sinus via 3 intercavernous sinuses
Thrombosis of cavernous sinus affects …..CNs
III, IV, VI
Carotid-cavernous sinus fistula leads to….
Uniltaeral pulsating exophthalmos
Inferior sagittal sinus is joined with……
Great cerebral vein
Stright sinus continues as…..
Transverse sinus unites with……to form….
Left transverse sinus
Suoerior petrosal sinus
Sigmoid sinus
Mention emissary veins connected to superior sagittal sinus
With scalp through parietal foramen
With nasal veinsthrough foramen caecum
Mention emissary veins connected to cavernous sinus
With pterygoid plexus, internal jugular vein (via inferior petrosal sinus) & facial vein
Mention emissary veins connected to simoid sinus
With internal jugular vein, occipital vein & suboccipital plexus
The trigeminal ganglion occupies a space of dura called…..
Cavum trigeminale
Middle meningeal art passes between roots of…..&grooves……
Auriculotemporal
Squamous part of temporal bone
Describe the supply given by middle meningeal arteries
Small branches to dura mater it is predominantly a periosteal artery supplying skull bones. It doesn’t supply brain or piaor anachnoid
……is the thinnest part of the skull & is liable to fracture
Pterion
Motor root of V passes through….to join….in
Foramen ovale
Mandibular nerve
Infratemporal fossa
Accessory minenigeal aretry passes through….
Foramen ovale
GR: Contralateral hemiplegia results from middle m.a. tear
As the frontal branch is commonly involved resulting in pressure on motor area
Regarding middle meningeal vein, the frontal trunk ends in …..while parietal ends in….
Pterygoid venous plexus or sphenoparietal or cavernous sinus
Pterygoid v.p.
Enumerate parts of ICA
Cervical, pertrous, cavernous & cerebral parts
The ICA terminates as…..
Ant & middle meningeal arts
Enumerate branches of petrous part of ICA
Corticotympanic & pterygoid branches
Enumerate branches of cavernous part of ICA
Branches to trigerminal ganglion
Hypophyseal branch
Meningesl branch to ant cranial fossa
Enumerate branches of cerebral part of ICA
Opthalmic, posterior communicating, ant choroidal & terminal branches.
