NS-CRANIAL FORAMINA AND MENENGES Flashcards
What is found within the fossa at base of the skull which forms the floor of the cranial cavity?
Cranial foramen
The floor of the cranial cavity id divided into 3 fossae:
Anterior cranial fossa [ Frontal bone, ethmoid bone, sphenoid bone (Lesser wings and body)]
Middle cranial fossa [Temporal bone and sphenoid bone (Greater wings and sella turcica )]
Posterior cranial fossa [Temporal bones, occipital bones, with small contributions from the sphenoid and parietal bones )]
how many cranial nerve do we have?
12 cranial nerves
only one of the two Athletes felt very good, victorious and happy.
Anterior cranial fossa
made up of the frontal bone, sphenoid and ethmoid bone.
Consist of Olfactory foramina.
located at the cribriform plates of the ethmoid bone.
content: Cranial nerve 1- olfactory nerve.
The middle cranial fossa
Consist of :
Optical canal
Located on the sphenoid bone
Contents: CN II (Optic nerve) and Ophthalmic artery
Superior orbital fissure
Located between greater and lesser wings of the sphenoid bone
Contents: CN III (Oculomotor nerve); CN IV (Trochlear nerve); CN V1 (Ophthalmic division of the trigeminal nerve); CN VI abducent nerve; ophthalmic veins
foramen rotundum and foramen ovale are found in which cranial fossa?
in the middle cranial fossa.
Foramen rotundum
Located on the greater wings of the sphenoid bone.
Contents: CN V2 (Maxillary division of trigeminal
Foramen ovale
Located on the greater wings of the sphenoid bone
Contents: CN V3 (Mandibular division of the trigeminal nerve) and Accessory meningeal artery
Foramen spinosum
Located on the greater wings of the sphenoid bone
Contents: Middle meningeal artery and vein
Foramen lacerum
Located at the junction of temporal, sphenoid, and occipital bones
Contents: Deep petrosal nerve, internal carotid artery, and greater petrosal nerve.
Posterior cranial fossa
Internal acoustic meatus
Located on the greater wings of the sphenoid bone
Contents: CN VII ( Facial nerve) and CN VIII (Vestibulocochlear nerve)
Jugular foramen
Located at the junction of temporal and occipital bones
Contents: CN IX (Glossopharyngeal nerve), CN X (Vagus nerve) and CN XI ( Accessory nerve)
Hypoglossal canal
Located on the occipital bones
Contents: CN XII (Hypoglossal nerve)
Foramen magnum
Located on the occipital bones
Contents: CN XI (Accessory nerve), meninges, vertebral and spinal arteries, and medulla oblongata
stabilize the shape and position of the central nervous system?
Meninges
what covers the brain and the cranial fossa?
Meninges
Name 3 layers of meninges?
.>Dura mater is the outermost layer
Outer periosteal layer
Inner meningeal layer
> Arachnoid mater is the intermediate layer
> Pia mater is the innermost layer
Meninges that may also be referred to as Pachymeninx?
Dura mater
Dura Mater
is the outermost of the 3-layer
strongest layer protecting the brain and spinal cord
double layer membrane.
> outer endosteal layer
> inner meningeal layer
The outer endosteal layer of Dura mater?
serves as periosteum on the cranial inner surface.
its adheres tightly to the inner meningeal layer.
no clear boundary except the sinuses.
There2 spaces that exist around the dura mater name those spaces?
1.Epidural space -
between cranium and the periosteal later/ outermost layer of dura mater
- subdural space- between the inner dura mater and the arachnoid meingies
Inner meningeal layer
separate the periosteal layer and protrude into the cranial cavity.
Separation creates double-layered dural folds.
may also refer to them as dural reflections/septa.
Name 4 types of dural folds
> falx cerebri- sickle-shaped fold between cerebral hemispheres
> falx cerebelli- partially extends between cerebrallar hemispheres.
> Tentorium cerebelli- horizontal fold between the cerebrum and cerebellum.
Diaphragma sellae- ovaries pituitary fossa- allows infundibulum of the pituitary gland through.
superior sagittal sinus
Located on the attached edge of the falx cerebri.
Runs from the anterior to posterior (along the midsagittal plane)
anterior what the sagittal sinus related to ?
Foramen caecum
then course along the attached edge of the falx cerebri.
posterior the superior sagittal sinus drains to what ?
confluence sinus
superior sagittal sinus drains what ?
drains veins that drains the brain and cerebrospinal fliud?
what is located in the free edge of the falx cerebri
inferior sagittal sinus
straight sinus
> located at the junction of falx cerebri and tentorium cerebelli.
Drains the cerebral, great cerebral, superior cerebellar veins and the inferior sagittal sinus.
Drains into the confluence of sinuses.
Confluence of Sinuses
connecting point of the superior sagittal sinus, straight sinus sinus and occipital sinus
located near the internal occipital protuberance.
drains into the left and right transverse sinuses.
Sinuses extend horizontally along the attached edge of tentorium cerebelli?
Transverse sinus
from posterior to anterior
right transverse sinus usually drains what ?
the superior sagittal sinus
Left transverse sinus usually drains
straight sinus
Sinuses also receive blood
from the superior petrosal sinus
transverse sinus Leaves the surface of the occipital bone to become the ?
sigmoid sinus
sigmoid sinus
Descends within the posterior cranial fossa - Towards the jugular foramen
Sinus drains cerebral, cerebellar, diploic, and emissary veins
Sinus drains into the internal jugular vein
Arachnoid mater?
Avascular membrane that lines the meningeal layer of the dura mater
Thin process extend from it into the subarachnoid space
It is continuous with the pia mater
Lies over sulci and gyri
Does not lie within the sulci
Pia Mater
Thin delicate layer that closely adheres to the brain surface
Enters grooves and fissures of the brain.
meningeal innervation is mainly from the meningeal branches.?
of the both the trigeminal and vagus nerves
Anterior cranial fossa
Ophthalmic division of the trigeminal nerve
Meningeal branches from the maxillary nerve (CN V2)
Middle cranial fossa
Middle cranial fossa
Meningeal branches of ophthalmic, maxillary, and mandibular divisions of the trigeminal nerve
Posterior cranial fossa
Meningeal branches from the vagus nerve (CN X) and glossopharyngeal nerve (CN IX) supply the inferior surface of the tentorium and dura of the posterior fossa.
