NS-CRANIAL FORAMINA AND MENENGES

Question 1

What is found within the fossa at base of the skull which forms the floor of the cranial cavity?

Answer 1

Cranial foramen

Question 2

The floor of the cranial cavity id divided into 3 fossae:

Answer 2

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 )]

Question 3

how many cranial nerve do we have?

Answer 3

12 cranial nerves
only one of the two Athletes felt very good, victorious and happy.

Question 4

Anterior cranial fossa

Answer 4

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.

Question 5

The middle cranial fossa

Answer 5

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

Question 6

foramen rotundum and foramen ovale are found in which cranial fossa?

Answer 6

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.

Question 7

Posterior cranial fossa

Answer 7

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

Question 8

stabilize the shape and position of the central nervous system?

Answer 8

Meninges

Question 9

what covers the brain and the cranial fossa?

Answer 9

Meninges

Question 10

Name 3 layers of meninges?

Answer 10

.>Dura mater is the outermost layer
Outer periosteal layer
Inner meningeal layer

> Arachnoid mater is the intermediate layer

> Pia mater is the innermost layer

Question 11

Meninges that may also be referred to as Pachymeninx?

Answer 11

Dura mater

Question 12

Dura Mater

Answer 12

is the outermost of the 3-layer
strongest layer protecting the brain and spinal cord

double layer membrane.
> outer endosteal layer
> inner meningeal layer

Question 13

The outer endosteal layer of Dura mater?

Answer 13

serves as periosteum on the cranial inner surface.

its adheres tightly to the inner meningeal layer.

no clear boundary except the sinuses.

Question 14

There2 spaces that exist around the dura mater name those spaces?

Answer 14

1.Epidural space -
between cranium and the periosteal later/ outermost layer of dura mater

2. subdural space- between the inner dura mater and the arachnoid meingies

Question 15

Inner meningeal layer

Answer 15

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.

Question 16

Name 4 types of dural folds

Answer 16

> 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.

Question 17

superior sagittal sinus

Answer 17

Located on the attached edge of the falx cerebri.

Runs from the anterior to posterior (along the midsagittal plane)

Question 18

anterior what the sagittal sinus related to ?

Answer 18

Foramen caecum

then course along the attached edge of the falx cerebri.

Question 19

posterior the superior sagittal sinus drains to what ?

Answer 19

confluence sinus

Question 20

superior sagittal sinus drains what ?

Answer 20

drains veins that drains the brain and cerebrospinal fliud?

Question 21

what is located in the free edge of the falx cerebri

Answer 21

inferior sagittal sinus

Question 22

straight sinus

Answer 22

> 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.

Question 23

Confluence of Sinuses

Answer 23

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.

Question 24

Sinuses extend horizontally along the attached edge of tentorium cerebelli?

Answer 24

Transverse sinus
from posterior to anterior

Question 25

right transverse sinus usually drains what ?

Answer 25

the superior sagittal sinus

Question 26

Left transverse sinus usually drains

Answer 26

straight sinus

Question 27

Sinuses also receive blood

Answer 27

from the superior petrosal sinus

Question 28

transverse sinus Leaves the surface of the occipital bone to become the ?

Answer 28

sigmoid sinus

Question 29

sigmoid sinus

Answer 29

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

Question 30

Arachnoid mater?

Answer 30

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

Question 31

Pia Mater

Answer 31

Thin delicate layer that closely adheres to the brain surface
Enters grooves and fissures of the brain.

Question 32

meningeal innervation is mainly from the meningeal branches.?

Answer 32

of the both the trigeminal and vagus nerves

Question 33

Anterior cranial fossa

Answer 33

Ophthalmic division of the trigeminal nerve
Meningeal branches from the maxillary nerve (CN V2)
Middle cranial fossa

Question 34

Middle cranial fossa

Answer 34

Meningeal branches of ophthalmic, maxillary, and mandibular divisions of the trigeminal nerve

Question 35

Posterior cranial fossa

Answer 35

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.