Brain and Cranium

Question 0

Where is the coronal suture?

Answer 0

The coronal suture lies in the coronal plane between the unpaired frontal bone and the two parietal bones

Question 1

What is the calveria?

Answer 1

The calvaria is the upper domelike portion of the bony skull (the skullcap)

Question 2

Where is the sagittal suture?

Answer 2

The sagittal suture is on the top of the skull between the two parietal bones

Question 3

Where is the pterion?

Why is it a clinically important landmark?

Answer 3

The pterion is an “H”-shaped sutural junction located on the lateral aspect of the skull. It can be found at the junction of the greater wing of the sphenoid, the squamous temporal, the frontal, and the parietal bones. It is clinically important because it lies over the course of a large middle meningeal artery branch. Fractures across the pterion can lead to epidural hemtomas

Question 4

Where would one find the middle meningeal artery?

From what artery does it arise?

Answer 4

The middle meningeal artery arises from the maxillary artery and enters the cranial cavity through the foramen spinosum. Its branches travel between the inside of the skull bones and the dura mater.

Question 5

What type of hematoma typically results from tearing the middle meningeal artery?

Answer 5

Epidural Hematomas

Question 6

What cranial fossa contains the foramen magnum?

Answer 6

Posterior Cranial Fossa

Question 7

What cranial fossa contains the superior orbital fissure?

Answer 7

Middle Cranial Fossa

Question 8

What is the sella turcica?

What important glandular structure is associated with it?

Answer 8

The sella turcica is a saddle-like prominence on the upper surface of the sphenoid bone, situated in the middle cranial fossa and dividing it into two halves. It contains the pituitary gland.

Question 9

What is a gyrus?

What is a sulcus?

Answer 9

A gyrus is one of the prominent rounded elevations that form the cerebral hemispheres. The gyri are separated by sulci, which are the grooves or furrows on the surface of the cerebrum.

Question 10

Where is the pons located?

Answer 10

The pons is located on the ventral surface of the brainstem between the midbrain and the medulla oblongata, inferior to the cerebellum.

Question 11

Where is the medulla oblongata located?

Answer 11

The medulla oblongata is that portion of the brainstem between the pons and the spinal cord. It is continuous with the spinal cord at the foramen magnum.

Question 12

What is the falx cerebri?

Answer 12

The falx cerebri is the sickle-shaped fold of the dura mater in the longitudinal fissure between the two cerebral hemispheres.

Question 13

What would one find within the superior sagittal sinus?

Answer 13

The superior sagittal sinus contains venous blood. It also contains the arachnoid granulations, which protrude into the sinus from beneath as the CSF pressure rises.

Question 14

What is the predominant route by which cerebral blood drains from the cranial cavity?

Answer 14

The venous blood within the cranial cavity eventually collects in the larger cerebral veins which drain into one of several dural venous sinuses. The blood in the dural venous sinuses drains predominantly into the internal jugular vein.

Question 15

What are emissary veins?

Why are they clinically important structures?

Answer 15

Emissary veins are venous channels located between the venous sinuses of the dura mater and the veins of the diploe and the scalp. They are clinically important in that they provide a potential passage for the spread of infection between the scalp and the intracranial venous sinuses.

Question 16

Where is CSF produced?

Answer 16

CSF is produced within the ventricles of the brain by the choroid plexus

Question 17

What is the name of the structure that produces CSF?

Answer 17

Choroid plexus

Question 18

How does the CSF eventually drain into the venous system?

Answer 18

The main passageway of CSF drainage is through the arachnoid granulations and into the venous blood of the superior sagittal sinus

Question 19

What is hydrocephalus?

Answer 19

Hydrocephalus is any condition marked by an excessive accumulation of CSF within the cranial cavity. One common type of hydrocephalus, caused by a congenital blockage of the cerebral aqueduct, results in dilation of the cerebral ventricles, thinning of the brain tissues and separation of cranial bones

Question 20

Which two pairs of major arteries enter the cranial cavity to supple blood to the brain?

Answer 20

The internal carotid arteries and the vertebral arteries

Question 21

What is the major unpaired artery that is formed from the two vertebral arteries within the cranial cavity?

Answer 21

The basilar artery

Question 22

How do the anterior, middle and posterior cerebral arteries arise?

Answer 22

The internal carotid arteries terminate within the cranial cavity by dividing into the anterior and middle cerebral arteries. The single basilar artery ends by dividing into tow posterior cerebral arteries

Question 23

What is the circle of willis?

Answer 23

The circle of willis is an anastomotic circle of arteries (roughly pentagonal in outline) at the base of the brain, formed, sequentially (in anterior to posterior direction) by the anterior cerebral, the two internal carotid, the two posterior communicating, ,and the two posterior cerebral arteries

Question 24

How many pains of cranial nerves are there?

Answer 24

12 pairs

Question 25

What is the name of the 7th cranial nerve?

Answer 25

Facial Nerve

Question 26

What is the name of the 10th cranial nerve?

Answer 26

Vagus Nerve

Question 27

What is the cranial nerve number of the glossopharyngeal nerve?

Answer 27

CN IX

Question 28

Which cranial nerves travel through a foramen associated with the internal jugular vein?

Answer 28

CN IX, X, and XI travel through the jugular foramen

Question 29

Which cranial nerves travel through the cribriform plate openings?

Answer 29

CN I travels through the cribriform plate

Question 30

Which cranial nerves travel through the superior orbital fissure?

Answer 30

CN III, IV, V1, and VI

Question 31

In which cranial fossa is the internal auditory meatus located?

Which cranial nerves travel through it?

Answer 31

The internal auditory meatus, for CN VII and VIII, is in the posterior cranial fossa

Question 32

Which cranial nerve has a component that ravels through the foramen magnum?

Answer 32

CN XI (spinal accessory nerve) has a spinal root that travels through the foramen magnum

Question 33

How do postganglionic sympathetic nerves get into the cranial cavity?

Answer 33

Sympathetic nerves enter the cranial cavity in a plexus on the major arteries traveling from the neck into the cranial cavity - especially the internal carotid arteries

Question 34

What important glandular structure lies immediately inferior to the optic chiasm?

Answer 34

The pituitary gland lies immediately below the optic chiasm

Question 35

Which unique cranial nerve structure lies within the circle of willis?

Answer 35

The optic chiasm of CN II lies within the circle of willis

Question 36

Where is the cavernous sinus located?

Answer 36

The cavernous sinuses are located on either side of the sella turcica in the middle cranial fossae

Question 37

Which artery travels directly through the cavernous sinus?

Answer 37

The internal carotid arteries travel through the cavernous sinus.