Neuroanatomy part 2

Question 1

What are meninges?

Answer 1

They are three concentric coverings that encase the
central nervous system and act to support and stabilise the brain
and spinal cord.

Question 2

Name the three meninges from the outermost to the innermost layer

Answer 2

Dura matter
Arachnoid matter
Pia matter

Question 3

What are the two layers of the dura matter?

Answer 3

Periosteal layer - in relation to the skull (adherent to it)
Meningeal layer - In relation to the arachnoid layer (Superior to it)

Question 4

What are dural venous sinuses and where are they located?

Answer 4

Dural venous sinuses are venous drainage channels in between the two layers of the dura matter. They receive venous drainage from the cerebral cortex
-blood from the cortical veins drain blood into the venous sinuses

Question 5

Name the three venous sinuses

Answer 5

Superior sagittal sinus
Inferior sagittal sinus
Straight sinus

Question 6

Name the three septa or folds formed by the dura matter

Answer 6

falx cerebri which are present between the cerebral hemispheres,
* falx cerebelli which are present between the cerebellar hemispheres
* tentorium cerebelli which lies between the cerebrum and cerebellum

Question 7

Describe the arachnoid mater

Answer 7

It lies adjacent to the dura mater
It has several layer of flattened cells
Has arachnoid trabeculae (Strands of connective tissue that go all the way to the pia mater

Question 8

Describe the pia mater

Answer 8

Thin layer that is directly adherent to the brain
Follows the sulci and gyri of the brain
Highly vascularised

Question 9

Which meningeal layer is avascular and has no innervation

Answer 9

Arachnoid mater

Question 10

What is the space between the periosteal dura mater and the skull?

Answer 10

Epidural space

Question 11

What is the space between the meningeal dura mater and the arachnoid mater?

Answer 11

Subdural space

Question 12

What is the space between the arachnoid space and the pia mater?

Answer 12

subarachnoid space

Question 13

Which space has cerebrospinal fluid?

Answer 13

Subarachnoid space

Question 14

Unpaired sinus that is located in the superior margin of the falx cerebri, that drains blood from the lateral aspects of anterior cerebral hemispheres into the confluence of sinuses.

What is this sinus?

Answer 14

Superior sagittal sinus

Question 15

Unpaired sinus located in the inferior margin of the falx cerebri.
What is this sinus, and which parts of the brain does it drain?

Answer 15

Inferior sagittal sinus.
Drains blood from the medial aspects of the cerebral hemisphere into the straight sinus

Question 16

What does the straight sinus drain?

Answer 16

Receives blood from the inferior sagittal sinus and the cerebellum and
drains into the confluence

Question 17

Describe the confluence

Answer 17

Formed by the merger of the superior sagittal sinus and the straight sinus
Drains blood into the transverse sinuses.

Question 18

Which sinus drains blood from the confluence to the sigmoid sinus?

Answer 18

Transverse sinus

Question 19

how many pairs of spinal nerves do we have? How many nerves in each vertebral level?

Answer 19

31 pairs
8 Cervical
* 12 Thoracic
* 5 Lumbar
* 5 Sacral
* 1 Coccygeal

Question 20

True or false: Spinal nerves contain motor fibers only

Answer 20

False, spinal nerves have both sensory and motor fibers

Question 21

Which fibers are found in the dorsal root and which fibers are found in the ventral root?

Answer 21

Dorsal root: sensory fibers from sensory neurons in the dorsal root ganglia, from the dorsal horn of the spinal cord
Ventral root: motor fibers of motor neurons from the ventral horn of the spinal cord

Question 22

how does the mixed spinal nerve branch out

Answer 22

Dorsal and ventral ramus

Question 23

True or false: the dorsal ramus of the spinal nerve only has sensory fibres.

Answer 23

False: The rami of the spinal nerve are formed once the nerve has been formed. Therefore it has both sensory and motor fibers.

Question 24

What layers continue with spinal cord

Answer 24

Dura mater and meningeal layer

Question 25

Which part of medulla oblongata continues in spinal cord

Answer 25

Anterior median fissure

Question 26

What shows anteriorly on spinal cord

Answer 26

Anterior median fissure

Question 27

What shows posterioly on spinal cord

Answer 27

(depression)
Posterior median sulcus

Question 28

What is found at the anterior and posterior corresponding cord segments

Answer 28

Series of rootlets

Question 29

What is found internally on the spinal cord

Answer 29

H-shaped gray matter
White matter

Question 30

What does grey matter of spinal cord consist of

Answer 30

cell bodies of neurons

Question 31

What does white matter of spinal cord consist of

Answer 31

myelinated axons

Question 32

Horns of grey matter of spinal cord

Answer 32

Ventral- has motor neurons

Dorsal- has cell bodies that receive sensory info

Question 33

Where are the sensory fibres on the dorsal root from

Answer 33

Dorsal root ganglia

Question 34

What to remember about spinal nerves

Answer 34

Rami are after spinal nerve has been formed
Therefore, ramus would have mixed fibres
However, roots are before nerve has formed
Thus have specifically either motor or sensory fibres