Week 5

Question 1

What is the crista galli

Answer 1

bony projection which attaches to falx cerebri, front of middle cranial fossa

Question 2

what is the falx cerebri

Answer 2

large fold of dura mater in the midline of the head, very tough layer of dense irregular connective tissue.
Separates right and left hemispheres

Question 3

what is the tentorium cerebelli

Answer 3

fold of dura mater which covers cerebellum, almost horizontal fold. Separates back of cerebral hemispheres with the cerebellum underneath

Question 4

what do the large folds of dura mater and CSF allow

Answer 4

protects the brain by minimising movement

Question 5

what is the vessel which is in an endotheium lined channel in the attachment of the falx

Answer 5

superior sagittal sinus

Question 6

what are the walls of the superior sagittal sinus made of

Answer 6

dura

Question 7

what veins drain the upper part of the brain

Answer 7

superior cerebral veins

Question 8

do the superior cerebral veins have valves

Answer 8

no

Question 9

if the superior cerebral veins tear, what haemorrhage do they cause

Answer 9

subdural haemorrhage

Question 10

what does the great cerebral vein drain

Answer 10

the midline part of the forbrain (area of thalamus and hypothalamus

Question 11

where does the great cerebral vein pass into

Answer 11

where the falx meets the tentorium

Question 12

if a patient can’t see out of half of both of their eyes what does this indicate

Answer 12

the problem must be before the optic chiasm

Question 13

what could cause a lesion at the optic chiasm which would result in only half of your vision on both eyes

Answer 13

e.g. pituitary adenoma

Question 14

if a patient can’t turn their eye medially and the eyelid can’t stay open what could this indicate

Answer 14

occulomotor nerve problem

Question 15

what muscle turns the eye medially

Answer 15

medial rectus

Question 16

if a child can’t look straight with one eye what could this be

Answer 16

not necessarily a cranial nerve problem, lazy eye is common in childhood

Question 17

what is a dermatome

Answer 17

an area of skin supplied by any particular spinal or cranial nerve

Question 18

how many dermatomes does the trigeminal nerve have

Answer 18

3

Question 19

if you have crusty looking lesions over a particular dermatome what is this called

Answer 19

shingles

Question 20

what virus causes shingles

Answer 20

varicella zoster

Question 21

how does varicella zoster cause shingles

Answer 21

after having chicken pox the virus stays in the trigeminal ganglion and causes shingles by coming down one of the divisions to the face

Question 22

what is particularly concerning about shingles to the opthalmic division

Answer 22

that the cornea could become scarred

Question 23

what is the treatment following a facial palsy caused by local anaesthetic in the lower jaw

Answer 23

close and cover eye with pad until anaesthetic wears off

reassure patient

do a couple of checks to make sure not stroke (other parts of the body normally affected with a stroke)

Question 24

if someone has problems speaking, eating and controlling dentures what nerves/muscles area are affected

Answer 24

• marginal mandibular branch
• buccal branches
• buccinator

Question 25

what nerve supplies sensory sensation to the inside of the larynx including vocal chords

Answer 25

vagus nerve

Question 26

if someone has: 1. not squinting 2. constricted pupil 3. ptosis (drooping eyelid) 4. not sweating on one side of face what might this mean

Answer 26

damage to the sympathetic trunk e.g. horners syndrome can be congenital or aquired from tumour

Question 27

Describe the olfactory nerves

Answer 27

- sensorineural cells whose fibres end in the upper part of the nasal cavity - synapse with neurons in the olfactory bulb - nerves too small to see but bulb and tract are visible

Question 28

describe the optic nerve

Answer 28

- fibres cross over e.g. from right eye to left side of brain - converge at optic chiasm - from the optic chaism axons continue back, and some of the pss through the lateral geniculate body to the superior colliculus - the rest become optic radiation

Question 29

What do the 3rd,4th and 6th cranial nerves do

Answer 29

work together to produce all movements of the eye

Question 30

describe the oculomotor nerve

Answer 30

- originates on medial side of the cerebral peduncles - splits into 2 - goes through superior orbital fissure - innervates most of the external eye muscles through the ciliary ganglion and all of the intrinsic eye muscles

Question 31

describe the trochlear nerve

Answer 31

- emerges dorsally from the brainstem - goes through the superior orbital fissure - innervates only the superior oblique muscle

Question 32

describe the abducens nerve

Answer 32

- emerges just below the pons - goes through the superior orbital fissure - innervates only the lateral rectus which abducts the eye

Question 33

describe the trigeminal nerve

Answer 33

- sensation to the entire face and forehead - innervates muscles of mastication - opthalmic provides sensation for the nose and forehead - maxillary provides sensation to the cheeks nd upper lip - mandibular provides sensation to the lower lip, jaw and anterior to the ear - ganglion is in meckel's cave (invagination of the dura mater)

Question 34

describe the facial nerve

Answer 34

- supplies all the muscles of facial expression and taste sensation from anterior 2/3 of the tongue - emerge just inferior to the pons

Question 35

describe the vestibulocochlear nerve

Answer 35

- two nerves tightly bound together - sensation of balance and hearing - emerge just inferior to the pons and lateral to where abducens begins

Question 36

describe the glossopharyngeal nerve

Answer 36

- relates closely with 10th and 11th CN | - sensory to posterior 1/3 of tongue and general sensation to whole of pharynx

Question 37

describe the vagus nerve

Answer 37

- relates closely with 9th and 11th CN - parasympathetic innervation for a huge portion of the body as far as the splenic flexure of the colon - muscles of pharynx and larynx

Question 38

describe the accessory nerve

Answer 38

- relates closely with CN 9 and 10 - has 2 parts (spinal and cranial portions) - cranial follows the vagus nerve and performs similar functions - spinal accessory innervates the trapezius and sternocleidomastoid muscles

Question 39

describe the hypoglossal nerve

Answer 39

- originates as a number of small rootlets near the midline from the medulla oblongata - goes through a channel in the occipital bone just above the foramen magnum - controls intrinsic and extrinsic muscles of the tongue