Week 4 SDL and Practical: Brainstem, cerebellum and cranial nerves

Question 1

Which sub divisions of the brain make up the brainstem?

Answer 1

mesencephalon (midbrain)
metencephalon (pons)
myelencephalon (medulla oblongata)

Question 2

Where is the pyramidal decussation?

Answer 2

anterior median fissure of the medulla oblongata

Question 3

Where is the gracile tubercle and fascicle located in the brainstem?

Answer 3

midline dorsal medulla

Question 4

What structures are located in the dorsal medulla?

Answer 4

• lateral and medial geniculate nucleus
• superior and inferior colliculus
• trochlear nerve
• interpeduncular fossa
• superior, middle and inferior cerebellar peduncle
• choroid plexus in roof of 4th ventricle
• cuneate/gracile tubercle/fasciculus

Question 5

State all the features on the ventral surface of the medulla oblongata

Answer 5

pyramids
olives
anterior median fissure
decussation of pyramids
antero-lateral sulcus
postero-lateral sulcus
CN IX, X, XI, XII

Question 6

State all the features on the ventral surface of the pons

Answer 6

basilar groove

CN V, VI, VII, VIIII

Question 7

State all the features on the ventral surface of the midbrain

Answer 7

optic chiasma
optic tract
pituitary stalk
mammillary bodies
cerebral peduncles
interpeduncular fossa
CN III, IV

Question 8

How is the medulla divided?

Answer 8

into the open medulla and the closed medulla

the medulla becomes open when the central canal opens into the 4th ventricle

Question 9

What is the function of the cerebellum?

Answer 9

co-ordination of movement

maintenance of balance and posture

Question 10

To which region of the brainstem does each cerebellar peduncle connect

Answer 10

superior- midbrain
middle - pons
inferior - medulla

Question 11

Which 3 arteries supply the cerebellum and are they part of the anterior system of vessels (internal carotid system) or of the posterior system (vertebral baislar)

Answer 11

All originate from the vertebral basilar system:

• superior cerebellar artery (SCA)
• anterior inferior cerebellar artery (AICA)
• posterior inferior cerebellar artery (PICA)

Question 12

What is dysdiadochokinesis?

Answer 12

impaired ability to perform rapid, alternating movements

caused by cerebellar damage

Question 13

What is past pointing and how do you test it?

Answer 13

past pointing - the inability to place a finger or some other body part accurately on a selected point
-finger-to-nose test

Question 14

What is the test for dysdiadochokinesis?

Answer 14

ask patient to clap by alternating the palmar and dorsal surfaces of the hand as fast as possible
repeat with other hand

Question 15

Which cranial nerves emerge from the cerebellopontine angle?

Answer 15

CN VII, VIII

Question 16

Which cranial nerve emerges from the interpeduncular fossa?

Answer 16

CN III

Question 17

Which cranial nerve emerges immediately lateral to the medullary pyramid?

Answer 17

CN XII

Question 18

Which cranial nerves emerges lateral to the olive?

Answer 18

CN IX, X

Question 19

Which cranial nerve emerge from the dorsal surface of the brainstem

Answer 19

CN IV

Question 20

What is the consequence of damage to the olfactory nerve?

Answer 20

anosmia - absence of sense of smell

Question 21

Which cranial nerve supplies the dura?

Answer 21

trigeminal

Question 22

Where are the cell bodies of most of the trigeminal sensory fibres located?

Answer 22

in the trigeminal ganglion - located in the lateral wall of the cavernous immediately lateral to the pituitary gland

Question 23

Which two reflexes are associated with the trigeminal nerve

Answer 23

1. corneal reflex - an involuntary blinking of the eyelids elicited by stimulation of the cornea (such as by touching or by a foreign body)
2. jaw-jerk reflex

Question 24

What is trigeminal neuralgia?

Answer 24

chronic pain caused by trigeminal nerve - even mild stimulation of your face such as brushing your teeth or putting on makeup - may trigger a jolt of excruciating pain

Question 25

Where do the 5 branches of the facial nerve arise?

Answer 25

within the parotid gland

Question 26

The chorda tympani carries fibres between which nerves?

Answer 26

facial nerve to supply taste to the anterior 2/3rds of tongue and the lingual nerve as it contains secretory fibres for the sublingual and submaxillary glands

Question 27

Which nerve supplies the lacrimal gland?

Answer 27

the greater petrosal nerve (branch of facial nerve)

Question 28

What is tinnitus?

Answer 28

ringing in ear

Question 29

Which nerve innervates the vocal folds?

Answer 29

vagus nerve

Question 30

What is the gag reflex, which cranial nerve does it test and why is it important?

Answer 30

- Pharyngeal reflex when something touches the roof of your mouth, the back of your tongue or throat or the area around your tonsils - glossopharyngeal nerve - Prevents choking and keeps us from swallowing potentially harmful substances

Question 31

what are the two parts of the accessory nerve?

Answer 31

- cranial part | - spinal part

Question 32

What are autonomic ganglia?

Answer 32

- clusters of neuronal cell bodies and their dendrites - they are essentially a junction between autonomic nerves originating from the central nervous system and autonomic nerves innervating their target organs in the periphery

Question 33

What are the four autonomic ganglia of the head and neck?

Answer 33

1. pterygopalantine 2. ciliary 3. otic 4. submandibular

Question 34

What is the function of the pterygopalantine ganglia?

Answer 34

receives parasympathetic fibres from the facial nerve and supplies the lacrimal glands, palantine glands and mucosa of the nasal cavity

Question 35

What is the function of the otic ganglia?

Answer 35

receives parasympathetic fibres from the glossopharyngeal nerve and supplies the parotid gland

Question 36

What is the function of the submandibular ganglia?

Answer 36

receives parasympathetic fibres from the facial nerve and supplies the submandibular and sublingual glands

Question 37

Which cranial nerves are involved in the pupillary light reflex and how do we test it?

Answer 37

- CN II and CN III - dim the lights and look at a distant object - shine torch into eyes from each side - look to see if patients pupils constrict in response to light

Question 38

What are the symptoms of horner's syndrome?

Answer 38

- partial ptosis - constricted pupil (miosis) - reduced facial sweating - facial flushing

Question 39

What is the substantia nigra?

Answer 39

in the midbrain | dopamine containing neurons

Question 40

What structure seperates the two cerebellar hemispheres

Answer 40

vermis

Question 41

What are nodules?

Answer 41

ventral part of vermis of cerebellum | found on the midline on the superior surface

Question 42

What seperates the anterior and posterior lobes of the cerebellum?

Answer 42

primary fissure

Question 43

In what way do fibres run across the pons?

Answer 43

transverse | because it attaches the two hemispheres on the left and right

Question 44

Which cranial nerves go through the jugular foramen?

Answer 44

CN IX, X and XI

Question 45

In a hypoglossal nerve lesion, does the tongue deviate away from the side of lesion or toward the side of lesion?

Answer 45

toward the side of lesion