Brain Stem and Cranial Nerves

Question 1

Parasympathetic fibres from which 3 nerves are distributed with branches of the trigeminal nerve (V)?

Answer 1

Oculomotor (III), Facial (VII), Glossopharyngeal (IX)

Question 2

Which 2 cranial nerves run in the same line as they both arise from the somatic motor column?

Answer 2

Abducens and hypoglossal

Question 3

Which clinically important tract descends in the pyramids of the medulla?

Answer 3

Corticospinal tract

Question 4

Cranial nerves 6, 7 and 8 emerge at which junction?

Answer 4

Pontomedullary junction

Question 5

What paired structures project down into the interpeduncular fossa?

Answer 5

The mamillary bodies

Question 6

Coma might result from damage to which diffuse network in the brain stem tegmentum?

Answer 6

Reticular formation

Question 7

What is the clinical significance of the area postrema, and which group of drugs act on receptors in this region?

Answer 7

The area postrema is the vomiting centre of the medulla. It is one of the few areas of the brain lacking a blood-brain barrier, which allows detection of the blood contents.

Anti-emetics act on the area postrema receptors.

Question 8

How is the spinal accessory nerve tested clinically?

Answer 8

idk

Question 9

Which thalamic nucleus recieves the optic tract?

Answer 9

Lateral geniculate nucleus

Question 10

The superior and inferior colliculi on the dorsal surface of the mibrain is part of which generalised region of the brainstem?

Answer 10

Tectum - meaning roof

Question 11

What is the clinical term for inhalation of stomach contents?

Answer 11

Aspiration - e.g. in aspiration pneumonia

Question 12

Identify the labelled junctions in the brain stem.

Answer 12

Question 13

The rootlets emerging from the ventrolateral sulcus of the olive constitute which nerve?

Answer 13

Hypoglossal (CNXII)

Question 14

Why is unilateral pupil dilation a warning sign following head injury?

Answer 14

Indicates generalised swelling and compression

Question 15

Which cranial nerve is the only one to emerge from the dorsal surface of the brainstem?

Answer 15

Trochlear - emerges lateral to the frenulum between the inferior colliculi

Question 16

The middle meningeal artery enters the skull via which foramen?

Answer 16

Foramen spinosum

Question 17

The dorsolateral sulcus posterior to the olive is the site of filaments contributing to which cranial nerves?

Answer 17

9, 10, 11

Question 18

Which cranial nerves are mainly responsible for the afferent and efferent limbs of the gag reflex?

Answer 18

Afferent: glossopharyngeal

Efferent: vagus

Question 19

Which cranial nerve arises from the lateral pontine region?

Answer 19

Trigeminal

Question 20

Which limbic lobe nucleus recieves olfactory pathway projections?

Answer 20

Amygdala

Question 21

Sensory and motor fibres to the pharynx and larynx are supplied by which 3 cranial nerves?

Answer 21

9, 10, 11

Question 22

The most posterior portion of the thalamus is known as what?

Answer 22

Pulvinar

Question 23

Compare the clinical signs in an upper versus lower motor neuron facial nerve lesion?

Answer 23

idk

Question 24

Which pontine nerve is especially vulnerable to stretch in raised intracranial pressure? What signs and symptoms would you expect from damage to this nerve?

Answer 24

Trochlear damage: blurry vision, diplopia, rotational (torsional) disturbances in visual field

Question 25

Identify the labelled features of the medulla.

Answer 25

Question 26

What is the role of the olive in motor learning?

Answer 26

The olive supplies sensory information to the cerebellum, allowing for muscle memory and coordination. The olive projects to the opposite cerebellar hemisphere.

Question 27

The locus ceruleus, meaning “violet place” in Latin, is the nucleus that synthesises which neurotransmitter? Where is this nucleus located?

Answer 27

Noradrenaline

In the lateral floor of the fourth ventricle

Question 28

If a patient had an isolated trochlear nerve palsy, what sensory deficit would you expect?

Answer 28

Vertical diplopia

Question 29

What are the clinical features of a unilateral hypoglossal nerve palsy?

Answer 29

idk

Question 30

Which extraocular muscle is supplied by the trochlear nerve?

Answer 30

Superior oblique

Question 31

Identify the labelled features of the midbrain.

Answer 31

Question 32

The substantia nigra supplies dopamine to where?

Answer 32

The striatum

Question 33

Identify the labelled features of the pons.

Answer 33

Question 34

Which cranial nerve emerges from the interpeduncular fossa above the pons?

Answer 34

Oculomotor (III)

Question 35

What are the features of a complete third nerve palsy?

Answer 35

Affected eye will assume a “down and out” position; outward because the lateral rectus maintains muscle tone but the medial rectus becomes paralysed; downwards because the superior oblique is not antagonised by the paralysed superior rectus, inferior rectus and inferior oblique. Drooping eyelid and mydriasis (pupil dilation) will also occur.

Question 36

Name the 12 cranial nerves in order.

Answer 36

I Olfactory II Optic III Oculomotor IV Trochlear V Trigeminal VI Abducens VII Facial VIII Vestibulocochlear (Auditory) IX Glossopharyngeal X Vagus XI Spinal Accessory XII Hypoglossal

Question 37

What is the importance of the middle meningeal artery in traumatic head injury?

Answer 37

Fracture of the pterion may result in rupture of the middle meningeal artery, leading to extradural haematoma

Question 38

Why might damage to the inferior cerebellar peduncle cause gait ataxia?

Answer 38

Loss of coordination due to lack of sensory feedback from peduncle.

Question 39

A stroke affecting which brain stem nucleus might affect speech and swallowing?

Answer 39

Nucleus ambigus