Brainstem part III: The Medulla

Question 1

What structures do we find in the medulla?

Answer 1

1. Cranial nuclei for IX, X, XI and XII.
2. The pyramids, and pyramidal decussation.
3. Olivary nuclei.
4. Aspects of other cranial nerves, the nucleus ambiguus, and nucleus solitarius.
5. Reticular formation, ascending and descending tracts.
6. Trigeminal

Question 2

identify

Answer 2

Question 3

identify

Answer 3

Question 4

What do the olives (olivary nuclei) do?

Answer 4

1. They send fibers to cerebellum via inferior cerebellar peduncle, and are involved with the cerebellum in the coordination of voluntary movement.
2. connect the two cerebellar hemispheres, which makes sense since movements on both sides of the body need to be coordinated.

Question 5

CN 11 has 2 parts, what are they?

nucleus solitarious receives what info?

Answer 5

cranial: part of nucleus ambiguous

spinal part: innervation of trapezius and sternocleidomastoid

taste information

Question 6

what part of the medulla is this?

Answer 6

caudal medulla

Question 7

identify the parts of the caudal medulla

Answer 7

Question 8

what cranial nerves come from behind the olives?

Answer 8

9 and 10

Question 9

how many vestibuli nuceli are there?

what are they?

spinal tract and nucleus of trigeminal nerve, will extend to what spinal nerves?

Answer 9

2: medial and lateral

C2-C3

Question 10

CN 9 will exit between what 2 structures?

In the caudal medulla the Lateral spinothalamic tract will be in the process of becoming what?

Answer 10

between olivary nucleus and pyramids.

spinal lemniscus

Question 11

what do i look for when transitioning from the rostral medulla to caudal medulla?

Answer 11

nucleus cuneatus, nucleus gracilis + fasciculus cuneatus, fasciculus gracilis

Question 12

what part of the medulla is this?

how do you know?

Answer 12

level of decussation of the pyramids

• you can see the fasciculus cuneatus and gracilis only, as well as the spinothalamic and spinocerebellar tracts and Spinal root of CN XI, going to sternocleidomastoid and trapezius muscles.

Question 13

What type of syndrome do we have in the picture?

what are the another 2 names for this type of lesion?

Answer 13

Medial Medullary Lesion

Inferior Alternating Syndrome or also known as Dejerne Syndrome.

Question 14

Why does Medial Medullary Syndrome happen?

What symptoms do we see?

Answer 14

Occlusion/damage to anterior spinal artery, or vertebral artery

Symptoms:

1. Contralateral hemiparesis.
2. Loss of proprioception, vibratory and discriminatory touch.
3. Ipsilateral paralysis of tongue muscles.

Question 15

what type of syndrome will we see here?

what is another name for this?

What symptoms can we see here?

Answer 15

Lateral Medullary Syndrome of Wallenberg

PICA Syndrome

Symptoms include:

1. Dysphagia
2. Dysarthria
3. Analgesia and thermoanesthesia on ipsilateral face
4. Vertigo, nausea, vomiting, nystagmus
5. Ipsilateral Horner’s syndrome
6. Gait and limb ataxia
7. Contralateral loss of pain and temperature sense
8. dysphonia (hoarseness of voice) (damage to nucelus ambiguus)

Question 16

Identify the blood supply to the different areas of the Medulla

Answer 16

Question 17

identify the structures of the posterior medulla

Answer 17

Question 18

what will you never see in lateral medullary syndrome?

Answer 18

tongue issues

dorsal column issues