S4 L1 Cranial Nerves I-VI

Question 1

Bigger picture:

• What do cranial nerves supply?
• Part of which system?
• Associated with which part of the brain?
• What type (sensory, motor,…) of nerves are cranial nerves?

Answer 1

Question 2

Signs and Symptoms from structures innervated with cranial nerves
- 3 locations cranial nerve injuries can arise in?

Answer 2

Question 3

Cranial Nerves Topography:
- How to remember the location of the ‘origin’ of the cranial nerves (which part of the brain)

Answer 3

Question 4

List the names of the first 6 cranial nerves

Answer 4

CN I Olfactory
CN II Optic
CN III Oculomotor
CN IV Trochlear
CN V Trigeminal
CN VI Abducens

Question 5

• *1. CN 1 - Olfactory nerve**
• Origin of this nerve
• How is it tested
• Medical names describing the affect if this nerve doesn’t ‘work’
• Causes of problems with this nerve

Answer 5

Question 6

Olfactory nerve cont.

• Route of olfactory nerve
• Where does this nerve reach?

Answer 6

Question 7

• *2. CN II Optic nerve**
• Role
• Location of the origin
• Important characteristic of the optic nerve - can cause issues with raised ICP…
• Test (3)
• On clinical examination, will…

Answer 7

Question 8

Optic nerve cont.

• Causes of issues
• What is an ophthalmoscopy - what does a normal and abnormal one look like?

Answer 8

Question 9

Optic nerve cont.

• Pathway of optic nerve
• Location of the brain that processes it

Answer 9

Question 10

Label the following:

Answer 10

Question 11

Optic nerve cont.

• Role of: Optic nerve, optic chaism, optic tract
• The affect of pathologies in different regions

Answer 11

Question 12

• *3. CN III - Oculomotor**
• Origin
• Role (3 mains)
• Tests
• On examination (4 things…)

Answer 12

Question 13

CN III - Oculomotor cont.
- Causes

Look at picture on this side, after looking at the answer

Answer 13

Question 14

Oculomotor cont.

• Route of this nerve and its divisions
• Blood vessels
• Second lot of blood vessels

Answer 14

Question 15

Oculomotor cont.
- Dissection

Answer 15

Question 16

• *4. CN IV - Trochlear nerve**
• Role
• Origin
• Test
• Examination

Answer 16

Question 17

Trochlear nerve cont.
- Causes

Answer 17

Question 18

Trochlear nerve cont.

• Route
• Dissection

Answer 18

Question 19

• *5. CN VI - Abducens**
• Role
• Origin
• Examination
• Cause

Answer 19

ORIGIN: PONTOMEDULLARY JUNCTION

Question 20

• *6. CN VI Abducens cont.**
• Route
• Route is vulnerable because…
• Test

Answer 20

Question 21

Summary: of cranial nerves supply eye muscles

• Common route
• Which nerves?
• Pathology in the cavernous sinus, can affect…

Answer 21

Question 22

• *5. CN V - Trigeminal
• ** Role
• Origin
• Tests

Answer 22

Branches have an extensive distribution supplying
skin of the face and scalp and deep structures of
the face

Remember to check BOTH sides

Question 23

Trigeminal nerve cont.
- Some conditions

Answer 23

Question 24

Trigeminal nerve
- Branches

Answer 24

Question 25

Summary of trigeminal nerve: - Divisions and what it passes through Branches are covered next week

Answer 25

Question 26

GW: A 25 year old man is brought the Emergency Department (ED) by his friends. Earlier in the day he was struck on the side of his head by a cricket ball. He was initially knocked out, but regained consciousness within a minute. Over the course of the day he complained of a headache. His friends became concerned when he started to become increasingly confused and drowsy in the evening. After an examination of the man, the ED doctor arranges for an urgent CT head scan. Showed extradural haemorrhage. Q in pic Also: Q: Why has ptosis not developed?

Answer 26