Lecture 4 - Cranial Nerves

Question 1

Name the 3 divisions of CNV, along with their function

Answer 1

Ophthalmic (CNV1); Sensory
Maxillary (CNV2); Sensory
Mandibular (CNV3); Sensory and motor

Question 2

Where is the intracranial part of the course of CNV?

Answer 2

Inferior to the edge of the tentorium cerebelli between the posterior and middle cranial fossae

Question 3

What nerve supplies the skin of the lower eyelid?

Answer 3

CNV2

Question 4

Apart from CNV, which other nerve provides sensory innervation for the face?

Answer 4

Greater auricular nerve (C2, C3)

Question 5

Which nerve provides sensory innervation to the anterior 2/3 of the tongue?

Answer 5

CNV3

Question 6

Name the 3 pairs of jaw closing muscles

Answer 6

Masseter, temporalis and medial pterygoid

Question 7

Where does CNVII leave the base of the skull and then the cranium?

Answer 7

IAM and stylomastoid foramen respectively

Question 8

What is the function of chorda tympani?

Answer 8

Sensory innervation of taste buds in the anterior 2/3 of the tongue and parasympathetic supply to the submandibular and sublingual salivary glands

Question 9

Which muscle reduces stapes movement and why?

Answer 9

Strapedius; to protect the internal ear from excessive noise

Question 10

Which muscle dampens the noise produced by chewing?

Answer 10

Tensor tympani

Question 11

How do you clinically test CNVII motor function?

Answer 11

Ask the patient to; frown, close eyes tightly, smile and puff out cheeks

Question 12

What is the intracranial course of CNIX?

Answer 12

Directly towards jugular foramen in the posterior cranial fossa

Question 13

Which cranial nerve is contained within the carotid sheath?

Answer 13

CNX

Question 14

How do you clinically test CNXI?

Answer 14

Ask the patient to shrug their shoulders and turn their head to look up towards the opposite side

Question 15

Where does CNXII leave the base of the skull?

Answer 15

Hypoglossal canal