Tutorial 2

Question 1

A 62-year old homemaker was involved in a motor vehicle accident 5 days ago. She sustained fractures of the skull, both femurs, and the right tibia. She complains of double vision. She is having trouble reading since the accident. As part of your assessment, you perform a screening for all cranial nerves relevant for the eyes.
Findings: all tests negative, except for an inability to look inward and downward with the right eye.

Which cranial nerves did you test?
Which cranial nerve(s) is(are) affected?

Answer 1

CN 3 : Oculomotor
CN 4: Trochlear
CN 6: Abducens

Inability to look down and in = superior oblique
meaning the Trochlear nerve (CN 4) is affected.

Question 2

A 46-year old engineer is complaining of double vision. He cannot read or drive unless he closes one eye. As part of your assessment, you perform a cranial nerve screening for the eyes.
Findings:
-When asked to look straight ahead, the patient’s right eye looks outward and down.
-The patient is unable to move the eye medially or up and in.
-The patient can only open the right eyelid halfway.

Which cranial nerve/s is/are affected?

Answer 2

eyelid halfway = levator palpabrae
medial rectus and rectus inferior affected

= CN 3: Oculomotor affected

Question 3

Which system originates from and has its nucleus in the lateral horn of the spinal cord?

Answer 3

Sympathetic

Question 4

The anterior and posterior spinal arteries anastomose with which vessels to supply blood to the spinal cord?

Answer 4

The anterior and posterior radicular arteries

Question 5

A 50-year old woman awoke with inability to move the left side of her face. As part of your assessment, you perform a cranial nerve screening, particularly focused on the face.

Findings: On cranial nerve testing, facial sensation is intact. 1. which cranial nerve is not affected?

The patient has full control of the muscles of mastication and the tongue.
2. which cranial nerve is not affected?

The patient has full control of the neck rotation.
3. which cranial nerve is not affected?

There is drooping of the left side of the faceThe patient has complete lack of movement of the muscles of facial expression on the left.
4. Which cranial nerve(s) is(are) affected?

Answer 5

1. Trigeminal nerve CN 5 : 3 branches
2. Hypoglossal nerve CN 12
3. Spinal accessory nerve CN 11
4. Fascial nerve CN 7

Question 6

A 34-year old man reports progressive hoarseness,dysphagia, and weakness of the neck muscles. As part of your assessment, you perform a cranial nerve screening.

Findings:
The patient’s voice is hoarse and breathy in quality when he talks.

Left trapezius and sternocleidomastoid muscles are Grade 4 strength.

His tongue deviates to the left on protrusion.

Which cranial nerve(s) is(are) likely affected? On which side –left or right?

Answer 6

The patient’s voice is hoarse and breathy in quality when he talks.
= CN 9 and 10 - Glossopharyngeal and Vagus

Left trapezius and sternocleidomastoid muscles are Grade 4 strength.
= CN 11 - Spinal Accessory nerve

His tongue deviates to the left on protrusion.
= CN 12 - Hypoglossal nerve on LEFT

Which cranial nerve(s) is(are) likely affected? On which side –left or right?
=LEFT

Question 7

What is traveling is the basilar groove?

Answer 7

Basilar artery

Question 8

Name all the cranial nerves in order and their major function

Answer 8

I Olfactory (Smell)
II Optic (Sight)
III Oculomotor (Moves eyelid and eyeball and adjusts the pupil and lens of the eye)
IV Trochlear (Moves eyeballs)
V Trigeminal (Facial muscles incl. chewing; Facial sensations)
VI Abducens (Moves eyeballs)
VII Facial (Taste, tears, saliva, facial expressions)
VIII Vestibulocochlear (Auditory)
IX Glossopharyngeal (Swallowing, saliva, taste)
X Vagus (Control of PNS e.g. smooth muscles of GI tract)
XI Accessory (Moving head & shoulders, swallowing)
XII Hypoglossal (Tongue muscles - speech & swallowing)