Session 8: Integrated Case Studies

Question 1

The image below is a coronal section through the primary motor cortex. Which area of the primary motor cortex is responsible for conscious control of left half of the face and arm?

Answer 1

E and F

Question 2

Patient comes in with facial nerve palsy.

What muscle(s) is affected to account for the appearance by the eye?

Answer 2

Orbicularis oculi meaning the patient can’t close his eye.

Question 3

Facial nerve palsy.

What muscle(s) is affected to account for the appearance by the mouth?

Answer 3

Zygomatic major and minor

Risorius

Orbicularis oris

Question 4

What might the doctor have asked the patient to do to test the integrity of the facial nerve?

Answer 4

General facial expression

Alteration of taste

Dryness of eyes

Dryness of mouth

Hearing

Question 5

Why might the doctor examine the parotid gland in a patient presenting with facial nerve palsy?

Answer 5

Facial nerve runs through the parotid gland. If there is pathology it can cause impingement and irritation of the nerve.

Question 6

What are the three branches of the facial nerve that arise within the petrous temporal bone?

Answer 6

Greater petrosal nerve

Chorda tympani

Nerve to stapedius

Question 7

Why might a patient with a facial nerve lesion complain of sensitivity to loud noises (hyperacusis)?

Answer 7

Palsy of stapedius which prevents excessive noise forming.

Question 8

Give two reasons why the patient’s eye might be at risk of drying and injury as a result of a facial nerve lesion.

How could this be managed?

Answer 8

Corneal reflex not working

Can’t blink leading to drying out

Lacrimal glands which are innervated by parasympathetics from chorda tympani are not working.
Less protection to foreign bodies.

Eye drops and eye patch

Question 9

Why might the doctor also want to examine the ear more closely?

Answer 9

Acute otitis media and cholesteotomas which can cause facial nerve palsy.

Also Ramsay-Hunt syndrome which is shingles of the facial nerve presenting in the external ear.

Question 10

Name three conditions involving structures or areas of the ear that can present with otalgia.

Answer 10

Acute otitis media

Otitis externa

Perichondritis

Question 11

Which nerves are involved in innervating structures of the external and middle ear (those carrying general sensory afferent)?

Answer 11

Glossopharyngeal (middle ear + oropharynx + tonsils)

Trigeminal via auriculotemporal

Vagus nerve (ear + larynx + laryngopharynx)

C2, C3

Question 12

To explore a potential cause for referred pain to the ear the presence of pathology in which other areas of the head and neck should be determined?

Answer 12

Mouth

Tonsils

Lymph nodes

Cancers

Question 13

The doctor enquires about the presence of red flags and also examins the oropharynx and palpates for cervical lymphadenopathy.

What are red flags and what might these have been in this patient’s case?

Answer 13

In case it is cancer

Weight loss

Changing/hoarse voice

Lumps

Difficulty swallowing

Ear pain

Question 14

Why did the doctor examine the oropharynx and palpate the cervical lympadenopathy?

Answer 14

Shared sensory with glossopharynx nerve.

Question 15

What features on palpation of a lymph node would be indicative of metastatic involvement?

Answer 15

Immobile

Non-tender

Hard

Irregular

Question 16

What do you think could be the underlying diagnosis and what would be the appropriate next step for the GP to take in managing this patient?

Answer 16

Referral to ENT

Question 17

What is the likely diagnosis?

Answer 17

Left ear?

Acute otitis media

(Fever, bulging, runny nose)

Question 18

What features in the girl’s history and examination of the tympanic memrbane led to your diagnosis?

Answer 18

Bulging and red tympanic membrane

Question 19

Why is this condition more common in young children that in adults?

Answer 19

Because the eustachian tube is shorter and more horizontal in children. That makes it easier for pathogens to make their way up there from the nasopharynx.

Question 20

What are the most common pathogens involved in causing acute otitis media?

Answer 20

Viral (most common)

Streptococcus pneumoniae

Haemophilus influenzae

Question 21

What condition has now developed?

Answer 21

Mastoiditis

Question 22

Explain with reference to the anatomy of the ear, how the original infection was able to spread leading to the condition seen in the above image?

Answer 22

Middle ear has a connection (aditus->mastoid antrum-> mastoid air cells)

Infection can travel here and settle in the mastoid air cells.

Question 23

Name two other anatomical structures within the skull which can in any patient be affected by the spread of infection from the middle ear?

Answer 23

Temporal lobe

Sigmoid sinus -> thrombosis of sigmoid sinus

Dura -> meningitis