Cranial + Peripheral Nerves

Question 1

What is Bell’s palsy?

Answer 1

facial paralysis due to CN7 dysfunction

Question 2

What is Ramsay Hunt?

Answer 2

VZV on face causing blisters, weakness, altered taste, loss of function

Question 3

What is trigeminal neuralgia?

Answer 3

Pain affecting trigeminal nerve - sudden severe electric shock type pain in jaw, gums + teeth

Question 4

Signs + causes of olfactory nerve lesion

Answer 4

Reduced taste + smell

Trauma, frontal lobe tumor, meningitis

Question 5

Signs of optic

nerve lesion

Answer 5

Visual field defects
Pupillary abnormalities
Optic neuritis
Papilloedema

Question 6

Signs + causes of oculomotor nerve lesion

Answer 6

Fixed dilated pupil which doesn’t accomodate
Then ptosis
Caused by DM, GCA, syphilis, posterior communicating artery aneurysm

Question 7

Signs + causes of trochlear nerve lesion

Answer 7

Diplopia due to weakness of downward + inward eye movement

Trauma to orbit

Question 8

Signs + causes of trigeminal nerve lesion

Answer 8

Reduced sensation/ dysathesia over affected area
Weakness of jaw clenching
Jaw deviates to weak side when mouth is opened (if LMN lesion)
Causes: trigeminal neuralgia, herpes, nasopharyngeal carcinoma, acoustic neuroma

Question 9

Signs + causes of abducent nerve lesion

Answer 9

Inability to look laterally, eye deviated medially

Causes: MS, pontine CVA

Question 10

Signs + causes of facial nerve lesion

Answer 10

Facial weakness (forehead is paralysed)
Bell’s palsy, polio, otitis media, cerebellopontine angle tumors, Ramsay Hunt, Lyme
UMN spares forehead:
stroke, tumor

Question 11

Signs + causes of vestibulocochlear nerve lesion

Answer 11

Unilateral sensorineural deafness, tinnitus

Causes: Pagets, Meniere’s, herpes, neurofibroma, aminoglycosides, furosemides

Question 12

Signs + causes of glossopharyngeal nerve lesion

Answer 12

Unilateral lesions don’t cause any deficit because of bilateral corticobulbar connections
Bilateral = pseudobulbar palsy
Cause = trauma, brainstem lesions, cerebellopontine angle + neck tumors, polio, Guillain-Barre

Question 13

Signs + causes of vagus nerve lesion

Answer 13

Nasal speech + nasal regurg of food, hoarseness, bovine cough
Causes: trauma, brainstem lesions, cerebellopontine angle tumours, GBS

Question 14

Signs + causes of accessory nerve lesion

Answer 14

Weakness + wasting of sternocleidomastoid + trapezius

Causes: trauma, brainstem lesions, cerebellopontine angle tumours, GBS

Question 15

Signs + causes of hypoglossal nerve lesion

Answer 15

LMN lesion = wasting of ipsilateral side of tongue (deviates towards affected side)
Causes: polio

Question 16

What combined cranial nerve lesions are caused by cerebellopontine angle tumors?

Answer 16

7, 8, then 5 and sometimes 9

Question 17

What is Gradenigo’s syndrome?

Answer 17

Lesions within petrous temporal bone

5 + 6 lesions

Question 18

What can cause combined lesions in 3, 4 + 6?

Answer 18

Stroke, tumor, Wernicke’s encephalopathy, aneurysms, MS, myasthenia gravis, meningitis

Question 19

What are the main causes of upper extremity nerve injury?

Answer 19

Compression
Transection
Ischemia 
Inflammation
Neuronal degeneration 
Radiation

Question 20

What is the most common mononeuropathy in the upper limb?

Answer 20

Carpal tunnel syndrome

Question 21

What is used to identify + classify nerve disorders?

Answer 21

Electromyography

Nerve conduction studies

Question 22

S+S of carpal tunnel

Answer 22

Pain or paraesthesia in median nerve area

Worse at night

Question 23

Management of carpal tunnel

Answer 23

Wrist splinting
Glucocorticoid injections
Surgery

Question 24

S+S of ulnar neuropathy at elbow

Answer 24

Sensory loss + paresthesia over digits 4 + 5

Weakness of interossesous muscles in hand

Question 25

What is the typical presentation of peroneal neuropathy at fibular neck?

Answer 25

Acute foot drop