Corrections 2 Flashcards
Lesion to which cranial nerve can cause diplopia when looking laterally?
CN VI (abducens)
i.e. defective abudction
Features of a CN IV (trochlear) lesion?
Palsy results in defective downward gaze → vertical diplopia
Which CN is involved in head & shoulder movement?
CN XI (accessory nerve)
Role of CN XII (hypoglossal)?
Tongue movement –> tongue will deviate towards the side of the lesion
Role of CN X (vagus)?
- phonation
- swallowing
- innervates viscera
Features of CN X lesion?
Lesions may result in;
- uvula deviates away from site of lesion
- loss of gag reflex (efferent)
1st line mx of focal seizures?
lamotrigine or levetiracetam
2nd line mx of focal seizures?
Carbamazepine
What should be considered in patients who present with falls soon after a diagnosis of Parkinson’s disease?
Investigate for an alternative diagnosis –> e.g. progressive supranuclear palsy (a parkinson plus syndrome)
What is a fasciculation?
A spontaneous, involuntary muscle contraction and relaxation (i.e. a muscle twitch)
What is the most common presentation of ALS?
Asymmetric limb weakness
What derm feature may be present in tuberous sclerosis?
Depigmented ‘ash leaf’ spots
Features of a lacunar stroke?
presents with 1 of the following:
1) unilateral weakness (and/or sensory deficit) of face and arm, arm and leg or all three.
2) pure sensory stroke.
3) ataxic hemiparesis
1st line medications for spasticity in MS?
Baclofen & gabapentin
What is the mainstay of mx of cervical myelopathy?
Decompressive surgery –> refer to spinal surgery/neurosurgery!
Where is Wernicke’s area?
Left temporal lobe (superior temporal gyrus)
Is Broca’s area on the L or the R?
L
Mx of MS acute relapse?
High-dose steroids (e.g. oral or IV methylprednisolone) for 5 days
It should be noted that steroids shorten the duration of a relapse and do not alter the degree of recovery (i.e. whether a patient returns to baseline function)
Lesions at which nerve root will cause finger abduction weakness?
T1
What is a PICA lesion also known as?
Lateral medullary syndrome
What is ‘saturday night palsy’?
Occur when there is compression of the radial nerve (typically when an intoxicated person falls asleep with their arm draped over a hard surface like a chair back).
Feautres of springomyelia?
Cape-like loss of pain and temperature sensation
1st line investigation in springomyelia?
MRI spine –> to exclude a tumour or tethered cord
Mx of restless leg syndrome?
Dopamine agonist e.g. ropinirole
What is thoracic outlet syndrome?
A disorder involving compression of brachial plexus, subclavian artery or vein at the site of the thoracic outlet.
Sensory loss in a common peroneal nerve lesion?
Sensory loss over dorsum of foot
What is the most common radiculopathy affecting the lumbosacral spine?
L5 radiculopathy
How does L5 radiculopathy typically present?
1) Back pain that radiates down the LATERAL aspect of the leg into the foot.
2) Loss of sensation over LATERAL aspect of calf and foot
How does S1 radiculopathy typically present?
1) Back pain that radiates down the POSTERIOR aspect of the leg into the foot
2) Strength may be reduced in leg extension (gluteus maximus), foot eversion, plantar flexion, and toe flexion
3) Sensation reduced on the POSTERIOR aspect of the leg and lateral foot
What is a wide based gait with a loss of heel to toe walking called?
Ataxic gait
IV mannitol vs IV dexamethasone in raised ICP?
IV mannitol –> used to treat raised ICP 2ary to traumatic brain injury
IV dexamethasone –> used to treat ICP 2ary to vasogenic oedema from CNS or neoplasms.
Mechanism of IV mannitol in raised ICP?
IV mannitol is a hypertonic agent which increases systemic osmolality, causing an osmotic shift of water out of the brain parenchyma.
What is a cervical rib?
A congenital defect in which an additional rib grows from the base of the neck just above the collar bone.
What is a risk of a cervical rib?
Thoracic outlet syndrome –> compression of brachial plexus, subclavian artery or vein at the site of the thoracic outlet.
Mx of all patients with degenerative cervical myelopathy?
Should all be referred for assessment by specialist spinal services.
Only effective treatment is decompressive surgery.
Mx of a brain abscess?
IV 3rd-generation cephalosporin (e.g. cephtriaxone) + metronidazole
What is pituitary apoplexy?
A rare and life-threatening complication of a pituitary adenoma.
Sudden enlargement of a pituitary tumour 2ary to haemorrhage or infarction.
Precipitating factors of pituitary apoplexy?
- HTN
- pregnancy
- trauma
- anticoagulation
Features of pituitary apoplexy?
- sudden onset headache similar to that seen in SAH
- vomiting
- neck stiffness
- visual field defects: classically bitemporal superior quadrantic defect
- extraocular nerve palsies
- features of pituitary insufficiency
e.g. hypotension/hyponatraemia secondary to hypoadrenalism
What imaging is diagnostic in pituitary apoplexy?
MRI
Mx of pituitary apoplexy?
1) Urgent steroid replacement due to loss of ACTH
2) Careful fluid balance
3) Surgery
Autonomic dysreflexia can only occur if the spinal cord injury occurs above what level?
Above T6
Features of a common peroneal nerve lesion?
1) Foot drop
2) Weakness of foot dorsiflexion
3) Weakness of foot eversion
4) Weakness of extensor hallucis longus
5) Sensory loss over the dorsum of the foot and the lower lateral part of the leg
6) Wasting of the anterior tibial and peroneal muscles
What 2 movements are impacted in a common peroneal nerve lesion?
1) foot dorsiflexion
2) foot eversion
3) toe extension
Location of sensory loss in a common peroneal nerve lesion?
Over the dorsum of the foot and the lower lateral part of the leg
Is an ENT referral indicated in simple cases of Bell’s palsy?
No - only in refractory cases
Which nerve is at risk during fracture of the neck of the humerus?
Axillary nerve
Which nerve is at risk during shoulder dislocation?
Axillary nerve
In what condition are subungual fibromas found?
Tuberous sclerosis
Inheritance of tuberous sclerosis?
Autsomal dominant
When is a CT head indicated in a TIA?
If patient is taking anticoagulants
What are the 1st line investigations for patients with a suspected vestibular schwannoma?
1) Audiogram
2) Gadolinium-enhanced MRI head
When is a combination of thrombolysis AND thrombectomy recommended for patients with an acute ischaemic stroke?
In those who present within 4.5 hours
WCC findings in NMS?
leukocytosis
Long-term secondary prevention after 21 days
What sensory features are seen in MS?
1) pins/needles
2) numbness
3) trigeminal neuralgia
4) Lhermitte’s syndrome: paraesthesiae in limbs on neck flexion
What motor feature is seen in MS?
Spastic weakness: most commonly seen in legs
Define spasticity
Spasticity is stiff or rigid muscles.
Cerebellar features of MS?
1) ataxia (more often seen during an acute relapse than as a presenting symptom)
2) tremor
Other features seen in MS:
1) urinary incontinence
2) sexual dysfunction
3) intellectual deterioration
Mx of a myasthenic crisis?
1) supportive
2) IV immunoglobulin or plasma exchange
Characteristic features of Guillain-Barre syndrome?
1) Progressive, symmetrical weakness of all the limbs (typically ascending)
2) Reduced or absent reflexes
3) Sensory symptoms tend to be mild (e.g. distal paraesthesia) with very few sensory signs
Pyridostigmine is used in the mx of mysthenia gravis.
What is the mechanism of this?
Long-acting acetylcholinesterase inhibitor
What is affected in Weber’s syndrome?
branches of the posterior cerebral artery that supply the midbrain
2 features seen in Weber’s syndrome?
1) ipsilateral CN III palsy
2) contralateral weakness of upper and lower extremity
What are some drugs that can cause Stevens-Johnson syndrome (SJS)?
- carbamazepine
- lamotrigine
- allopurinol
- sulfonamide
- phenobarbital
Reflexes in Guillain-Barre?
Reduced or absent
Mx of bladder dysfunction in MS?
may take the form of urgency, incontinence, overflow etc
1) get an US first to assess bladder emptying
if if significant residual volume → intermittent self-catheterisation
if no significant residual volume → anticholinergics may improve urinary frequency
Mx of oscillopsia in MS (when visual fields appear to oscillate)?
Gabapentin
Does the parietal lobe carry fibres from the superior or inferior optic radiation?
Superior
Inferior homonymous quadrantanopias are caused by lesions of what?
Superior optic radiations in the parietal lobe
Superior homonymous quadrantanopias are caused by lesions of what?
Inferior optic radiations in the temporal lobe
What 2 TIA mimics require exclusion?
1) hypoglycaemia
2) intracranial haemorrhage
Mx of TIA:
1) Resolved TIA symptoms, awaiting specialist review within 24 hours
2) Reviewed by specialist, initial 21 days when at high risk of further events
3) Long-term secondary prevention after 21 days
1) Aspirin
2) Aspirin + clopidogrel
3) Clopidogrel (75mg)
What can be given in TIA in patients at risk of bleeding (i.e. not suitable for dual antiplatelet therapy)?
Clopidogrel 300mg loading dose followed by 75mg OD
What nerve innervates adductor pollicis?
Ulnar nerve
What movement is impacted in an ulnar nerve lesion?
Lossof thumb adduction due to adductor pollicis weakness
What is Arnold-Chiari malformation?
The downward displacement, or herniation, of the cerebellar tonsils through the foramen magnum.
May be congenital or acquired through trauma.
Features of an Arnold-Chiari malformation?
1) non-communicating hydrocephalus may develop as a result of obstruction of CSF outflow
2) headache
3) springomyelia
Which opioid can sometimes be used in the mx of neuropathic pain?
Tramadol (weak opioid agonist and a reuptake inhibitor of serotonin and norepinephrine).
What sign is usually seen on CT immediately after symptom onset in an acute ischaemic stroke?
Hyperdense artery sign –> this is usually visible immediately in contrast to changes in the parenchyma which usually evolve as the ischaemia within the tissue is established.
Where is the chemoreceptor trigger zone located?
In the medulla oblongata
What nerve is responsible for finger adduction?
Ulnar nerve
What nerve supplies the sergeants patch?
Axillary nerve
Which nerve is responsisble for finger & wrist extension?
Radial nerve
What is Creutzfeldt-Jakob disease characterised by?
Rapid onset dementia and myoclonus
2 features seen in a posterior cerebral artery lesion?
1) contralateral homonymous hemianopia with macular sparing
2) visual agnosia
Features of progressive supranuclear palsy?
1) postural instability
2) impairment of vertical gaze
3) parkinsonism
4) frontal lobe dysfunction
This is a ‘Parkinson Plus’ syndrome
Gold standard investigation for degenerative cervical yelopathy?
MRI cervical spine
Inheritance of Charcot-Marie tooth disease?
Autosomal dominant
Features of CN IV (trochelear) dysfunction?
1) affected eye deviates superiorly and outwards
2) vertical diplopia (especially noticeable when looking down e.g. reading or walking downstairs)
If clopidogrel is contraindicated or not tolerated, what should be given for 2ary prevention following stroke?
Aspirin
Driving post TIA?
Can start driving if symptom free after 1 month - no need to inform the DVLA
