Neuro Flashcards
Which gene is a risk factor for Parkinson’s?
LRRK2
Which area of the brain is affected in Parkinson’s?
Pars compacta of the substantia nigra
What non-specific and non-motor features of Parkinson’s may develop before onset of disease
- Anosmia
- Constipation
- Depression/anxiety
- Micrographia
- Quiet speech
What are the triad of symptoms of Parkinson’s?
- Bradykinesia (decreased rate and amplitude of repetitive movement)
- Resting tremor
- Rigidity
What are the features of tremor seen in PD?
- Intention tremor (worse when reaching for objects)
- Better when distracted with tasks in other hand
- Can also improve on voluntary movement
- Usually asymmetrical
What is the 1st line treatment of PD?
Levodopa if quality of life is impaired
What considerations must you make when prescribing levodopa?
Prescribe it with a dopa decarboxylase inhibitor such as benserazide or carbidopa to minimise nausea and hypotension
What other class of drugs (give examples) is used in combination with levodopa?
Dopamine agonists
-ropinirole, rotigotine
Side effects of ropinirole/rotigotine?
Impulse control disorders
Mode of action of MOAB inhibitor and give examples
Reduces dopamine catbolism in brain
-selegiline, rasagiline
When is use of amantadine indicated?
Helps dyskinesia in advanced PD
Which drugs can cause a worsening of parkinsonim?
Haloperidol/chlorpromazine
Metoclopramide
Name the 4 types of Parkinson plus syndromes and describe their features
All have features of Parkinsonism (bradykinesia, hypertonia, resting tremor)
- Progressive supranuclear palsy - Vertical gaze palsy
- Multiple system atrophy - Early autonomic clinical features (postural hypotension, incontinence, impotence)
- Cortico-basal degeneration - Spontaneous activity in affected limb/akinetic rigidity of limb
- Lewy-body dementia - Fluctuation in cognitive impairment, visual hallucinations
Mode of inheritance of Huntington’s?
- Autosomal dominant
- Trinucleotide repeat disorder (CAG)
- Anticipation
What movement disorders are seen in Huntington’s?
- Chorea
- Eye movement disorder
- Dysarthria
- Dysphagia
What mutation is seen in muscle dystrophy?
Trinucleotide CTG repeat in the DMPK gene
What is myotonic dystrophy?
Disease of abnormal muscle contraction which results in weakness of muscles as well as inability for muscles to relax after contraction
Features of myotonic dystrophy?
- Progresive distal muscle weakness
- Ptosis
- Weakness and thinning of face and sternocleidomastoid
- Respiratory weakness
- Myotonia
Pathophysiology of Duchenne MD?
X-linked recessive disorder. Lack of dystrophin
How does Becker’s MD differ from DMD?
Less severe lack of dystrophin and weakness only becomes apparent in adults
Clinical features of DMD?
- Gower’s sign
- Difficulty running and rising to feet leads to falls
- Calf pseudohypertrophy and proximal muscle weakness
Pathophysiology of Charcot Marie Tooth?
Autosomal dominant disease causing dysfunction in myelin/axons of peripheral motor and sensory nerves
Features of CMT?
- Pes cavus
- Distal muscle wasting (champagne bottle legs)
- Foot drop due to weakness of lower legs
- Hand weakness
- Peripheral sensory loss
- Reduced tone and reflexes
Features of essential tremor?
- Fine tremor
- Symmetrical
- Worsens with voluntary movement, tiredness, stress, after caffeine
- Better with alcohol
Which drugs can help essential tremor?
- Beta blockers (propranolol)
- Alcohol
- Primidone
What movement disorders can antipsychotics cause?
- Dystonia (oculogyric crisis, torticollis)
- Tardive dyskinesia
- Akathisia
- Parkinsonism
CN 3 palsy is associated with which circulatory abnormality?
Aneurysm of posterior communicating artery
Features of MCA stroke in the dominant hemisphere?
- Global aphasia
- Contralateral sensorimotor loss on face, upper limb and trunk
- Homonymous hemianopia
- Dysarthria, dysphagia
Features of MCA stroke in non-dominant hemisphere?
- Neglect syndrome
- Contralateral sensorimotor loss on face, upper limb, trunk
- Homonymous hemianopia
- Dysarthria, dysphagia
Features of ACA stroke?
- Contralateral sensorimotor loss below the waist
- Urinary incontinence
- Personality defects
- Split brain syndrome
Features of PCA stroke?
- Contralateral homonymous hemianopia with macular sparing
- Reading and writing deficit
- Impaired memory
Features of PICA stroke?
Causes Wallenberg syndrome:
- Ipsilateral Horner syndrome
- Ipsilateral sensory deficits in pain and temp in face
- Ipsilateral cerebellar ataxia
- Contralateral sensory deficits in pain and temp in rest of body
- Contralateral vertigo, nystagmus, N&V, diplopia
- Contralateral loss of gag reflex, dysphagia, dysphonia
Which structures are affected in Wallenberg syndrome?
- Ipsilateral descending sympathetic fibres
- Ipsilateral CN V nucleus
- Ipsilateral lateral medulla
- Contralateral spinothalamic tract
- Contralateral CN VIII nucleus
- Contralateral CN IX and X nucleus
What would result from damage to the frontal cortex?
- Personality changes
- Deficit in executive function
- Poor working memory
- Disinhibition and impulsiveness
- Apathy
How is the GCS scored?
Eyes: 4 - spontaneous eye opening 3 - opens eyes to sound 2 - opens eyes to pain 1 - none
Verbal: 5 - orientated to time, person, place 4 - speaks, but confused and not completely coherent 3 - speaks some words 2 - minimal sounds 1 - none
Motor: 6 - follows commands 5 - localises to pain 4 - flexes past midline to pain 3 - abnormal flexion posturing 2 - abnormal extension posturing 1 - none
Extradural haemorrhage is usually caused by rupture of which artery?
Middle meningeal artery
What does CT show for extradural haemorrhage?
Hyperdense, biconcave lens shape that does not cross suture lines
How do acute bleeds and chronic bleeds differ on CT scan?
Acute bleeds appear brighter as they are more dense due to higher iron content
1st line investigation for subarachnoid haemorrhage? Positive scan shows what?
CT scan
+ive scan shows 5 point star shape
What investigation do you do if CT scan is negative for SAH? What do you test for?
Do a lumbar puncture. Look for elevated RBC and xanthochromia. Xanthochromia shows 12 hours later
Why do you test for xanthochromia in CSF?
It is caused by bilirubin from haemolysis in the CSF leading to a yellow appearance
What is the role of calcium channel blockers after SAH surgery?
Prevents vasospasm-induced cerebral ischaemia to optimise cerebral perfusion
Difference between CMT1 and CMT2?
Charcot Marie Tooth 1 is demyelinating. CMT2 is axonal
CSF findings consistent with MS?
oligoclonal bands
Pre-ganglionic causes of Horners
Pancoast tumour
Thyroidectomy
Trauma
Central causes of Horners
Stroke, syringomyelia, MS
Post-ganglionic causes of Horners
Carotid artery dissection, carotid aneurysm, cavernous sinus thrombosis
How to differentiate between pre, post and central causes of Horners?
Central = anhydrosis of face and trunk
Pre-ganglionic = anhydrosis of face
Post-ganglionic = no anhydrosis
Features of cerebellar syndrome?
DANISH: Dysdiadochokinesia Ataxia Nystagmus Intention tremor Slurred speech Hypotonia
Difference between Horners and CN 3 palsy?
Horner is a disruption of sympathetic innervation - there will be miosis and anhydrosis
CN 3 palsy results in unopposed sympathetic action leading to dilated pupil as well as a down and out appearance
Triggers of migraine?
Stress
Bright light
Strong smells
Foods (chocolate, alcohol, caffeine)
How to treat migraines?
- Paracetamol and NSAIDs to treat pain
- Triptans as soon as migraine starts
- Antiemetics if needed
How do triptans work?
- 5HT (serotonin) receptor agonists
- Cause vasoconstriction of smooth muscle
- Inhibit activation of pain receptors
- Reduce CNS neuronal activity
Side effects of triptan use?
Tight chest and throat
What is given as migraine prophylaxis 1st line? 2nd line? Off-license?
1st: Propranolol
2nd: Topiramate
Off-license: Amitriptyline
Pain character and distribution for trigeminal neuralgia?
Shooting, electric type pain in jaw, teeth, gums, face that lasts for a few seconds to 2 minutes
Treatment for trigeminal neuralgia?
Carbamazepine
Pain character and distribution for cluster headache?
Severe and unbearable pain usually around eye.
3-4 attacks a day for a number of weeks then years of pain free before returning
Acute treatment for cluster headache?
Sumatriptan and 100% high flow oxygen
Prophylaxis for cluster headache?
Verapamil or lithium
How long does someone have to be taking analgesia for them to be classed as a medication overuse headache?
Taking analgesia 2/3x a week
or
> 10 days in a month
Features of raised ICP?
- Headache
- Vomiting
- Altered consciousness
- Papilloedema
- Cushing’s triad (hypertension, bradycardia, irregular breathing)
Management of raised ICP?
- IV mannitol as osmotic diuretic
- Controlled hyperventilation
- CSF drain
What role does controlled hyperventilation have on treatment of raised ICP?
Reduces CO2 so vasoconstriction of cerebral arteries and reduces ICP. Needs to be controlled as you are reducing blood flow to an ischaemic brain
What kind of demographic is idiopathic intracranial hypertension seen in ?
Young, overweight females
Management of IIH?
Weight loss
Acetazolamide
Topiramate
Romberg test findings in cerebellar disease?
Romberg test is negative
Features of absence seizure?
Loss of awareness and vacant expression for less than 10s
What can provoke an absence seizure?
Hyperventilation/stress
Feature of focal seizures localised to:
- Temporal lobe
- Frontal lobe
- Occipital lobe
- Parietal lobe
- Feelings of déjà vu, olfactory/gustatory/auditory hallucination, gastric rising, automatisms
- Jacksonian march, posturing, head/leg movements
- Floaters and flashes
- Paresthesia
Treatment of focal seizure?
Carbamazepine generally 1st line. Lamotrigine can be given
What must be tried before IV phenytoin is used for termination of epilepsy?
2 doses of buccal midazolam/rectal diazepam/IV lozapem
Which anti-epileptic should be given if pregnant and having generalised seizures?
Lamotrigine
Side effects of sodium valproate?
- Teratogenic
- Weight gain
- LFT derangement (hepatitis)
- Hair thinning/alopecia
- Tremor
- Thrombocytopaenia
Side effects of carbamazepine?
- SIADH (hyponatremia)
- SJS
- Dizziness/ataxia
- Nystagmus
- Leucopaenia/agranulocytosis
- Diplopia
Side effects of lamotrigine?
- SJS
- Lymphopaenia
Side effects of phenytoin?
- Gingival hyperplasia
- Peripheral neuropathy
- Lymphadenopathy
- Acne, hirsutism
Side effects of topiramate?
- Weight loss
- Renal stones
- Glaucoma
- Memory loss
Rules on driving with epilepsy?
- Patients cannot drive for 6 months after 1st seizure.
- For patients with established epilepsy, they must be fit free for 12 months
What is the pathological hallmark of MND?
TDP-43 and FUS proteins seen in axons
UMN lesion features?
- Weakness
- No/slight muscle wasting
- Hyperreflexia
- Hypertonia
- No fasciculations
- Babinski positive
LMN lesion features?
- Weakness/flaccid paralysis
- Muscle wasting
- Hyporeflexia
- Fasciculations
- Hypotonia
Features of amyotrophic lateral sclerosis?
Involvement of UMN and LMN signs of one limb that spreads to other limbs and trunk
(Typically UMN signs in legs and LMN signs in arms)
Features of progressive muscular atrophy
- LMN signs only
- Affects distal muscles then proximal
- Starts in one limb then spreads to affect other spinal segments
Features of primary lateral sclerosis?
- UMN signs only
- Slowly progressive tetraparesis
Features of progressive bulbar palsy?
- Tongue fasciculation with slow, stiff tongue movements
- Dysfunction of CN nuclei 9-12
- Dysarthria, dysphagia, choking
- Loss of gag reflex
Features of progressive pseudobulbar palsy?
- Dysarthria, dysphagia, emotional lability
- Brisk jaw jerk reflex
- Hot potato speech
General features of MND?
- Fasciculation
- Absence of sensory symptoms
- Mixture of UMN and LMN signs
- Wasting of small hand muscles/tibialis anterior
- Does not affect eye muscles
- No cerebellar signs
Management of MND?
- Riluzole
- Respiratory support
Mechanism of action of riluzole?
Glutamate receptor antagonist
Classic demographic of MS patient?
White, 30yrs, woman
What is MS?
Chronic, autoimmune, T-cell mediated inflammatory disorder of white matter of CNS
What is the cardinal feature of MS?
Plaques of demyelination found in brain and spinal cord
What feature of MS is crucial for diagnosis?
Dissemination in time and space
Common features of MS?
- Optic neuritis
- Brainstem demyelination (diplopia, vertigo, dysarthria, dysphagia)
- Spinal cord lesions (paraparesis, difficulty walking)
Other symptoms of MS?
- Visual change
- Sensory change
- Clumsy hands
- Ataxia
- Urinary urgency/frequency
- Fatigue
- Spasticity
- Depression
What is the most common pattern of MS?
relapsing-remitting
Describe disease course of secondary progressive MS
Initially relapsing-remitting but then sudden decline without remission
Describe disease course of primary progressive MS
Worsening MS with no periods of relapse or remission
Describe disease course of relapsing progressive MS
Disease getting worse overall but has periods of severe and worsening attacks
Which investigation is definitive in MS?
MRI brain shows plaques and scars
What does lumbar puncture show in MS?
Oligoclonal bands against myelin
What medication can be given for MS? What does it do?
Steroids can help alleviate acute attacks
Beta-interferon or Natalizumab can modify course of inflammatory relapsing-remitting MS
Treatment of transverse myelitis?
High dose steroids/immunosuppression
Antimicrobials if infective cause
Triad of symptoms seen in meningitis?
Headache
Fever
Neck stiffness
Other symptoms of meningitis?
- Photophobia
- Vomiting
- Irritability
CSF appearance in bacterial meningitis?
- Cloudy
- Low glucose (<50% of plasma glucose)
- High protein
- High WCC (polymorphs)
CSF appearance in viral meningitis?
- Clear/cloudy
- 60-80% of plasma glucose
- Proteins normal slightly raised
- Lymphocytes
How does tuberculous meningitis CSF differ from bacterial meningitis CSF?
- Appearance has fibrin web
- Has lymphocytes
Empirical antibiotics given in meningitis?
Cefotaxime
Benzylpenicillin if meningococcus sensitivity confirmed
Complications of meningitis?
- Sensorineural hearing loss
- Seizure
- Hydrocephalus
- Focal neurological deficit
- Sepsis
What drug should be given with 1st dose of antibiotics to reduce neurological complications of meningitis?
Dexamethasone
Most common causative organism of encephalitis?
HSV1
Features of encephalitis?
- Meningism
- Focal neurological deficits
- Seizures
- Vomiting
- Reduced consciousness
- Personality and behavioural change
Carpal tunnel syndrome is more common in those with which diseases?
- Diabetes
- Hypothyroid
- 3rd trimester pregnancy
- RA
Sensory distribution of median nerve?
Lateral 3.5 fingers in the palmar hand
Top half of fingers 2, 3, half of 4 in the dorsal hand
Describe Tinel and Phalen test
(Tapping)Tinnel: tap nerve in the carpal tunnel
(Phlexing)Phalen: hold the wrist in flexion
Both tests cause pain and tingling if positive
Which nerve is affected in cubital tunnel syndrome?
Ulnar
What hand signs are seen in cubital tunnel syndrome?
- Claw hand
- Wasting of interossei and hypothenar muscles
- Wasting of medial 2 lumbricals
- Sensory loss over medial 1.5 fingers
What structure is damaged with spiral fracture of humerus?
Radial nerve - Wrist drop
Signs of radial nerve palsy?
- Wrist drop
- Weakness of flexion (brachioradialis) and finger extension
- Sensory loss to dorsum of 1st and 2nd metacarpals
What is caused by meralgia paraesthetica?
Compression of lateral cutaneous nerve of thigh
Signs of common peroneal nerve palsy?
- Foot drop (deep peroneal nerve) and weak ankle eversion (superficial peroneal nerve)
- Numbness over anterolateral border of dorsum of foot and lateral calf
Common prodrome of Guillain-Barre Syndrome?
Gastroenteritis
What are the causes of GBS?
- Campylobacter jejuni
- CMV
What kind of disease is GBS?
Autoimmune demyelinating disease of the PNS causing symmetrical ascending weakness
Symptoms of GBS?
- Leg/back pain
- Ascending, symmetrical weakness in limbs
- Reflexes reduced/absent
- Mild sensory impairment
- Respiratory failure
- Diplopia, facial nerve palsy, oropharyngeal weakness
- Urinary retention
What is the classic finding in lumbar puncture of GBS?
Raised proteins with normal WCC
What do nerve conduction studies show in GBS?
Decreased motor nerve conduction velocity due to demyelination
What is important to be monitored in GBS and how is this done?
Respiratory function by FVC
What is given to reduce the severity and duration of paralysis in GBS?
IV immunoglobulins
What is Miller Fisher syndrome?
A variant of GBS associated with ophthalmoplegia, areflexia and ataxia. Eye muscles are typically affected first
(descending paralysis)
Which antibodies are seen in Miller Fisher syndome?
Anti-GQ1b
What deficits are seen in syringomyelia and how is this distributed?
Bilateral loss of pain, temperature sensation and motor weakness
Distributed in cape-like pattern (neck, shoulders, arms)
What is the thrombolysis protocol of ischaemic stroke?
Thrombolysis with alteplase (tPA) only if:
- Haemorrhagic stroke has been excluded
- Administration is within 4.5hrs of symptoms
What is the thrombectomy protocol of ischaemic stroke?
Can only be done if:
- Haemorrhagic stroke has been excluded
- Done within 6hrs of symptoms
What is the medical management of ischaemic stroke?
- 300mg aspirin for 14 days as soon as haemorrhagic stroke has been excluded
- Statin if cholesterol is >3.5mmol/L
- Clopidogrel 75mg after 14 days
What 3 features are seen in an anterior circulation infarct?
- Contralateral hemiparesis
- Homonymous hemianopia
- High cognitive dysfunction such as dysphasia
What is a TIA?
Transient, sudden loss of neurological function that has complete recovery
What is the risk of full stroke with someone who has had a TIA?
10% risk of stroke within 90 days
What is the management of TIA in the community?
- 300mg aspirin
- Refer to TIA clinic ASAP with carotid imaging within 24 hours
What is the management of TIA in the hospital?
- Aspirin 300mg stat then 75mg daily
- Full imaging screen: CT head, ECG, CTA/Doppler
- Refer to TIA clinic
Management of facial paralysis?
- Otoscopy to check for Ramsay Hunt
- Prednisolone
Treatment of Ramsay Hunt syndrome?
Oral aciclovir
Prednisolone
Lesion in optic nerve causes which visual field defect?
Monocular vision loss
Lesion in optic tract causes which visual field defect?
Contralateral homonymous hemianopia
Lesion in superior fibres of optic radiation of parietal lobe?
Contralateral inferior quadrantianopia
Lesion in the inferior fibres of optic radiation of temporal lobe?
Contralateral superior quadrantianopia
Lesion in occipital lobe causes which visual field defect?
Contralateral homonymous hemianopia with macular sparing
What is the pathophysiology of myasthenia gravis?
Antibodies against ACh receptors lead to insufficient functioning at the NMJ
What happens in myasthenic crisis?
Respiratory muscles become weak leading to respiratory failure. Consider ventilation if FVC falls below 15ml/kg
Which cancer is associated with myasthenia gravis? What imaging is required during investigation?
Thymoma - CT chest required
What is seen on EMG in myasthenia gravis?
Repetitive stimulation of a nerve will show a characteristic decrement in muscle action potential
Which antibodies are hallmark for myasthenia gravis?
Anti-AChR
Which other antibodies are also seen in MG?
Anti-MuSK
Pattern of weakness in those with anti-MuSK MG?
Weakness of face, neck and bulbar muscles
1st line treatment of MG? Drug class?
Pyridostigmine - acetylcholinesterase inhibitor
Which antibodies characterises Lambert Eaton syndrome?
Antibodies against voltage gated calcium channels (anti VGCC) in the PNS
What cancer is associated with LEMS?
Small cell lung cancer
What is seen on EMG with LEMS?
Repetitive stimulation shows incremental response
Features of LEMS?
Proximal limb weakness affecting lower limbs and absent reflexes
These get better after repeated muscle contraction
Treatment of LEMS?
Immunosuppression with prednisolone
Features of normal pressure hydrocephalus?
Urinary incontinence
Dementia
Gait disorder/apraxia
“Wet, weird, wobbly”
What causes normal pressure hydrocephlaus?
Enlarged lateral ventricles in elderly patients
What kind of seizure does carbamazepine not have a role in treatment?
Absence seizures
Myoclonic seizures
What is the difference between Wernicke’s aphasia and conduction aphasia?
Both have impaired repetition of words but comprehension is preserved in conduction.
“Wernicke = What? (no comprehension)”
Which drugs can be given to help spasticity in MS?
Baclofen or gabapentin
Stroke affecting which areas of the brain lead to expressive, receptive and conduction aphasias?
Expressive = Broca = inferior frontal gyrus Receptive = Wernicke = superior temporal gyrus Conduction = arcuate fasciculus
Features of Weber syndrome? Where is the location of stroke in this syndrome?
- Ipsilateral CN 3 palsy
- Contralateral weakness on whole side of body
- Stroke in midbrain
What is pituitary apoplexy, most common cause and how is it treated?
- Bleeding of the pituitary
- Most commonly caused by bleeding of pituitary tumour
- Treat with steroids
Which class of drugs worsen MG?
beta blockers
What can cause a bitemporal hemianopia with superior quadrants more affected? Inferior quadrants more affected?
Superior more affected: pituitary macroadenoma
Inferior more affected: craniopharyngioma
What is the MRC muscle power grading system?
Grade 5: normal strength
Grade 4: movement against resistance with reduced power
Grade 3: cannot move against resistance, can against gravity
Grade 2: can move with gravity eliminated
Grade 1: twitches and trace contractions
Grade 0: none
When should carotid endarterectomy be done?
High grade symptomatic carotid stenosis with >70% narrowing
CSF appearance in encephalitis?
- Lymphocytes (raised WCC)
- Normal glucose
- Slightly raised protein
How does CSF appear in T1 vs T2 weighted MRI?
T1: CSF is dark
T2: CSF is light
Which mutation is seen in cases of familial MND?
SOD1
