Neurology Flashcards
What is a TIA
Transient neurological dysfunction secondary to ischaemia without infarction
What is a crescendo TIA?
2 or more TIAs in one week
List some stroke RF
CVD - angina, MI, PVD Previous stroke/TIA AF Carotid artery disease HTN DM Smoking Vasculitis Thrombophilia COCP
Describe the management of stroke
Head CT to exclude haemorrhage
Exclude hypoglycaemia
Do not try to lower BP - risk of hypoperfusion
Aspirin 300mg STAT and continued for 2 weeks
Thrombolysis with Alteplase <4.5hrs symptom onset
Thrombectomy <24hrs
Describe the secondary prevention of stroke
Treat modifiable RF
Clopidogrel 75mg OD (or dipyridamole 200mg BD)
Atorvastatin 80mg
Carotid endarterectomy fi stenosis
What is a cerebral venous sinus thrombosis
Blood clot in veins that drain the brain resulting in venous congestion and tissue hypoxia
What are the two types of haemorrhage
Intracerebral - bleeding into the brain secondary to ruptured vessel - interventricular or intraparenchymal
Subarachnoid haemorrhage - bleeding outside the brain between pia mater and arachnoid mater
Describe a total anterior circulation stroke
All 3:
Unilateral weakness (and/or sensory deficit)
Homonymous hemianopia
Higher cerebral dysfunction
Describe partial anterior circulation stroke
2 of the TACS
Describe posterior circulation stroke
Cranial nerve palsy with a contralateral motor/sensory deficit
Bilateral motor or sensory deficit
Conjugate eye movement disorder
Isolated homonymous hemianopia
Describe lacunar stroke
Subcortical stroke that occurs secondary to small vessel disease
No loss of higher cerebral function
Pure motor
Pure sensory
Sensori-motor
Ataxic hemiparesis
List the layers under the skull
Dura mater
Arachnoid mater
Pia mater
List some risk factors of intracranial bleeds
Head injury HTN Aneurysms Ischaemic stroke Brain tumour Anticoagulants
Describe the presentation of an intracerebral bleed
Sudden onset headache Seizures Weakness Vomiting Reduced consciousness Sudden onset neurological symptoms
Describe the glasgow coma scale
Max = 15 Min = 3
Eyes
- spontaenous = 4
- speech = 3
- Pain = 2
- None = 1
Verbal response
- Orientated = 5
- Confused conversation = 4
- Inappropriate words = 3
- Incomprehensible sounds = 2
- None = 1
Motor response
- obeys commands = 6
- Localises pain = 5
- Normal flexion = 4
- Abnormal flexion = 3
- Extends = 2
- None = 1
Describe subdural haemorrhage
Rupture of bridging veins
Between dura and arachnoid mater
Crescent shape on CT
Not limited by cranial sutures - cross over suture lines
More frequent in eldely and alcoholic patients
Describe extradural haemorrhage
Rupture of the middle meningeal artery in the temporo-parietal region - can be associated with fracture of the temporal bone
Between the skull and dura mater
Bi-convex shape and are limited by cranial sutures (do not cross the suture lines)
Young patient with traumatic head injury and ongoing headache
Brief period of improved neurological symptoms and consciousness followed by a rapid decline over hours as the haematoma gets large enough to compress the intracranial contents
Describe intracerebral haemorrhage
Bleeding into brain tissue
Can occur spontaneously or as the result of bleeding into an ischaemic infarct or tumour or rupture of aneurysm
Describe a subarachnoid haemorrhage
Bleeding into the subarachnoid space, where the CSF is located between the pia mater and arachnoid membrane - usually the result of cerebral aneurysm
Sudden onset occipital headache that occurs after strenuous activity such as weight lifting or sex. Thunderclap headache
Associated with cocaine and sickle cell disease
Describe the management of intracerebral bleeds
Immediate head CT
Check FBC and clotting
Admit to specialist stroke unit
Discuss with neurosurgical centre to consider surgical treatment
Consider intubation, ventilation and ICU care if they have reduced consciousness
Correct severe hypertension but avoid hypotension
Correct any clotting abnormality
LP 12hrs after onset of symptoms in suspected subarachnoid haemorrhage and normal non contrast CT head
What drug is given to people with subarachnoid haemorrhage which prevents vasospasm?
Nimodipine (21 day course - dihydropyridine calcium channel blocker)
What is a common consequence of subarachnoid haemorrhage
Syndrome of inappropriate ADH (hyponatremia)
List the risk factors of subarachnoid haemorrhage
HTN Smoking Excessive alcohol consumption Cocaine use FH Black and female patients Age 45-70 Sickle cell anaemia Connective tissue disorders - Marfans syndrome or Ehlers Danlos Neurofibromatosis Autosomal dominant polycystic kidney disease
List the investigations in subarachnoid haemorrhage
CT head is first line - blood in subarachnoid space has hyper attenuation
LP is used to collect a sample of CSF if CT head negative - red cell count will be raised and xanthochromia (yellow colour of CSF caused by bilirubin)
Angiography - used to confirm the source of bleeding
Describe the management of subarachnoid haemorrhage
Specialist neurosurgical unit
Surgical intervention - coiling, clipping
Nimodipine - prevent vasospasm
Lumbar puncture or insertion of shunt if hydrocephalus
Antiepileptic medications - seziures
Describe the presentation of pituitary apoplexy
Sudden onset headache
Visual field defect
Evidence of pituitary insufficiency
What is multiple sclerosis
Chronic and progressive demyelination of myelinated neurones in the CNS - autoimmune condition
Who does MS affect
More commonly women <50 yo
How does pregnancy and post partum affect MS symptoms
Improves them
Name the two types of myelin
Schwann cells - PNS
Oligodendrocytes - CNS
Which type of myelin does MS typically affect
CNS - oligodendrocytes
What is a characteristic feature of MS lesions?
Vary in their location over time - different nerves are affected at different points in time
Disseminated in time and space
What are the causes of MS
Combination of Multiple genes Epstein Barr virus Low vit D Smoking Obesity
What causes MS symptoms to resolve in early disease?
Re-myelination
Describe symptom progression in the first presentation of MS
Progress over more than 24hrs and last days to weeks then improve
List some ways MS can present
Optic neuritis
Eye movement abnormalities
What occurs in a 6th CN palsy
Internuclear ophthalmoplegia - eyes do not move together
Conjugate lateral gaze disorder - when gazing to the direction of the affected eye, the affected eye will not be able to abduct
Double vision
Describe optic neuritis
Loss of vision in one eye Central scotoma - enlarged blind spot Pain on eye movement Impaired colour vision Relative afferent pupillary defect
What is Lhermitte’s sign
Electric shock sensation that travels down the spine and into the limbs when flexing the neck - indicates disease in the cervical spinal cord and dorsal column
Caused by stretching the demyelinated dorsal column
Give some examples of focal weakness in MS
Bells palsy
Horner’s syndrome
Limb paralysis
Incontinence
List some focal sensory symptoms in MS
Trigeminal neuralgia
Numbness
Paraesthesia (pins and needles)
Describe ataxia in MS
Problem with coordination
Sensory ataxia - loss of proprioceptive sense
Cerebellar ataxia - problem coordinating movement
How do you test for sensory ataxia
Romberg’s test
What is psuedoathetosis
Writhing movement due to loss of proprioception - sensory ataxia
What is meant by clinically isolated syndrome in MS
MS cannot be diagnosed on one episode as the lesions have not be disseminated in time and space
Patients may never have another episode or develop MS - of lesions are seen on MRI then more likely to progress to MS
Describe relapsing-remitting MS
Most common pattern at initial diagnosis
Characterised by episodes of disease and neurological symptoms followed by recovery
Active - new symptoms are developing or new lesions are on MRI
Worsening - overall worsening of disability over time
Describe secondary progressive MS
Where there was relapsing remitting at first but now there is progressive worsening of symptoms with incomplete remissions
Symptoms have become more and more permanent
Can be classified based on active and/or progressing
Describe primary progressive MS
Worsening of disease and symptoms from disease onset without remissions and relapses
How is MS diagnosed
MRI scan - typical lesion
Lumbar puncture - oligoclonal bands in CSF
List some conditions which cause optic neuritis
Sarcoidosis SLE DM Syphilis Measles Mumps Lyme disease
How should optic neuritis be managed
Ophthalmology urgent review
2-6 weeks for recovery
Steroids
How is MS managed?
MDT
Disease modifying drugs
Biologic therapy
Relapses treated with Methylprednisolone - 500mg PO OD for 5 days, 1g IV daily for 3-5days when oral treatments failed previously or where relapses are severe
Exercise
Neuropathic pain - amitriptyline and gabapentin
Depression - SSRIs
Urge incontinence - anticholinergic medications - tolterodine and oxybutynin (worsen cognitive function)
Spasticity - baclofen, gabapentin and physio
What are motor neurone diseases
Umbrella term for number of diagnoses
Progressive and ultimately fatal condition where the motor neurones stop functioning
No effect on sensory symptoms and patients should not experience any sensory symptoms
What does progressive bulbar palsy affect
Affects the muscles of talking and swallowing
List some MNDs
Amyotrophic lateral sclerosis
Progressive bulbar palsy
Progressive muscular atrophy
Primary lateral sclerosis
Describe the neurological signs of MND
Bother upper and lower motor neurones affected
Sensory neurones are spared
What causes MND
Exact cause is unknown
Genetics (10%) - FH
Smoking
Exposure to heavy metals
Pesticides
List the signs of an upper motor neurone lesion
Increased tone
Upgoing plantars
Brisk reflexes
List the signs of a lower motor neurone lesion
Muscle wasting
Reduced tone
Fasciculation (twitches in the muscles)
Reduced reflexes
What drugs can be used to slow the progression of MND
Riluzole - extends survival by few months
Edaravone - used in US
NIV - support with breathing at night and improves QOL
Give the classic triad of Parkinson’s disease
Resting tremor
Rigidity
Bradykinesia
Describe the physiology of Parkinson’s disease
Basal ganglia in the middle of the brain are responsible for coordinating habitual movements such as walking, looking around, controlling voluntary movements and learning specific movement patterns
The substantia nigra (part of the basal ganglia) produces dopamine which is essential for the correct functioning of the basal ganglia but in PD there is a gradual and progressive fall in the production of dopamine
Describe the presentation of the tremor in Parkinson’s disease
4-6Hz - meaning it occurs 4-6 times a second
Pill-rolling tremor - fingertips and thumb
More pronounced when resting and improves on voluntary
Tremor is worsened if the patient is distracted - ask them to mime painting the fence - exaggerate the tremor
Describe the rigidity in Parkinson’s disease
Rigidity is a resistance to passive movement of a joint
If you take their hand and passively flex and extend their arm at the elbow, you will feel a tension in their arms that gives way to movement in small increments.
Describe signs of bradykinesia in Parkinson disease
Small handwriting
Shuffling gait
Difficulty initiating movement
Difficulty in turning around when standing, having to take lots of little steps
Reduced facial movements and facial expressions
What other features affect people with Parkinson’s disease
Depression Sleep disturbance and insomnia Loss of sense of smell (anosmia) Postural instability Cognitive impairment and memory problems
Describe the difference between benign and essential tremor
Parkinson’s tremor - Asymmetrical, 4-6 Hz, worse at rest, improves with intentional movement, other Parkinson’s features, no change with alcohol
Benign essential tremor - Symmetrical, fine tremor, 5-8Hz, improves at rest, worse with intentional movement, worse with caffeine, tiredness and stress, no other Parkinson’s features, improves with alcohol, not present at sleep
What is multiple system atrophy
Where neurones of multiple systems in brain degenerates.
Affects the basal ganglia as well as other areas - the degeneration in basal ganglia leads to Parkinson’s presentation. Degeneration in other areas lead to autonomic dysfunction and cerebellar dysfunction (ataxia)
List some of the autonomic dsyfunction
Postural hypotension
Constipation
Abnormal sweating
Sexual dysfunction
Describe dementia with Lewy bodies
Dementia associated with features of Parkinsonism - visual hallucinations, delusions, disorders of REM sleep and fluctuating consciousness
How is Parkinson’s disease diagnosed?
Clinical symptoms and examination
How is Parkinson’s disease treated?
On - medication working
Off - medication wear off
Levodopa - synthetic dopamine give PO to boost their own dopamine levels.
Usually combined with a peripheral decarboxylase inhibitors (drug that stops levodopa being broken down in the body before it gets the chance to enter the brain)
Co-careldopa (levodopa and carbidopa)
Co-benyldopa (levodopa and benserazide)
COMT inhibitors - Entacapone - inhibits the COMT enzyme which usually metabolises levodopa in the body and brain. Taken with the levodopa to slow the breakdown of levodopa and extend its effective duration
Dopamine agonists (cabergoline, pergolide, bromocryptine) - mimic dopamine in the basal ganglia and stimulate the dopamine receptors. Less effective than levodopa but used to delay the use of levodopa and the dose of levodopa required.
Monoamine oxidase B inhibitors - enzymes break down neurotransmitters such as dopamine, serotonin and adrenaline. More specific to dopamine and does not act on serotonin or adrenalin. These medications block the enzyme and increase circulating dopamine Used to delay starting levodopa - selegilline and rasagiline
What happens to Levodopa effectiveness over time
Becomes less effective
What is the main side effect of levodopa
When dopamine levels are too high - this causes dyskinesia (excessive motor activity)
- dystonia - excessive muscle contraction leads to excessive movement and abnormal posture
- Chorea - abnormal involuntary movements that can be jerking and random
- Athetosis - involuntary twisting and writhing movements of the fingers, hands and feet
What is a side effect of the dopamine agonists
Pulmonary fibrosis with prolonged use
What is the differential diagnosis for a benign essential tremor
Parkinson's disease MS Huntington's chorea Hyperthyroidism Fever Medication - antipsychotics and salbutamol overuse
Describe the management of benign essential tremor
No definitive treatment
Medication can improve symptom - propranolol (non-selective beta blocker) and primidone (barbiturate anti-epileptic)
What is epilepsy
An umbrella term for a condition where there is a tendency to have seizures
What are seizures
Transient episodes of abnormal electrical activity in the brain
What investigations should be done for epilepsy
EEG
MRI brain
ECG
Describe a tonic-clonic seizure
Loss of consciousness
Tonic phase before clonic phase
Tonic phase is muscle stiffening
Clonic phase is muscle jerking
May be associated with incontinence, tongue biting, groans and irregular breathing
Post ictal period - confused, drowsy, irritable or depressed
Describe the management of tonic clonic seizures
1st line - sodium valproate
2nd line - lamotrigine or carbamazepine
Where do focal seizures originate?
Temporal lobe
Describe the presentation of focal seizures
These affect hearing, speech, memory and emotion Hallucinations Memory flashbacks Deja vu Doing strange things on autopilot Post-ictal weakness
How do you treat focal seizures
1st line - carbamazepine or lamotrigine
2nd line - sodium valproate or levetiracetam
Describe absence seizures
Happen in children
Patient becomes blank, stares into space and then abruptly returns to normal
These last 10-20seconds and the patient will not respond in this time
What is the management of absence seizures
Sodium valproate or ethosuximide
Describe atonic seizures
Drop attacks Brief lapses in muscle tone Don't usually last more than 3 mins Begin in childhood Indicative of lennox-gastaut syndrome
Describe the management of atonic seizures
1st line - sodium valproate
2nd line - lamotrigine
Describe myoclonic seizures
Sudden brief muscle contractions - sudden jump
Patient remains awake during the episode
Most often occur in juvenile myoclonic epilepsy
How are myoclonic seizures treated
1st line - sodium valproate
2nd line - lamotrigine, levetiracetam, topiramate
Describe infantile spasms (West syndrome)
Rare disorder - full body spasms
starting in infancy at around 6 months - poor prognosis where 1/3 die before 25 and the rest are seizure free
Treated with prednisolone and vigabatrin
How does sodium valproate work
Increases the activity of GABA
Relaxing effect on the brain
List some side effects of sodium valproate
Teratogenic
Liver damage and hepatitis
Hair loss
Tremor
List some notable side effects of carbamazepine
Agranulocytosis
Aplastic anaemia
Induces P450 enzyme system - drug interactions
List some notable effects of phenytoin
Megaloblastic anaemia
Vit D and folate deficiency
Osteomalacia
List some notable side effects of ethosuximide
Night terrors
Rashes
List some notable side effects of lamotrigine
Stevens - Johnson syndrome or DRESS syndrome
Leukopenia
Define status epilepticus
A seizure lasting >5 mins or >3 seizures in 1 hour
How do you treat status epilepticus
ABCDE approach Secure the airway - NP tube Give high flow O2 Assess cardiac and respiratory function Check blood glucose Gain IV access - cannulate IV lorazepam 4mg, repeat after 5 mins If seizure persists try IV phenytoin and call anaesthetists with view to intubate and ventilate
What is the name of the post-ictal weakness focal epileptic patients get
Todd’s paresis
What type of symptoms do frontal lobe seizures cause
Motor - jerking of the limb
Jacksonian march
What types of symptoms would occur with an occipital lobe seizure
Visual hallucinations
What symptoms would a parietal lobe seizure present with
Paraesthesia
What symptoms do temporal lobe focal seizures present with
Hallucinations Epigastric rising Emotional Automatisms - lip smacking, grabbing and plucking Deja vu Dysphasia
Describe a Jacksonian March
Seizure begins in one part of the body and then spreads over larger area of the brain causing a tonic clonic seizure
Secondary generalisation
When and how can anti-epileptic drugs be stopped
If seizure free for >2yrs and stopped over 2-3months
How can epileptic seizures be differentiated from vasovagal syncope
Vasovagal syncope - no post ictal period and rapid recovery
What is neuropathic pain, give examples of the causes
Abnormal functioning of the sensory nerves delivering abnormal and painful signals to the brain
Burning, tingling, pins and needles, electric shocks, loss of sensation to touch over the affected area
Post herpetic neuralgia from shingles in the distribution of a dermatome usually on the trunk
Nerve damage from surgery
MS
Diabetic neuralgia
Trigeminal neuralgia
Complex regional pain syndrome (CRPS)
What is the DN4 questionnaire
Used to assess the characteristics of neuropathic pain and the examination of the area
Scored out of 10 and a score >4 indicates neuropathic pain
Which drugs can be tried to relieve neuropathic pain
Amitriptyline
Duloxetine
Pregabalin
Gabapentin
Tramadol - short term flares
Capsaicin cream
Which drug is first line when treating trigeminal neuralgia
Carbamazepine
Describe complex regional pain syndrome
Abnormal nerve functioning - abnormal sensations and neuropathic pain
Often triggered by an injury to that area
Intermittent swelling, change in colour, temperature, flush and abnormal sweating
Describe the path of the facial nerve
Exits the brainstem at the cerebellopontine angle
Passes through the temporal bone and parotid gland
Divides into 5 branches that supply different areas of the face - temporal, zygomatic, buccal, marginal mandibular and cervical
Describe the functions of the facial nerve
Motor - facial expression, stapedius in inner ear and the posterior digastric, stylohyoid and platysma muscles of the neck
Sensory - taste of anterior 2/3 tongue
Parasympathetic - submandibular and sublingual salivary glands and the lacrimal gland
Describe the nerve innervation of the forehead
Each side of the forehead has upper motor neuron innervation by both sides of the brain
Each side of the forehead only has lower motor neuron innervation from one side of the brain
What can be seen in an UMN facial palsy
Forehead sparing
Describe the symptoms of Bells palsy
Forehead affected
Drooping of the eyelid
Exposure of the eye
Loss of the nasolabial fold
List some causes of an UMN facial palsy
Cerebrovascular accident
Tumour
Bilateral - pseudobulbar palsy and MND
List some causes of LMN facial palsy
Bells palsy Ramsay Hunt syndrome Otitis media Malignant otitis externa HIV Lyme disease Diabetes Sarcoidosis Leukaemia MS Guillian Barre syndrome Acoustic neuroma Parotid tumours Cholesteatoma Direct nerve injury Injury during surgery Base of skull fracture
How long does recovery from Bells palsy take?
several weeks - 12 months however some never recover completely (1/3 left with residual weakness)
How is Bells palsy treated
Prednisolone
50mg for 10days
60mg for 5 days followed by a 5 day reducing regime of 10mg a day
Lubricating eye drops
What may happen as a result of Bells palsy
Exposure keratopathy
Describe Ramsay Hunt syndrome
Varicella zoster virus (VZV)
Unilateral LMN facial palsy
Tender vesicular rash in ear canal, pinna, around ear on affected side
The rash can extend to the anterior 2/3 of the tongue and hard palate
How is Ramsay Hunt syndrome treated
Prednisolone
Aciclovir
Lubricating eye drops
What happens to perception of sound in an UMN facial nerve palsy
Hyperacusis - hypersensitivity to sound
Paralysis of stapedius
When should facial nerve palsies be referred to ENT or neurology
Worsening or new neurological findings
Red flag features of cancer
No signs of improvement after 3 weeks of treatment
Symptoms of aberrant reinnervation 5 months or more after original onset
Unclear diagnosis
Describe the symptoms of a brain tumour
Focal neurological lesion
Signs of raised ICP
Often asymptomatic at the beginning
List some causes of raised intracranial pressure
Brain tumour
Intracranial haemorrhage
Idiopathic intracranial hypertension
Abscesses or infection
Describe the presentation of raised intracranial pressure
Headache - constant, nocturnal, worse on waking, coughing, straining or bending forward, vomiting
Altered mental state Visual field defects Seizures - focal Unilateral ptosis Third and sixth nerve palsy Papilloedema
What is Papilloedema
Swelling of the optic disc secondary to raised intracranial pressure
The sheath around the optic nerve is connected with the subarachnoid space - possible for CSF under high pressure to flow into the optic nerve sheath and causes swelling
Describe the fundoscopic changes of Papilloedema
Blurring of the optic disc margin
Elevated optic disc - curve in retinal vessels
Loss of the venous pulsation
Engorged retinal veins
Haemorrhages around optic disc
Paton’s lines - creases in the retina around the optic disc
Which cancers commonly metastasise to the brain
Breast
Lung
Renal cell carcinoma
Melanoma
Describe gliomas
Tumours of glial cells
- Astrocytoma - glioblastoma multiforme
- oligodendroglioma
- Ependymoma
Graded from 1-4 - grade 1 is most benign and grade 4 is most malignant
Describe a meningioma
Tumour of the meninges in the brain and lead to raised ICP and neurological symptoms
Describe pituitary tumours
Benign but if they become large can press on the optic chiasm causing bitemporal hemianopia (loss of the outer half of vision in both eyes
Hypo or hyperpituitarism
- Acromegaly
- Cushing’s syndrome
- Hyperprolactinaemia
- Thyrotoxicosis
Describe acoustic neuroma
Tumour of Schwann cells surrounding the auditory nerve that innervates the inner ear
Occur at the cerebellopontine angle
Usually unilateral, bilateral ones associated with neurofibromatosis type 2
Slow growing but eventually grow large enough to cause symptoms and become dangerous
- Tinnitus
- Hearing loss
- Balance problems
Associated with facial nerve palsy
Describe the treatment of pituitary tumours
Trans-sphenoidal surgery
Radiotherapy
Bromocriptine - block prolactin secreting tumour
Somatostatin analogues - octreotide - block growth hormone secreting tumour
What is Huntington’s chorea
Autosomal dominant progressive deterioration of nervous system
Asymptomatic until symptoms begin age 30-50
Describe the genetic abnormality in Huntington’s chorea
Trinucleotide repeat disorder of HTT gene on chromosome 4
Describe what is meant by anticipation in Huntington’s chorea
Each successive generation, more trinucleotide repeats resulting in earlier onset and increased severity of disease
Describe the presentation of Huntington’s chorea
Begins with cognitive, psychiatric or mood problems
- Chorea - involuntary, abnormal movements
- Eye movement disorders
- Speech difficulties - dysarthria
- Swallowing difficulties
Describe the prognosis of Huntington’s chorea
15-20yrs life expectancy following diagnosis
Death is often due to respiratory disease or suicide
Describe myasthenia gravis
Autoimmune condition
Weakness gets progressively worse with activity and improves with rest
At what age does myasthenia gravis tend to present
<40yo women
>60 men
What type of tumour is linked to myasthenia gravis
Thyoma (tumour of thymus gland)
Describe normal conduction across the neuromuscular junction
Pre-synaptic neurone secretes acetylcholine across the synapse which then binds to post synaptic receptors and stimulates a signal in the muscle and muscle contraction occurs
What happens to neuromuscular junction transmission in myasthenia gravis
Antibodies to the acetylcholine receptor are produced. These bind to the post synaptic membrane and block the receptor. Acetylcholine is prevented from stimulating the post synaptic membrane and prevent muscle contraction
As more receptors are used up during more muscle activity, more become blocked
There is more muscle weakness the more the muscles are used This improves with rest when more receptors are free for use again
Complement system is also activated and this damages the postsynaptic membrane
Antibodies against Muscle specific kinase (MuSK) and antibodies against low density lipoprotein receptor related protein 4 (LRP4) - used to create the ACH receptor. Destruction of these by antibodies leads to inadequate receptors
Describe the presentation of myasthenia
Proximal muscles Diplopia - weak extraocular muscles Ptosis Weak facial muscles Difficulty swallowing Fatigue in the jaw when chewing Slurred speech Progressive weakness with repetitive movement
Symptoms are worse at night time
Describe the examination and investigations for myasthenia gravis
Upward gazing - diplopia on further eye movement test
Repeated blinking will exacerbate ptosis
Repeated abduction of one arm 20 times will result in unilateral weakness when comparing both sides
FVC
Check for thymectomy scar
How is a diagnosis of myasthenia gravis made
Test for antibodies - AchR, MuSK, LRP4
CT/MRI thymus
Edrophonium test - IV dose of edrophonium chloride (neostigmine) - block acetylcholinesterase enzyme in NMJ - relieves the weakness temporally
Describe the treatment of myasthenia gravis
Reversible anticholinesterase inhibitors - pyridostigmine and neostigmine
Immunosuppression - prednisolone and azathioprine
Thymectomy
Rituximab
Eculizumab
Describe a myasthenic crisis and its treatment
Severe complication of MG
Life threatening
Caused by other illness such as respiratory illness
Patients may require NIV or full intubation and ventilation
IVIG and plasma exchange may help
Which drug should be avoided in people with myasthenia
Beta blockers
Which anaesthetic drug are patients with myasthenia gravis often resistant to?
Suxamethonium
What is Lambert-Eaton Myasthenia
Slow progression
Proximal muscles more
Damage to the neuromuscular junction - antibodies produced by the immune system against voltage gated calcium channels in the presynaptic terminals of the NMJ
Tends to occur more in patients with small cell lung cancer
How is Lambert-eaton myasthenia treated?
Immunosuppressants - prednisolone or azathioprine
IV immunoglobulins
Plasmaphoresis
What is charcot marie tooth disease
Inherited disease that affects the peripheral motor and sensory nerves
Dysfunction in the myelin or the axons
Autosomal dominant pattern
Symptoms usually start to appear before the age of 10 but onset can be after 40
Name some classical features of Charcot Marie tooth disease
High foot arches
Distal muscle wasting causing inferted champagne bottle legs
Weakness in lower legs - ankle dorsiflexion
Weakness in the hands
Reduced tendon reflexes
Reduced muscle tone
Peripheral sensory loss
List the causes of peripheral neuropathy
Alcohol B12 deficiency Cancer and Chronic kidney disease Diabetes Drugs - isoniazid, amiodarone and cisplatin Vasculitides
Describe Guilian-Barre syndrome
Acute paralytic polyneuropathy - affects the PNS
Causes acute, symmetrical, ascending weakness and sensory symptoms
Which infections is Guillian Barre most associated with?
Campylobacter jejuni
Cytomegalovirus
Epstein Barr virus
Describe the pathophysiology of Guillian Barre syndrome
Molecular mimicry - B cells of the immune system create antibodies against antigens on the pathogen that causes the preceding infection
These antibodies also match the proteins on the nerve cells
They may have target proteins on the myelin sheath of the motor nerve cell or the nerve axon
Describe the presentation of Guillian Barre syndrome
Symmetrical ascending weakness
Reduced reflexes
Peripheral loss of sensation or neuropathic pain
Progress to affect the cranial nerves
Describe the clinical course of Guillian Barre syndrome
Symptoms start within 4 weeks of the preceding infection
Start in the feet and progress upwards
Symptoms peak within 2-4 weeks then a recover period can last moths to years
Describe how Guillian Barre is diagnosed
The Brighton criteria is used
Nerve conduction studies - reduced signal through nerves
LP for CSF - raised protein with a normal cell count and a normal glucose
How is Guillian Barre syndrome treated?
IV IG Plasma exchange Supportive care VTE prophylaxis Resp failure may require intubation, ventilation and admission
Describe the prognosis of Guillian Barre syndrome
80% fully recover
15% left with some neurological disability
5% will die
Describe neurofibromatosis
Nerve tumours throughout the nervous system
Benign - do cause neurological and structural problems
Two types - type 1 is more common than type 2
Describe neurofibromatosis type 1
NF1 gene mutations on chromosome 17 - neurofibromin (tumour suppressor gene). Inheritance is autosomal dominant
2 of the 7 features:
Cafe au lait spots
Relative with NF1
Axillary or inguinal freckles
Bony dysplasia - bowing of the long bone or sphenoid wing dysplasia
Iris haematomas - Lisch nodules (yellow brown spots on the iris)
Neurofibromas or plexiform neurofibroma
Glioma of the optic nerve
How do you investigate Neurofibromatosis
Genetic testing
X-ray - investigate bone pain and bone lesions #CT and MRI - investigate lesions in the brain, spinal cord and elsewhere in the body
Describe neurofibromatosis type 2
Chromosome 22 protein merlin (tumour suppressor protein) important in Schwann cells and mutations lead to development of schwannomas
What is neurofibromatosis most associated with?
Bilateral acoustic neuromas (hearing loss, balance problems, tinitus)
How is neurofibromatosis managed
Supportive - monitor the disease and treat any complications such as surgical resection
List some complications of neurofibromatosis type 1
Migraines
Epilepsy
Renal artery stenosis - causing hypertension
Learning and behavioural problems
Scoliosis of the spine
Vision loss
Malignant peripheral nerve sheath tumours
Gastrointestinal stromal tumour (sarcoma)
Brain tumours
Spinal cord tumour with associated neurology
Increased risk of breast cancer and leukaemia
List some red flags of headaches
Fever, photophobia, neck stiffness (meningitis, encephalitis)
New neurological symptoms (haemorrhage, malignancy, stroke)
Dizziness (stroke)
Visual disturbance (temporal arteritis or glaucoma)
Sudden onset occipital headache (SAH)
Worse on coughing or straining (raised ICP)
Postural, worse on standing, lying or bending over (raised ICP)
Severe enough to wake person up from sleep
Vomiting - raised ICP or CO poisoning
History of trauma (ICH)
Pregnancy (pre-eclampsia)
Describe a tension headache, the triggers and its management
Mild ache across the forehead in a band like pattern around the head
Due to muscle ache in frontalis, temporalis and occipitalis muscles
Come on and resolve gradually and do not produce any visual changes
Triggers - stress, depression, alcohol, skipping meals, dehydration
Treatment - reassurance, hot towels, relaxation techniques, basic analgesia
Describe what is meant by a secondary headache
Similar presentation to tension headache but with a clear cause
Non specific headache secondary to underlying medical conditions, alcohol, head injury and carbon monocide poisoning
Describe sinusitis and its course and treatment
Inflammation in the ethmoidal, maxillary, frontal or sphenoidal sinuses
Facial pain behind the nose, forehead, eyes
Tenderness over sinus
Resolves within 2-3 weeks
Most is viral
Nasal irrigation with saline can be helpful
Prolonged symptoms (>10 days) treated with steroid nasal spray and antibiotics are occasionally required
Describe what an analgesia overuse headache is and how it is treated
Long term analgesia use
Non specific features to a tension headache
Secondary to continous or excessive use of analgesia
Withdrawal of the analgesia is important in treating these headaches
Describe a hormonal headache
Related to low oestrogen
Non specific, generic, tension type headache
2 days before and first 3 days of period, around menopause and during pregnancy (2nd half pregnancy should raise suspicion of pre-eclampsia)
COCP can help treat this
Describe cervical spondylosis
Degenerative changes in the cervical spine
Causes neck pain made worse by movement
Presents with a headache
Exclude other causes of neck pain - inflammation, malignancy, infection
Describe trigeminal neuralgia
Trigeminal nerve has 3 branches - ophthalmic, maxillary, mandibular
Compression of the nerve
Occurs in patients with MS
Intense facial pain that comes on spontaneously and lasts for few seconds to hours
Often described as electrical shock pain
Attacks often worsen over time
Triggers - spicy food, cold weather, caffeine, citrus fruits
Carbamazepine or surgical decompression
List some types of migraine
Migraine without aura
Migraine with aura
Silent migraine
Hemiplegic migraine
Describe the headache in migraine
Lasts between 4 and 72hrs Moderate to severe in frequency Uusally unilateral but can be bilateral Photophobia and phonophobia With or without aura Nausea and vomiting
Describe the aura in migraine
Visual changes associated with migraine
- sparks in vision
- Blurring vision
- Lines across vision
- Loss of different visual fields
Describe a hemiplegic migraine
Mimics a stroke Typical migraine symptoms Sudden or gradual onset Hemiplegia - unilateral weakness of the limbs Ataxia Change in consciousness
List some triggers of migraines
Stress Bright lights Strong smells Certain food Dehydration Menstruation Abnormal sleep patterns Trauma
List the 5 stages of migraine
Prodromal stage (3 days before) Aura (60 mins) Headache (4 to 72hrs) Resolution stage - headache fades away or is relieved by vomiting or sleeping Postdromal/recovery
Describe the acute management of migraine
Paracetamol
Triptans - 5HT receptor agonists - smooth muscle contraction in arteries to cause vasoconstriction, peripheral pain receptors inhibited activation of pain, reduce neuronal activity in the CNS
NSAIDs
Antiemetics
Describe migraine prophylaxis
Propranolol Topiramate Amitriptyline Acupuncture Supplementation with B2 (riboflavin) Avoid triggers
What is a contraindication to topirmate
Pregnancy
Describe cluster headaches
Cluster of attacks and then disappear for a while
Typical patient is 30-50yo, smoker, triggered by alcohol, strong smell and exercise
Describe the symptoms of a cluster headache
Red, swollen and watering eye Pupil constriction (miosis) Eyelid drooping (ptosis) Nasal discharge Facial sweating
What is the treatment of cluster headache
Triptans - Sumatriptan 6mg SC
High flow O2 100% for 15-20mins
What prophylaxis of cluster headaches can be given
Verapamil
Lithium
Prednisolone - short course for 2-3 weeks to break the cycle
When is carotid endarterectomy performed
Symptomatic stenosis >75%
List some causes of myasthenic crisis
Pregnancy Emotion Exercise Chest sepsis Hypokalaemia Beta blockers Antibiotics -tetracyclines Opiates Acetylcholinesterase inhibitors
Problems with which structures can cause ptosis?
Midbrain
Cervical sympathetic chain
Oculomotor nerve
Describe pronator drift and what it signifies
Patient holds out arms with palms upwards
Observe for signs of pronation for 20-30 seconds
Ask patient to close eyes
Pronation with or without downward movement of the forearm suggests an UMN pyramidal tract lesion in the contralateral side as supinator’s are weaker than pronator muscles in this context
Describe spasticity
Associated with pyramidal tract lesions
Velocity dependent - the faster you move the limb, the worse it is - typically increased tone in intial part of movement which then suddenly reduces past a certain point - clasp knife spasticity - also accompanied by weakness
Describe rigidity
Velocity independent - feels the same no matter how fast you move the limb
What are the two types of rigidity
Cogwheel rigidity - involves a tremor superimposed on hypertonia resulting in intermittent increases in tone during movement of the limb - Parkinson’s disease
Lead pipe rigidity - uniformly increased tone throughout the movement of muscle - subtype of rigidity is typically associated with neuroleptic malignant syndrome
Describe the MRC power scale
0 - no contraction
1 - Flicker or trace of contraction
2- active movement, with gravity eliminated
3 - active movement against gravity
4 - active movement against gravity and resistance
5 - normal power
Which myotome and muscles are tested when assessing shoulder abduction
C5 (axillary nerve)
Deltoids
Which myotome and muscles are tested when assessing shoulder adduction
C6/7 (thoracodorsal nerve)
Latissimus dorsi, teres major, pectoralis major
Which myotome and muscles are tested when assessing elbow flexion
C5/6 (musculocutaneous and radial nerve)
Coracobrachialis, biceps brachii and brachialis
Which myotome and muscles are tested when assessing elbow extension
C7 (radial nerve)
Triceps brachii
Which myotome and muscles are tested when assessing the wrist extension
C6 (radial nerves)
Extensors of the wrist
Which myotome and muscles are tested when assessing wrist flexion
C6/7 (median nerve)
Flexors of the wrist
Which myotome and muscles are tested when assessing finger extension
C7 (radial nerve)
Extensor digitorium
Which myotome and muscles are tested when assessing finger abduction
T 1 (ulnar nerve) Abductor digiti minimi First dorsal interosseous
Which myotome and muscles are tested when assessing thumb abduction
T1 (median nerve)
Abductor pollicis brevis
Describe the pattern of weakness in an upper motor neuron lesion
Pyramidal weakness
Extensors in the upper limb are weaker than the flexors
Flexors in the lower limb are weaker than the extensors
Describe a reinforcement manoeuvre you can do to ensure the reflexes are absent
Ask patient to clench their teeth - relaxes the arms
Which myotome supplies the biceps reflex
C5/6
Where do you hit to elicit the biceps reflex
Medial aspect of the antecubital fossa
Which myotome is the supinator reflex
C5/6
Where do you hit to elicit the supinator (Brachioradialis) reflex
Brachioradialis tendon - 4 inches proximal to the base of the thumb on the posterolateral aspect of the wrist
Which myotome is the triceps reflex
C7
Where do you hit to elicit the triceps reflex
Triceps tendon - Superior to the olecranon process of the ulnar
Describe hyperreflexia
Associated with UMN lesion - loss of inhibition from higher brain centres which normally exert a degree of suppression over the lower motor neuron reflex arc
Describe hyporeflexia
LMN lesion - loss of efferent and afferent branches of the normal reflex arc
Describe the reflexes in cerebellar disease
Often normal
Can be pendular - less brisk and slower in their rise and fall
Describe where you would test each of the dermatomes
C5 - lateral aspect of the lower edge of the deltoid muscle
C6 - palmar side of the thumb
C7- palmar side of middle finger
C8 - palmar side of little finger
T1 - medial aspect of antecubital fossa,, proximal to medial epicondyle of Humerus
What does light touch sensation involve
Dorsal columns
Spinothalamic tract
What does pin-prick sensation involve
Spinothalamic tracts
What does vibration sense involve
Dorsal columns
What does proprioception involve
Dorsal columns
What causes peripheral neuropathy
Chronic alcohol excess
Diabetes mellitus
What is a radiculopathy
Nerve root damage
What is mononeuropathy
Nerve damage
What type of sensory disturbance is caused by a thalamic lesion
Contralateral sesnory loss
What type of weakness results from myopathy
Symmetrical proximal muscle weakness
Describe an intention tremor
Broad, coarse, low frequency tremor that develops as a limb reaches the endpoint of a deliberate movement
What does dysmetria and intention tremor suggest
Ipsilateral cerebellar pathology
What does dysdiadochokinesia suggest
Inability to perform rapid, alternating rapid movement - suggest ipsilateral cerebellar pathology
What is a broad based ataxic gait associated with?
Midline cerebellar pathology - lesion in MS or degeneration of the cerebellar vermis secondary to chronic alcohol excess
In unilateral cerebellar disease in which direction will patients veer to?
The side of the pathology
What does a high stepping gait possibly indicate
Foot drop
What does tandem gait show
Dysfunction of cerebellar vermis (alcohol induced cerebellar degeneration)
Weak flexors or sensory ataxia
Describe hemiparetic gait
One leg held stiffly and swings round in an arc with each stride (circumduction) - associated with stroke
Describe spastic paraparesis gait
Bilateral hemiparetic gait with both legs stiff and circumduction
Inverted and scissor feet
Hereditary spastic paraplegia
Describe Romberg’s test
Ask patient to put feet together and arms by their side
Close eyes - if patient has proprioceptive or vestibular dysfunction then will struggle to remain standing
What is a positive Romberg’s and what does it suggest
Falling without correction
Sensory ataxia - proprioceptive dysfunction (Ehlers Danlos), B12 deficiency, Parkinson’s disease and ageing
Vestibular dysfunction - vestibular neuronitis and Menieres disease
What does swaying with correction during rombergs test suggest
Rombergs negative
Cerebellar disease due to truncal ataxia
Describe what may be observed with increased tone in the leg
When lifting knee off the bed, the ankle will come up too
Describe ankle clonus
Involuntary rhythmic muscular contractions and relaxations that is associated with UMN lesions of the descending motor pathways (stroke, MS, cerebral palsy)
Position patients legs so the knee and ankle are slightly flexed, supporting the leg with your hand under their knee so they can relax
Rapidly dorsiflex and partially evert the foot to stretch gastrocnemius muscle
Keep the foot in this position and observe for clonus (>5 rhythmic beats of dorsiflexion and plantarflexion)
Which myotomes and muscles are assessed when testing hip flexion
L1/2 (iliofemoral nerve)
Iliopsoas
Which myotomes and muscles are assessed when testing hip extension
L5/S1/S2
Gluteus maximus
Which myotomes and muscles are assessed when testing knee flexion
S1 (Sciatic nerve)
Hamstrings
Which myotomes and muscles are assessed when testing knee extension
L3/4 (femoral nerve
Quadriceps
Which myotomes and muscles are assessed when testing ankle dorsiflexion
L4/5 (deep peroneal nerve)
Tibialis anterior
Which myotomes and muscles are assessed when testing ankle plantarflexion
S1/2
Tibial nerve
Gastrocnemius and soleus
Which myotome and muscles are assessed when testing big toe extension
L5 (deep peroneal nerve)
Extensor hallucis longus
Which myotome is associated with the patella reflex
L3/4
Which myotome is associated with the ankle jerk reflex
S1
Which myotome is associated with the plantar reflex
L5 and S1
Describe babinskis sign
Extension of the big toe and spreading of the other toes - UMN lesion
What is L1 dermatome
Inguinal region and very top of medial thigh
What is the L2 dermatome
Middle and lateral aspect of anterior thigh
What is the L3 dermatome
MEDIAL ASPECT OF KNEE
What is the L4 dermatome
Medial aspect of lower leg and ankle
What is the L5 dermatome
Dorsum and medial aspect of big toe
What is the S1 dermatome
Dorsum and lateral aspect of the little toe
What does inability to perform heel to shin test show
Incoordination - Dysmetria - ipsilateral cerebellar pathology
What is a relative afferent pupillary defect and what does it show
Constriction less so in the affected pupil
Swinging light test shows relative pupillary dilation when light shone from healthy eye to damaged eye
Retinal damage - central retinal artery occlusion, vitreous
detachment , compression due to tumour or abscess
Optic neuritis
What is an unilateral efferent defect and what does it show
Compression caused by the extrinsic pathway
Ipsilateral pupil dilates and is non-responsive but consensual response the unaffected pupil is normal
What is visual neglect and what does it show?
Deficiet in awareness of one side of the visual field
Stroke in contralateral parietal region
What is the function of the inferior oblique
Elevates, abducts and laterally rotates the eyeball
What is the function of the superior oblique
Depresses, abducts and medially rotates the eyeballs
Describe the function of the medial rectus
Adducts the eyeball
Describe the function of the lateral rectus
Abduct the eyeball
Describe the function of the superior rectus
Elevation, adduction, medial rotation of the eyeball
Describe the function of the inferior rectus
Depression, adduction and lateral rotation of the eyeball
What are the features of an oculomotor nerve palsy
Down and out pupil
Ptosis
Mydriasis
What are the features of a trochlear nerve palsy
Vertical diplopia when looking inferiorly
Which muscle is supplied by the trochlea nerve
Superior oblique
Which muscle is supplied by the abducens nerve
Lateral rectus muscle
What does abducens nerve palsy cause
Convergent squint
Horizontal diplopia
What is a normal rinnes test
Air conduction > Bone conduction
What would be the Rinnes test for sensorineural deafness
Air conduction >Bone conduction
Rinnes positive
What would be the Rinnes test for conductive deafness
Bone conduction > Air conduction
Rinnes negative
Describe normal Weber’s
Sound heard equally in both ears
Describe Weber’s in sensorineural deafness
Sound head louder in the normal ear
Describe Weber’s in conductive deafness
Sound heard louder on the side of the affected ear
Describe the head thrust test/vestibular ocular reflex
Ask pt if they have any neck problems
Tell pt to focus on your nose at all times
Turn their head rapidly to left and then to right
Normal - eyes fix on your nose
Vesibular pathology - eyes move in direction of head movement before a corrective refixation saccade towards your nose
