Week 12 - Neurology Flashcards
What is the most common cause of radial nerve palsy? How does it present?
Entrapment at spiral groove - i.e. Saturday night palsy or sleeping with someone resting on your arm.
Wrist and finger drop, usually painless, sensory change over back of thumb index and middle finger.
What is the most common cause of ulnar nerve palsy? How does it present?
Entrapment at ulnar groove (medial epicondyle of humerus.)
May be history of trauma at the elbow, sensory disturbance over front and back of pinkie and ring finger, weak grip, usually painless.
What is the most common cause of median nerve palsy? What are the presenting symptoms?
Entrapment within carpal tunnel at wrist.
Presenting symptoms: history of intermittent nocturnal pain, numbness and tingling often relieved by shaking the hand. Patient may complain of weak grip, positive tinel’s sign (parasthesia in the distribution of the nerve when it is gently percussed.
What is the most common cause of palsy of the Anterior Interosseous branch of the median nerve?
Trauma to forearm.
History of forearm pain, patient may complain of weak grip of keys, positive tinel’s sign, no sensory change.
What is the most common cause of femoral nerve palsy? What are the presenting symptoms?
Cause: haemorrhage, trauma.
Presenting symptoms: weakness of quadriceps, weakness of hip flexion, numbness in medial shin (from thigh down to leg).
What is the most common cause of palsy of the common peroneal nerve? What are the presenting symptoms?
Entrapment at fibular head.
History of trauma, surgery or external compression.
Acute onset of foot drop or sensory disturbance (lateral top of leg), usually painless.
What is mononeuritis multiplex? What are the common causes?
Simultaneous or sequential development of palsy of 2 or more nerves.
Diabetes, vasculitic causes, rheumatological (i.e. RA), infective (i.e. Hep C, HIV), sarcoidosis, lymphoma.
What are the protective connective tissue layers surrounding peripheral nerves in fascicles?
Endoneurium
Perineurium
Epineurium
What is the function of large myelinated fibres in the PNS?
Motor nerves
Proprioception, vibration, light touch,
How does neuropathy present in:
- Motor fibres
- Sensory fibres
- Autonomic fibres
Motor - muscle weakness and atrophy
Sensory:
Large (myelinated fibres) sensory ataxia, loss of vibratory sense +/- tingling. Small (thinly myelinated/myelinated) fibres - impaired pin prick, temperature, painful burning, numbness and tingling.
Autonomic - postural hypotension, erectile dysfunction, GI disturbance, abnormal sweating.
Describe the features of length dependant axonal neuropathy.
Diffuse involvement of peripheral nerves. Length dependant - starts in toes/feet. Symmetrical. Slowly progressive. No significant sensory ataxia. Any weakness is distal and mild.
What are the causes of length-dependent axonal
neuropathy?
Diabetes, alcohol, nutritional (folate, B12, thiamine, B6 deficiency), immune related (RA, lupus), renal failure, hypothyroidism, drugs (isoniazid, amiodarone), infectious (HIV, hepatitis B and C), inherited, myeloma.
Describe the features of guillain-barre syndrome. How is it treated?
Progressive, ascending (starts in hands and feet) weakness, numbness and pain over days.
Flaccid quadraparesis with areflexia.
+/- respiratory/bulbar/autonomic involvement.
Post infectious autoimmune aetiology (e.g. campylobacter, EBV)
Treated with IVIG or apheresis.
Chronic form (steroid and IVIG responsive)
What are the clinical features of muscle disease in the following systems:
- Limbs
- Face
- Eyes
- Bulbar
- Neck and spine
- Respiratory
- Myocardial
Proximal limb weakness - difficulty raising arms above head, arising from seat.
Facial weakness - characterisic myopathic facies, drooling.
Eyes - ptosis, opthalamoplegia.
Bulbar - dysarthria (speech difficulty), dysphagia.
Neck and spine - head drop, scoliosis.
Respiratory - breathlessness (especially when lying flat).
Myocardial - exercise intolerance, palpitations.
What are some of the causes of muscle disease?
Muscular dystrophies i.e. duchenne, becker.
Inflammatory muscle disease i.e. polymyositis, dermatomyositis.
Neuromuscular junction disorders - myasthenia gravis.
Metabolic muscle disorders - glycogen storage diseases.
What is Myasthenia Gravis and its pathogenesis?
Autoimmune disorder: antibodies to acetylcholine receptor at post synaptic NMJ.
Fatiguable weakness of ocular, bulbar, neck, respiratory and/or limb muscles.
How is it investigated and managed?
Investigation - antibodies to AChr present in 85% of cases.
Single fibre EMG (electromyography) and repetitive nerve stimulation also abnormal.
Managed with pyridostigmine (anti-acetylcholine esterase) and immunosuppressive therapies (e.g. steroids and IVIG)
Define primary and secondary headache and give a few examples of each.
Primary headache - the headache and it’s associated features is the disorder (no underlying cause) i.e. migraine, tension-type headache, cluster headache.
Secondary headache - the headache is secondary to an underlying cause i.e. subarachnoid haemorrhage,, space occupying lesion, meningitis, temporal arteritis, high/low intracranial pressure, drug induced.
What are some of the red flag features of secondary headache?
Age >50 years, thunderclap headache, focal/non-focal neurological deficit, worsening of symptoms with posture, valsava or physical exertion.
Early morning headaches.
Systemic symptoms - fever, weight loss.
Seizures, meningism.
Temporal artery tenderness, jaw claudication.
Specific situations - cancer, pregnancy, post partum, HIV/immunosuppression.
Abnormal signs in a clinical examination of a patient with a headache suggests a secondary cause of the headache. What abnormal signs may be present?
General/systemic - reduced conscious level, reduced BP, pyrexia, menignism, skin rash, temporal artery tenderness.
Cranial nerve - pupillary responses, visual fields +/- blind spot, eye movements, fundoscopy.
What is the clinical features of a migraine headache?
Prodrome - reported 40-60%, up to 48 hours before headache, variable symptoms - mood disturbance, photophobia, hyperosmia, restlessness, diarrhoea.
Aura - develops 5-20 minutes and lasts <60 mins. Visual aura most common, sensory aura often starts in hand and migrates up arm.
Headache - throbbing/pulsatile, moderate-severe intensity, duration 4-72 hours, unilateral in 60% of cases, aggravated by routine physical activity.
Associated symptoms - nausea and vomiting, photophobia, phonophobia, osmophobia, mood disturbance, diarrhoea, autonomic disturbance: lacrimation, conjunctival injection, nasal stuffiness.
What is the investigation and management of migraine?
Good history and normal clinical examination does not require further investigation. Cranial imaging if red flags or aura >24 hours.
Avoid triggers, reduce alcohol and caffeine, regular meals and sleep patterns. Simple analgesia (i.e. paracetamol, aspirin, NSAIDs.) Triptans, antiemetics (i.e. metoclopramide). Prophylaxis: beta blockers, tricyclic antidepressants (i.e. amitriptyline), anti-epilepsy drugs (topiramate).
What is a medication overuse headache (MOH)?
Headache of 15+ days per month associated with frequent use of acute relief medications (e.g. NSAIDs).
What is a thunderclap headache? What should it be treated as until proven otherwise?
Abrupt-onset of severe headache which reaches maximal intensity <5mins (and lasts >1hr). Subarachnoid haemorrhage.
What are the causes of thunderclap?
Subarachnoid haemorrhage
Intracerebral haemorrhage;
Arterial dissection (vertebral or carotid);
Cerebral venous sinus thrombosis;
Bacterial meningitis;
Rare – spontaneous intracranial hypotension,
pituitary apoplexy;
Primary headaches (eg. migraine, exertional
headache, cluster headache) – diagnosis of
exclusion
How is a thunderclap headache investigated?
Bloods - U&E. LFT, glucose, FBC, coagulation screen, CRP. Blood cultures if pyrexial.
12 lead ECG
Urgent CT brain
Lumbar puncture - after 12 hours to look for xanthochromia.
What is a normal intra cranial pressure?
7-15 mmHg
Why is raised intracranial pressure a problem?
Because global brain perfusion is reduced when ICP is raised and therefore cerebral metabolism is reduced.
What features of the history would indicate a raised pressure headache?
Worse when lying flat, worse in the morning, persistent nausea and vomiting, worse of valsalva (coughing, laughing, straining), worse with physical exertion, transient visual obscuration with change in posture.
What examination findings would indicate a raised pressure headache?
Optic disc swelling (papilloedema), impaired visual acuity/colour vision, restricted visual field/enlarged blind spot, 3rd nerve palsy, 6th nerve palsy, focal neurological signs.
What can cause raised ICP?
Mass effect - i.e. tumour infarction with oedema, subdural, extradural, intracerebral haematoma, abscess.
Increased venous pressure - cerebral venous sinus thrombosis, obstruction of jugular venous system.
Obstruction to CSF flow/absorption - hydrocephalus, meningitis.
Idiopathic - idiopathic intracranial hypertension.
What are the features of low CSF pressure headaches?
Headache worse standing/sitting, better lying down.
What are the causes of low CSF pressure headaches?
Post-lumbar puncture, should resolve spontaneously.
Spontaneous intracranial hypotension - results from spontaneous dural tear, sometimes following valsalva.
Define stroke.
Central nervous system infarction based on evidence of focal ischaemic injury in a defined vascular distribution.
Define ischaemic stroke.
An episode of neurological dysfunction caused by focal cerebral, spinal or retinal infarction.
What proportion of strokes are haemorrhagic and ischaemic?
15-20% haemorrhagic
80-85% ischaemic
Define stroke caused by intracerebral haemorrhage.
Rapidly developing clinical signs of neurological dysfunction due to focal collection of blood within the brain parenchyma or ventricular system that is not caused by trauma.
What are the clinical features of stroke?
Weakness: leg/face/arm/hemiparesis
Dysphasia
Visual disturbance: right homonymous hemianopia
Acute light-headedness (past pointing, nystagmus).
What is the acute management of a stroke?
Admission to stroke unit - all patients!
Brain imaging
IV thrombolysis (within 4.5 hours of symptom onset)
Thrombectomy (within 6-8 hours of symptom onset.)
Effective secondary prevention.
Outline the different parts of the Glasgow Coma Scale and how you would assess it?
Eye opening 4 - spontaneous 3 - to sound 2 - to pain 1 - none
Verbal response 5 - orientated 4 - confused 3 - words 2 - incomprehensible sounds 1 - none
Motor response 6 - obeys commands 5 - localizes pain 4 - normal flexion 3 - abnormal flexion 2 - extension 1 - none
What is internuclear opthalmoplegia? A lesion of what area causes this? What condition is it commonly seen in?
Disorder of conjugate gaze - failure of adduction of the affected eye with nystagmus on lateral gaze in contralateral eye.
Medial longitudinal fasiculus.
Multiple sclerosis.
What would the difference be between an upper motor neuron facial weakness and a low motor neuron facial weakness?
Upper motor neuron - weakness of inferior facial muscles only
Lower motor neuron - weakness of the superior and inferior facial muscles.
What kind of aphasia would damage to wernicke’s and broca’s area produce?
Wernickes - receptive aphasia, difficulty comprehending speech and can speak but doesn’t make sense.
Broca’s - expressive aphasia, can understand speech but can’t express themselves and form sentences.
What is dementia?
Progressive cognitive decline involving a minimum of 2 of the the following domains:
- memory
- executive function
- language
- apraxia/visuospatial
Define seizure.
Define Epilepsy.
- Episode of neuronal hyperactivity.
- At least two unprovoked episodes of seizure.
What are the two broad types of epilepsy?
Focal or generalised
What should you do if you see someone having a seizure?
Put them in the recovery position.
If movements stop and no impairment to ABGs, does not need hospitalisation if recovers awareness.
What are the features of focal epilepsy?
History trauma/birth injury Focal aura/sequelae (including gustatory/sensory/motor features) Post attack confusion/drowsiness Automatisms Nocturnal events
What are the features of genetic generalised epilepsy?
Photosensitivity Age of onset 8-26 Alcohol or sleep deprivation Myoclonus (especially in am) Lack of aura Seizures within 2 hours of awakening Family history of IGE EEG abnormal
What investigation is needed for seizure?
Brain imaging - CT or MRI (MRI for children!)
EEG
Systemic provocation
Define status epilepticus.
> 2 seizures without full recovery of neurologic function between seizures or continuous seizure activity > 30 minutes
What is the medical therapy for focal epilepsy?
Lamotrigine, carbamazepine, levetiracetam
What is the medical therapy for generalised epilepsy?
valproate, levetiracetem, lamotrigine
What are the functions of the basal ganglia? What neurotransmitter does the basal ganglia use?
Decision to move
Direction of movement
Motor memory
Maintaining posture
Dopamine
Describe the pathology of Parkinson’s disease.
Loss of dopaminergic neurons within the substantia nigra. Surviving neurons contain Lewy bodies.
What 2 misfolded proteins are found within Lewy bodies?
α-synuclein and Ubiquitin
What are the clinical features of parkinsonism?
Bradykinesia + two of the following:
- muscular rigidity
- 4-6 Hz rest tremor
- Postural instability
What are some of the non-motor symptoms of Parkinson’s disease?
Neuropsychiatric - dementia, depression, anxiety.
Sleep - REM sleep behaviour disorder, restless leg syndrome, daytime somnolence.
Autonomic - constipation, urinary urgency/nocturia, ED, excessive salivation/sweating, postural hypotension.
Other - reduced sense of smell, fatigue, pain and sensory symptoms.
What investigations would you undertake for parkinson’s disease?
Bloods - if tremor present: thyroid function tests, copper/caeruloplasmin.
Structural imaging - CT/MRI brain normal in PD, abnormal in vascular parkinsonism, parkinson plus disorders.
Functional imaging - imaging of presynaptic dopaminergic function using DAT SPECT is abnormal in degenerative parkinsonism.
What drug classes can be used in treatment of PD?
L-dopa
Dopamine agonists
MOA-B inhibitors
COMT - inhibitors
What are the complications in advanced PD?
Motor On/off fluctuations (medication wears off) L-dopa induced dyskinesia Poor balance/falls Speech/swallowing disturbance
Cognitive
Dementia
What is the surgical option for parkinson’s disease?
Deep brain stimulation of subthalamic nucleus.
What member of the multidisciplinary team are involved in the care of the patient with PD?
GP Neurologist/care of the elderly specialist Parkinson's disease nurse specialist Physiotherapist Speech and language therapy Psychiatrist Psychologist OT Palliative care team Neurosurgeon
What are some of the degenerative and secondary causes of parkinsonism?
Degenerative - dementia with lewy bodies
Progressive supranuclear palsy
Multiple system atrophy
Corticobasal degeneration
Secondary Drug induced - chronic use of dopamine agonists Cerebrovascualr disease Toxins i.e. CO Post-infectious
What is MS?
An idiopathic inflammatory demylinating disease of the CNS.
What are the 4 subtypes of MS?
Relapsing remitting MS
Primary progressive MS
Secondary progressive MS
Benign MS
Name 4 syndromes that may develop into MS?
Optic neuritis
Clinically isolated syndromes
Transverse myelitis
Radiologically isolated syndromes.
What is the diagnostic criteria for multiple sclerosis?
Evidence of 2 or more episodes of demylination disseminated in space and time.
What causes MS?
Genetic factors
Lack of sunlight/vitamin D
Viral trigger - i.e. EBV
Smoking
When should you suspect MS?
Neurological symptoms that develop over a few days, a history of transient neurological symptoms that last more than 24 hours and spontaneously resolve.
Optic neuritis
Bell’s palsy
Labyrinthitis
Sensory symptoms
Bladder symptoms in young man/woman without children
What do you investigate suspected MS?
MRI brain and cervical spine with gadolinium contrast.
Additional - lumbar puncture, bloods to exclude other conditions, visual evoked potentials, CXR - to exclude sarcoidosis.
How MS treated?
Steroids i.e. oral or IV methylprednisolone + PPI to treat relapses.
Disease modifying treatments - i.e. alemtuzimab and beta interferon
What is treatment for primary progressive MS?
- No disease modifying treatments
- most treatment aimed at rehabilitation and control of symptoms.
What would be the treatment for subarachnoid haemorrhage?
Initial - fluid resuscitation, analgesia, prevent/treat vasospasm with nimodipine
Endovascular coiling/neurosurgical clipping
May require anti-epileptic drugs to deal with seizures. May require extraventricular drain to prevent hydrocephalus.
