Neuro 3 Flashcards
What is Hoffman’s sign?
Like the babinski reflex but of the upper limb.
Flick middle nail and watch how thumb moves.
Which antiemetic can precipitate extrapyramidal side-effects?
Metoclopramide
What is Lhermitte’s sign?
Symptoms worse when flexing neck
Give examples of dopamine receptor agonists
Bromocriptine
Cabergoline
Apomorphine
Ropinirole
Give examples of COMT inhibitors
Entacapone
Tolcapone
What can be used to treat drug induced parkinsons?
Antimuscarinics
- help reduce tremor and rigidity
- procyclidine, benzotropine, trihexyphenidyl
What is more common if patients have had haemorrhagic stroke?
- decreased consciousness
- headache
- nausea and vomiting
- seizures
What are the causes of Parkinsonism?
- Parkinson’s disease
- drug-induced e.g. antipsychotics, metoclopramide - see below
- progressive supranuclear palsy
- multiple system atrophy
- Wilson’s disease
- post-encephalitis
- dementia pugilistica (secondary to chronic head trauma e.g. boxing)
- toxins: carbon monoxide, MPTP
Drugs causing Parkinsonism
phenothiazines: e.g. chlorpromazine, prochlorperazine
butyrophenones: haloperidol, droperidol
metoclopramide
How would you manage a stroke?
- blood glucose, hydration, oxygen saturation and temperature should be maintained within normal limits
- blood pressure should not be lowered in the acute phase unless there are complications e.g. Hypertensive encephalopathy*
- aspirin 300mg orally or rectally should be given as soon as possible if a haemorrhagic stroke has been excluded
- with regards to atrial fibrillation, the RCP state: ‘anticoagulants should not be started until brain imaging has excluded haemorrhage, and usually not until 14 days have passed from the onset of an ischaemic stroke’
- if the cholesterol is > 3.5 mmol/l patients should be commenced on a statin. Many physicians will delay treatment until after at least 48 hours due to the risk of haemorrhagic transformation
When would you thrombolyse someone?
- it is administered within 4.5 hours of onset of stroke symptoms (unless as part of a clinical trial)
- haemorrhage has been definitively excluded (i.e. Imaging has been performed)
What do NICE recommend for thrombolysis?
Alteplase
What are the contraindications to thrombolysis?
Absolute
- Previous intracranial haemorrhage
- Seizure at onset of stroke
- Intracranial neoplasm
- Suspected subarachnoid haemorrhage
- Stroke or traumatic brain injury in preceding 3 months
- Lumbar puncture in preceding 7 days
- Gastrointestinal haemorrhage in preceding 3 weeks
- Active bleeding
- Pregnancy
- Oesophageal varices
- Uncontrolled hypertension >200/120mmHg
Relative
- Concurrent anticoagulation (INR >1.7)
- Haemorrhagic diathesis
- Active diabetic haemorrhagic retinopathy
- Suspected intracardiac thrombus
- Major surgery / trauma in preceding 2 weeks
What would you do as secondary prevention of stroke?
- clopidogrel is now recommended by NICE ahead of combination use of aspirin plus modified release (MR) dipyridamole in people who have had an ischaemic stroke
- aspirin plus MR dipyridamole is now recommended after an ischaemic stroke only if clopidogrel is contraindicated or not tolerated, but treatment is no longer limited to 2 years’ duration
- MR dipyridamole alone is recommended after an ischaemic stroke only if aspirin or clopidogrel are contraindicated or not tolerated, again with no limit on duration of treatment
With regards to carotid artery endarterectomy:
- recommend if patient has suffered stroke or TIA in the carotid territory and are not severely disabled
- should only be considered if carotid stenosis > 70% according ECST** criteria or > 50% according to NASCET*** criteria
What are the features of Arnold Chiari malformation?
- non-communicating hydrocephalus may develop as a result of obstruction of cerebrospinal fluid (CSF) outflow
- headache
- syringomyelia
What are the types and features of chiari malformation?
I Herniation of cerebellar tonsils
- sometimes with syringomyelia
II (Arnold Chiari) Herniation of cerebellar vermis
- usually accompanied by a lumbar myelomeningocele
III Occipital encephalocele
- usually with syringomyelia, a tethered cord and hydrocephalus
IV lack of cerebellar development
- not compatible with life
What are the features of parkinsons disease?
- tremor (3-5Hz)
- rigidity
- bradykinesia
- mask-like facies
- flexed posture
- micrographia
- drooling of saliva
- psychiatric features: depression is the most common feature (affects about 40%); dementia, psychosis and sleep disturbances may also occur
- impaired olfaction
- REM sleep behaviour disorder
- fatigue
- postural hypotension
Stopping levodopa can cause what serious condition?
neuroleptic malignant syndrome
The long arm of which chromosome is typically deleted in NF2?
22
The long arm of which chromosome is typically deleted in NF1?
17
What wave activity is seen in someone who is awake but has their eyes closed?
alpha wave 8-13 Hz
What would alexia without agraphia indicate?
A lesion involving the left occipital lobe and splenium of the corpus callosum
What kind of drug is alteplase?
recombinant tissue plasminogen activator (rtPA)
What pattern of EEG would you expect for a childhood abscent seizure?
3 Hz spike-and-wave
What test would you do if you expected an inflammatory myopathy?
CPK (serum creatinine phosphokinase
What is pleocytosis?
the presence of an abnormally large number of lymphocytes in the cerebrospinal fluid. GBS associated with HIV. Normal GBS doesn’t have high cell count
How would CSF from a patient with GBS appear?
- Lots of protein
- Yellowish
- Viscous
What would the following make you think of?
Progressive behavioral disturbances, hallucinations, seizures and obtundation (less than full alertness)
Herpes simplex type 1 encephalitis
What is dysaesthesia?
an abnormal unpleasant sensation felt when touched, caused by damage to peripheral nerves.
What is the thalamic pain syndrome?
Decrease pain sensitivity in an area but paradoxical pain.
What’s the most common cause of lobar haemorrhage in elderly patients without hypertension?
Cerebral amyloid angiopathy
Deposition of beta-amyloid protein in blood vessels of the brain leads to disruption of the vessel walls, which predisposes them to haemorrhage. Old haemorrhages may be seen on gradient echo MRI which magnifies the effects of haemosiderin.
What is a mycotic aneurysm?
A mycotic aneurysm is a dilation of an artery due to damage of the vessel wall by an infection. It is also referred to as infected aneurysm.
What’s likely to bleed during exertion such as sex and defecation?
Mycotic aneurysm
What’s the term for a cholesterol emboli that blocks the central retinal artery?
Hollenhorst plaque
What’s heel-to-toe walking known as?
A tandem gait
How does carbamazapine work?
binds to sodium channels increases their refractory period (similar to TCA drugs)
What is carbamazapine used for?
- treatment of epilepsy, particularly partial seizures, where carbamazepine remains a first-line medication.
- neuropathic pain (e.g. trigeminal neuralgia, diabetic neuropathy)
- bipolar disorder
What are the side effects of carbamazapine?
- P450 enzyme inducer
- dizziness and ataxia
- drowsiness
- headache
- visual disturbances (especially diplopia)
- Steven-Johnson syndrome
- leucopenia and agranulocytosis
- hyponatraemia secondary to syndrome of inappropriate ADH secretion
What are the risk factors for Degenerative cervical myelopathy (DCM)?
- smoking due to its effects on the intervertebral discs
- genetics
- occupation - those exposing patients to high axial loading
What reflex would you test for DCM?
Hoffman’s sign: is a reflex test to assess for cervical myelopathy. It is performed by gently flicking one finger on a patient’s hand. A positive test results in reflex twitching of the other fingers on the same hand in response to the flick.
What’s the average age of onset of a bells palsy?
20-40 years
What are the signs and symptoms of Bell’s palsy?
- lower motor neuron facial nerve palsy - forehead affected
- patients may also notice post-auricular pain (may precede paralysis)
- altered taste
- dry eyes
- hyperacusis
How would you manage someone with Bell’s palsy?
- in the past a variety of treatment options have been proposed including no treatment, prednisolone only and a combination of aciclovir and prednisolone
- following a National Institute for Health randomised controlled trial it is now recommended that prednisolone 1mg/kg for 10 days should be prescribed for patients within 72 hours of onset of Bell’s palsy. Adding in aciclovir gives no additional benefit
- eye care is important - prescription of artificial tears and eye lubricants should be considered
Prognosis
-if untreated around 15% of patients have permanent moderate to severe weakness
What are the side effects of phenytoin?
Acute
- initially: dizziness, diplopia, nystagmus, slurred speech, ataxia
- later: confusion, seizures
Chronic
- common: gingival hyperplasia (secondary to increased expression of platelet derived growth factor, PDGF), hirsutism, coarsening of facial features, drowsiness
- megaloblastic anaemia (secondary to altered folate metabolism)
- peripheral neuropathy
- enhanced vitamin D metabolism causing osteomalacia
- lymphadenopathy
- dyskinesia
Idiosyncratic
- fever
- rashes, including severe reactions such as toxic epidermal necrolysis
- hepatitis
- Dupuytren’s contracture
- aplastic anaemia
- drug-induced lupus
How do you treat tension type headaches?
- acute treatment: aspirin, paracetamol or an NSAID are first-line
- prophylaxis: NICE recommend ‘up to 10 sessions of acupuncture over 5-8 weeks’
- low-dose amitriptyline is widely used in the UK for prophylaxis against tension-type headache. The 2012 NICE guidelines do not however support this approach ‘…there was not enough evidence to recommend pharmacological prophylactic treatment for tension type headaches. The GDG considered that pure tension type headache requiring prophylaxis is rare. Assessment is likely to uncover coexisting migraine symptomatology with a possible diagnosis of chronic migraine.’
What are the causes of raised ICP?
- trauma
- SOL (tumours, intracranial haemorrhage, abcess)
- hydrocephalus
- spontaneous haemorrhage
- infection
- venous sinus thrombosis
- IIH
Differentials for a sudden onset headache
- SAH
- intracerebral haemorrhage
- ischaemic stroke
- venous sinus thrombosis
- carotid/vertebral artery dissection
- hypertensive encephalopathy
- meningitis
- pituitary apoplexy
What’s used to treat nausea?
ondansetron
granisetron
(5HT3 antagonists)
What is an essential tremor exacerbated and alleviated by?
Essential tremor is an AD condition that is made worse when arms are outstretched, made better by alcohol, rest and propranolol
What’s the criteria for migraine?
A At least 5 attacks fulfilling criteria B-D
B Headache attacks lasting 4-72 hours* (untreated or unsuccessfully treated)
C Headache has at least two of the following characteristics:
- unilateral location*
- pulsating quality (i.e., varying with the heartbeat)
- moderate or severe pain intensity
- aggravation by or causing avoidance of routine physical activity (e.g., walking or climbing stairs)
D During headache at least one of the following:
- nausea and/or vomiting*
- photophobia and phonophobia
E Not attributed to another disorder
What can cause an ataxic gait?
P - Posterior fossa tumour A - Alcohol S - Multiple sclerosis T - Trauma R - Rare causes I - Inherited (e.g. Friedreich's ataxia) E - Epilepsy treatments S - Stroke
Which anaesthetic drugs are MG patients more resistant to?
Suxamethonium is a depolarising NMBD (neuromuscular blocking drug) - it acts by binding to and activating the receptor, at first causing muscle contraction, then paralysis. Again, due to a decreased number of available receptors, MG patients are typically resistant to depolarising NMBDs and may require significantly higher doses.
Which medications are associated with IIH?
- tetracycline antibiotics
- isotretinoin
- contraceptives
- steroids
- levothyroxine
- lithium
- cimetidine
What sort of field loss would you expect with primary open angle glaucoma?
Unilateral peripheral visual field loss
What are the causes of spontaneous SAH?
- Intracranial aneurysm* (saccular ‘berry’ aneurysms): this accounts for around 85% of cases. Conditions associated with berry aneurysms include adult polycystic kidney disease, Ehlers-Danlos syndrome and coarctation of the aorta
- Arteriovenous malformation
- Pituitary apoplexy
- Arterial dissection
- Mycotic (infective) aneurysms
- Perimesencephalic (an idiopathic venous bleed)
Can you use a cervical x-ray to diagnose degenerative cervical myelopathy?
No, you can’t visualise the soft tissue
What are the side effects of levodopa?
- dyskinesia
- ‘on-off’ effect
- postural hypotension
- cardiac arrhythmias
- nausea & vomiting
- psychosis
- reddish discolouration of urine upon standing
How would you treat a migraine during pregnancy?
- paracetamol 1g is first-line
- aspirin 300mg or ibuprofen 400mg can be used second-line in the first and second trimester
How would you treat menstrual migraines?
- mefanamic acid or a combination of aspirin, paracetamol and caffeine. Triptans are also recommended in the acute situation
How would you investigate an acoustic neuroma?
MRI of cerebellopontine angle
Which drug can be used as an antiemetic in parkinsons disease?
Domperidone
What bedside test would you do to see if fluid is CSF?
Glucose. Beta-2-transferrin would be the gold standard but takes longer.
Glucose: 50-80mg/dl
Protein: 15-40 mg/dl
Red blood cells: Nil
White blood cells: 0-3 cells/ mm3
What are the red flags for headache?
- compromised immunity, caused, for example, by HIV or immunosuppressive drugs
- age under 20 years and a history of malignancy
- a history of malignancy known to metastasis to the brain
- vomiting without other obvious cause
- worsening headache with fever
- sudden-onset headache reaching maximum intensity within 5 minutes
- new-onset neurological deficit
- new-onset cognitive dysfunction
- change in personality
- impaired level of consciousness
- recent (typically within the past 3 months) head trauma
- headache triggered by cough, valsalva (trying to breathe out with nose and mouth blocked), sneeze or exercise
- orthostatic headache (headache that changes with posture)
- symptoms suggestive of giant cell arteritis or acute narrow-angle glaucoma
- a substantial change in the characteristics of their headache
How would you treat a generalised tonic-clonic seizure?
sodium valproate (not for females) second line: lamotrigine, carbamazepine
How would you treat an abscence seizure?
- sodium valproate or ethosuximide
- sodium valproate particularly effective if co-existent tonic-clonic seizures in primary generalised epilepsy
!! carbamazepine may exacerbate absence seizures
How would you treat myoclonic seizure?
sodium valproate
second line: clonazepam, lamotrigine
!! carbamazepine may exacerbate myoclonic seizures
How would you treat focal seizure?
carbamazepine or lamotrigine
second line: levetiracetam, oxcarbazepine or sodium valproate
What are the signs of autonomic dysreflexia?
- severe hypertension
- flushing
- sweating without a congruent response in heart rate
Autonomic dysreflexia can only occur if the spinal cord injury occurs above what level?
T6
What’s the difference between GBS and CIDP?
CIDP is like GBS but with a more chronic onset (weeks to months) and treated with steroids. Both have high levels of protein in the CSF but CIDP has motor features predominating.
What’s the acute treatment for cluster headaches?
- 100% oxygen (80% response rate within 15 minutes)
- subcutaneous triptan (75% response rate within 15 minutes)
Prophylaxis for cluster headache
Verapamil
What are the features of Wernicke’s encephalopathy?
Triad:
- nystagmus (the most common ocular sign)
- ophthalmoplegia
- ataxia
- confusion, altered GCS
- peripheral sensory neuropathy
What does vertical nystagmus indicate?
Suggestive of a central cause of vertigo. Additionally, patients usually cannot stand without support, even with the eyes open.
What’s the increased risk of Bell’s palsy for pregnant women?
3 times
If you can’t do an MRI for degenerative cervical myelopathy how should you investigate?
CT myelogram
A 71-year-old man is reviewed following an ischaemic stroke. He is known to be intolerant of clopidogrel. What is the most appropriate therapy to help reduce his chance of having a further stroke?
Aspirin + dipyridamole lifelong
Following an ischaemic stroke when would you give someone a statin?
if the cholesterol is > 3.5 mmol/l
What tests would you do in those under 55 who have had an ischaemic stroke with no obvious cause of a stroke?
Autoimmune and thrombophilia screening
Which drugs are common precipitants of myasthenic crises?
Penguins quite like battered perch and anchovies
- penicillamine
- quinidine, procainamide
- lithium
- beta-blockers
- phenytoin
- antibiotics: gentamicin, macrolides, quinolones, tetracyclines
Which type of motor neuron disease carries the worst prognosis?
Progressive bulbar palsy
Which tests are done to confirm brain death?
- absent response to supraorbital pressure
- pupillary reflex
- corneal reflex
- oculo-vestibular reflex
- cough reflex
- no spontaneous respiratory effort
What are the first line investigations for patients with a suspected diagnosis of vestibular schwannoma?
audiogram and gadolinium-enhanced MRI head scan
What blood test would you do to differentiate a seizure from a pseudo seizure?
Prolactin
Elevated serum prolactin 10 to 20 minutes after an episode can be used to differentiate a general tonic-clonic/partial seizure from a non-epileptic pseudo seizure.
2-3 times higher than normal.
What are the features of subacute combined degeneration of the spinal cord?
- Damage to the posterior columns - loss of proprioception, light touch and vibration sense (sensory ataxia and a positive Romberg’s test).
- Damage to lateral columns - spastic weakness and upgoing plantars (UMN signs).
- Damage to peripheral nerves - absent ankle and knee jerks (LMN signs).
When treating a macrocytic anaemia what should you do?
Always ensure vitamin B12 levels are checked (and replenished) before giving folate for a macrocytic anaemia. Replacing folate without vitamin B12 (hinted at in this case) can precipitate subacute combined degeneration of the cord in a patient who is vitamin B12 deficient.
What’s the prognosis for childhood absence seizures?
good prognosis - 90-95% become seizure free in adolescence
Which is the best assessment tool for differentiating between stroke and stroke mimics?
Recognition of Stroke in the Emergency Room (ROSIER) scale
What proportion of relapsing remitting MS go on to develop secondary progressive MS?
around 65% of patients with relapsing-remitting disease go on to develop secondary progressive disease within 15 years of diagnosis
What’s the ROSIER score?
Loss of consciousness or syncope - 1 point
Seizure activity - 1 point
New, acute onset of: • asymmetric facial weakness + 1 point • asymmetric arm weakness + 1 point • asymmetric leg weakness + 1 point • speech disturbance + 1 point • visual field defect + 1 point
A stroke is likely if > 0
What are the causes of inter nuclear ophthalmoplegia?
MS
Stroke (in older patients)
Order an MRI to confirm
What differentiates between organic and non-organic lower leg weakness?
Hoovers sign
What should be done if a seizure isn’t under control within 30 minutes?
General anaesthetic
Where is Wernicke’s area?
Superior temporal gyrus (normally on the left)
Neuropathic pain characteristically responds poorly to opioids. However, if standard treatment options have failed which opioid is it most appropriate to consider starting?
Tramadol
What proportion of patients have an aura with migraine?
25%
When can you consider stopping anti epileptic drugs and over what time frame?
Can be considered if seizure free for > 2 years, with AEDs being stopped over 2-3 months
What can precipitate migraines?
CHOCOLATE
Chocolate Hangovers Orgasms Cheese Caffeine The oral contraceptive pill Lie-ins Alcohol Travel Exercise
What’s the chance of death following a cerebellar haemorrhage based on coma?
With coma 75% chance of death
No coma 17% chance of death
What is considered a large cerebellar haemorrhage and what are these patients at risk of? How does it affect mortality?
Patients with large cerebellar haemorrhages (>3cm) are at high risk of developing hydrocephalus and brainstem compression. This leads to rapid deterioration in conscious level and a fatality rate of 75-100%.
What test can you do to see if someone has bacterial meningitis if you’ve already given antibiotics?
latex agglutination
Characteristics of Miller Fisher GBS
Ophthalmoplegia
Ataxia
Areflexia
Anti-ganglioside GQ1b antibodies
What’s the prognosis for HSV encephalitis?
25-30%
What are the poor prognostic factors for HSV encephalitis?
- age over 30 years
- presentation in coma
- bilateral abnormalities on EEG
- high CNS viral load
- delayed treatment (4 days plus)
- abnormal CT
What are the causes of mononeuritis multiplex?
- Axonal vasculitis (Chrug strauss- rash, sinusitis, late onset asthma)
- diabetes
- drugs
- paraneoplastic syndromes
- sarcoid
- leprosy
- HIV
What specific pattern of bleeding on CT is particularly associated with angiogram negative SAH?
Perimesencephalic blood only (blood confined to the cisterns around the midbrain) since perimesencephalic SAH is the most common cause of angiogram negative SAH (see below).
