Neurology 2 Flashcards
At which level do the nerve roots stop exiting the spinal cord above the vertebrae and instead exit below?
C7
*remember C7 has above and below creating a C7 nerve root and C8 nerve root
What are the motor symptoms of radial compression:
Weakness in:
- Wrist extension
- finger extension
- Elbow flexion mid pronation (Brachioradialis)
*usually lack of pain
There are two main sites that one can develop ulnar nerve palsy, where are these?
Medial epicondyle of the humerus / cubital tunnel
Guyon canal
*paradoxically gets worse the more distal the lesion
List some drugs which commonly cause length dependent polyneuropathy:
Amiodarone
Cisplatin
Isoniziade
Alcohol
List some causes of length dependent peripheral neuropathy?
Diabetes
Alcohol
Nutrition
Immune
Drugs
HIV
Paraneoplastic
Critical illness
What investigations should be done into peripheral neuropathy and why?
FBC
- MCV - B12? Alcohol?
HbA1c/ OGTT
U&Es
- electrolyte imbalance
TFTs
- can cause peripheral neuropathy
B12/ Folate
Electrophoresis
- myeloma
- if proximal and peripheral signs then:
- LP
- EMG/ nerve conduction studies
Name a finding seen on nerve conduction studies which suggest demyelination?
Temporal dispersion
What complication of cervical myelopathy can make surgery very difficult?
Ossification of the posterior longitudinal ligament
What is the definitive management of lumbar radiculopathy? (sciatica)
Lumbar microdiscectomy
List some signs seen on clinical examination which would suggest the cause of vertigo is centrally caused?
Negative head impulse test
Bidirectional Nystagmus
Vertical skew (nystagmus vertically)
- other signs
- ataxia
- passed pointing
- changes to speech
List some causes of Horner’s syndrome listing whether they are central (1st order neuron), preganglionic (2nd order neuron) or post ganglionic (3rd order neuron):
1st order:
- Stroke (Weber’s syndrome)
- Brainstem tumour
- MS
2nd order:
- Pancoast tumour
- Thyroidectomy
- Trauma
- Cervical rib
3rd order:
- Carotid artery dissection
- Cavernous sinus thrombosis
- Posterior communicating artery aneurysm
- cluster headache
What clinical sign can help localise where the lesion is in Horner’s syndrome and why?
Anhidrosis
If lack of sweating is present it localises the lesion to either the:
- brainstem (1st order neurons)
- Preganglionic (2nd order)
this is because these nerves are the only ones that branch off to supply the sweat glands. In other words - the 3rd order neurons to the eye are not associated with the sweating
If a patient presents with signs and symptoms suggestive of a posterior stroke, but the CT negative what does this mean?
Which vessel is typically affected?
CT is not sensitive for posterior strokes therefore is not reliable.
MRI is more sensitive
Posterior Inferior Cerebellar Artery
- most commonly affected causing lateral medullary syndrome
What is the acute sign seen on CT following an ischemic stroke?
Hyperintense vessel sign
- can see the clot in the vessel
Why is it so important to make sure that a person with Parkinson’s disease received their medication at the correct dose at correct time?
Avoid development of
- Parkinson’s Hyperreflexia syndrome
Sudden withdrawal of medication can lead to acute dystonia and neuroleptic malignant syndrome
What other areas of management must be considered in someone with Parkinson’s other than medication?
Bone health
Exercise
Psychology/ support
Advance care planning
How is Lewy body dementia differentiated between Parkinson’s associated dementia?
If dementia is onset is within 12 months then this suggests Lewy body dementia
in other words
- early onset dementia
What is the main side effect of Enzyme inhibitors such as COMT, used in Parkinson treatment?
Diarrhea
What are the Parkinson plus syndrome and list some features of them:
Progressive Supranuclear Palsy:
- Postural instability
- Vertical gaze palsy
- Truncal rigidity
Multisystem Atrophy:
- Early autonomic signs (hypotension, incontinence, falls)
- Cerebellar signs
Corticobasal degeneration
- Akinetic limb loss affecting one limb
- progressive aphasia
- Sensory loss
Lewy body dementia
- Early onset dementia
- fluctuates in cognition
Vascular parkinson’s
- Predominant lower limb symptoms >3 years
What are some of the red signs with Parkinson’s disease that may make you query diagnosis:
Rapid impairment requiring wheelchair within 5 years
No progression of motor symptoms over 5 years
Marked bulbar dysfunction within 5 years
Severe autonomic dysfunction
UMN signs
Dystonic Anterocollis within 10 years
In suspected bacterial meningitis the first step in management is IV antibiotics. what additional antibiotics should be given to those >60 years old? and what additional symptoms/ features may be seen?
Amoxicillin
- cover Listeria monocytogenes
Listeria monocytogenes usually has:
- prodromal headache of 2-3 days
- Low sodium - hyponatremia
- confusion
**babies <3 months are also given amoxicillin to cover for listeria
Give some differentials for raised intracranial pressure in a young person:
Tumour
Venous cerebral sinus thrombosis
Idiopathic intracranial hypertension (would not cause a seizure)
What are the presenting symptoms and How do you diagnosis a venous cerebral sinus thrombosis? and what are some risk factors, and what is the treatment?
Headache Vomiting Seizure Papilloedema Periorbital oedema
CT venography/ MRI venography
- Oral contraceptive
- pro-coagulative/ thrombophilia
- nephrotic syndrome
- Pregnancy
- Dehydration
- Mastoiditis/ Sinusitis/ Otitis
Treatment:
- Anti-coagulation
Highlight the symptoms you would expect from a seizure affecting particularly lobes:
Frontal:
- motor
- Personality
Temporal
- Automatisms
- dejavu
Parietal:
- sensory
Occipital
- visual (explosion of light or colour)
If someone presents with suspected seizure, what is the first investigation that should be ordered?
ECG
- to rule out cardiac origin
BM
- dont ever forget glucose
What is the fetal elliptic complication that can occur, and what are some associations with it?
Sudden Unexpected Death in Epilepsy
- usually occurs after a GTC in the patients sleep
Associations include:
- poorly controlled epilepsy
- Frequency GTC attacks
What is the distinguishing feature of peroneal nerve palsy vs sciatic damage causing foot drop?
Peroneal damage they are still able to invert the foot as this is not supplied by the peroneal branches.
Following a TIA - how long till one can drive?
1 month if symptom free.
- do not need to inform DVLA
In terms of voluntary movement and tremor in Parkinson’s - what would you expect?
Expect the tremor to improve upon voluntary movement
What symptom is more common in children with migraines?
Gastrointestinal symptoms
- N&V
What are the signs and symptoms of cerebellar damage?
DANISH
D- Dysdiadochokinesia A - Ataxia N - Nystagmus I - Intentional tremor S - Staccato speech H - Hypotonia V - Vertigo
What are the causes of Cerebellar signs?
PASTRIES
- Posterior Fossa Tumours
- Alcohol
- Stroke
- Trauma
- Rare - paRaneoplastic
- Inherited - Friedreich’s ataxia
- Epilepsy drugs - Sodium valproate and phenytoin
- Sclerosis - MS
If a patient has a 3rd nerve palsy along with a headache or pain in the eye, what must be considered?
Posterior communicated artery aneurysm
Diagnosed via a CT angiogram
What is meant by conning?
Tonsillar herniation through the foramen magnum compressing the brain stem
List several causes of reduced GCS in a patient with alcohol abuse?
Hypoglycaemia
Delirium Tremens
Meningitis
Hepatic encephalopathy
Head injury - from falling
Alcohol intoxication
Other substance abuse
Which nerve root causes finger abduction weakness?
C8 - T1
Abduction is carried out by ulnar nerve
Over what period of time can consideration for anti-epileptic medication be stopped?
Seizure free for 2 years, stopping over 2-3 months
What is the inheritance pattern of an essential tremor?
Autosomal dominant
What is the usual immediate management of a TIA and when would this not be advisable?
300mg immediately.
Not advisable if already on anti-thrombotic medication.
Need urgent CT to rule out bleed.
What is the drug of choice for nausea in Parkinson’s disease (usually caused by the medications)
Domperidone
- Doesn’t cross the BBB
What are your differentials for causing cauda equina syndrome?
Prolapsed disc
Malignancy
Trauma - vertebral subluxation
Iatrogenic - spinal haematoma
Infection
What is the preferred anti-platelet following a stroke?
Clopidogrel
What are the ICP waveforms?
A wave:
- continually high pressure above >50mmHg caused by Intracranial lesion
B wave:
- less pressure but still pathological
C wave:
- Moves up and down in pressure. May not be pathological
What are the ways the brain can compensate to raised ICP and what additional ways can children compensate?
1st: Reduce CSF
2nd: Reduce Venous Flow
3rd: Reduce tissue space - brain herniation
Children:
- Bulging fontanelle
- Widening of the suture
What is the gold standard investigation into raised ICP and what is the management?
MRI head
+/-
Invasive ICP monitoring
Management:
- Dexamethasone *not suitable in trauma
- Mannitol or hypersaline solution
- reduce CO2, decreases vasodilation. PaCO2: 4-5
- Maintenance of BP to increase MAP over ICP
- Sedation with Propofol
- Craniectomy
- bone part can be placed in the abdomen for later fixation
What is the definition of hydrocephalus?
Excessive accumulation of CSF within the head caused by a disturbance of flow or absorption. Resulting in high pressure and dilation within the ventricular system.
What are the classifications of hydrocephalus?
Children:
- Arnold Chiari malformation - cerebella tonsils descend into the canal *associated with spina bifida
- Stenosis of the aqueduct
- Tumour obstruction
Adult:
- Posterior fossa and brainstem tumours
- SAH (arachnoid granulation disruption)
- Choroid plexus papilloma (secretes CSF)
- Normal pressure hydrocephalus (not actually normal pressure)
What are the surgical options for hydrocephalus?
- Remove cause
- Diversion of flow
- External ventricular shunt
- Endoscopic third ventriculostomy
- Shunts - Choroid plexectomy
What are the parts to a shunt used for hydrocephalus? and name the most common type:
1st: ventricular catheter
2nd: Shunt valve
3rd: Distal catheter
Ventriculo- peritoneal shunt
- other places can include into:
- pleura
- Right atrium
How does a subdural haematoma present on CT scan?
Hyperdense and make a crescent shape around the brain.
- not limited by suture lines
Appears hypodense (dark) if chronic
What drugs are given prophylactically for migraines?
Propranolol
or
Topiramate
*propranolol is preferred in females of child bearing age
What is the first line for trigeminal neuralgia?
Carbamazepine
