Neurology Flashcards
Define ‘Ischaemic Stroke’
An episode of neurological dysfunction
caused by focal cerebral, spinal, or retinal
infarction.
Definition of ‘intracerebral haemorrhage’
A focal collection of blood within the brain
parenchyma or ventricular system that is not caused
by trauma.
Definition of stroke caused by intracerebral haemorrhage.
Rapidly developing clinical signs of neurological
dysfunction attributable to a focal collection of blood
within the brain parenchyma or ventricular system that
is not caused by trauma.
Causes of intracranial bleed?
Small vessel disease, amyloid angiopathy, abnormalities in blood vessels. blood clotting deficiencies, haemorrhagic transformation of a infarct, tumours, drugs usage: cocaine, amphetamine.
Hyper-acute stroke treatment
1) IV Thrombolysis. Within 4.5 hours of symptom onset.
2) Thrombectomy
3) Admission toa stroke unit
What is an aneurysm?
A dilation of an artery. Happens in haemodynamic stress.
What are the predisposing factors for aneurysmal SAH?
Smoking, female sex, hypertension, positive fmaily history, ADPCK, Ehlers Danlos, Coarctation of aorta.
Factors that affect consciousness
Trauma, elevated ICP, fever, hypothermia, seizure, sepsis, medications, hypoxia, hypercapnia and more.
What is consciousness?
Reflects level of arousal (RAS) and presence of cognitive behaviour (cerebral hemispheres).
Most common cause of radial nerve palsy and symptoms?
Entrapment at spiral groove-‘Saturday night palsy’. Wrist and finger drop, usually painless.
Most common cause of ulnar nerve palsy and symptoms?
Entrapment at ulnar groove. May be history of trauma at elbow. Sensory disturbance and weakness. Usually painless.
Most common cause of median nerve palsy and symptoms?
Entrapment within carpal tunnel at wrist. History of intermittent nocturnal pain, numbness and tingling. weak grip”. Positive Tinel’s sign/ Phalen’s test.
Most common cause of median nerve- anterior interosseous branch- palsy and symptoms?
Trauma to forearm. History of forearm pain, “weak grip” of keys, unable to make okay sign.
Most common cause of femoral nerve palsy and symptoms?
Haemorrhage/trauma. Weakness of quadriceps, weakness of hip flexion, numbness in medial shin.
Most common cause of common peroneal nerve palsy and symptoms?
Entrapment at fibular head. Possible history of trauma, surgery or external compression. Acute onset foot drop and sensory disturbance. Usually painless.
What is mononeuritis multiplex?
Simultaneous or sequential development of damage to 2 or more separate nerves. Common causes: diabetes, vasculitis, rheumatological, infective, sarcoidosis, lymphoma.
What is a primary headache?
When the headache and it’s associated features is the disorder (no underlying cause) eg. migraine, tension-type headache, cluster headache.
What is a secondary headache?
The headache is secondary to an underlying cause. eg. Subarachnoid haemorrhage, space-occupying lesion, meningitis, temporal arteritis etc.
‘Red flag’ features of headaches
SNOOPT.
S- Systemic symptoms
N- Neurological symptoms or signs
O- Older age at onset
O- Onset is acute (under 5 minutes)
P- Previous headache history is different/absent
T- Triggered headache (valsalva or posture)
What is a ‘Medication overuse headache’ (MOH)?
Headache lasting over 15 days per month associated with frequent use of acute relief mediations eg. NSAIDs, paracetamol, opioid. Patients advised to take acute treatments no more than 2-3 times per week to prevent MOH.
What is a chronic migraine?
Headache on more than 15 days per month.
What is a ‘thunderclap headache?’
Abrupt-onset of severe headache which reaches maximal intensity <5 minutes (and lasts >1hr). Should be considered subarachnoid haemorrhage (SAH) until proven otherwise. “worst headache of my life” “like being hit over the head”.
What are the causes of a thunderclap headache?
Subarachnoid haemorrhage unless proven otherwise. Other causes: intracerebral haemorrhage, arterial dissection, cerebral venous sinus thrombosis, bacterial meningitis, spontaneous intracranial hypotension.
Lumbar puncture for subarachnoid haemorrhage?
Needs to be performed after at least 12 hours to look for the presence of xanthochromia- a blood breakdown product.
What is the normal intracranial pressure?
ICP normally 7-15mmHg.
Why is raised ICP a problem?
CPP=MAP-ICP. Global brain perfusion is reduced when ICP is elevated and cerebral metabolism is reduced.
What history findings make you think someone has a raised pressure headache?
Worse on lying flat, worse in the morning, persistent N&V, worse on valsalva (eg. coughing, laughing, straining), worse on physical exertion, transient visual obscurations with change in posture.
What will you find on examination in someone with a raised pressure headache?
Papillodema, impaired visual acuity/colour vision, restricted visual fields/blind spot, 3rd nerve palsy, VIth nerve palsy, focal neurological signs.
What are the causes of raised ICP?
Mass effect, increased venous pressure, obstruction to CSF flow/absorption, idiopathic.
What are the features of lower CSF pressure headaches?
Headache worse on sitting/standing up and relieved by lying over. Results from CSF leakage, loss of CSF volume causes traction on meninges, cerebral/cerebellar veins and CN V, IX and X.
What are the causes of low CSF pressure headaches?
Post lumbar puncture- affects up for 1/3 cases, 90% develop with 3 days, most resolve spontaneously. Spontaneous intracranial haemorrhage- results from spontaneous dural tear.
What is Multiple Sclerosis?
Idiopathic inflammatory demyelinating disease of the CNS. Acute episodes of inflammation are associated with focal neurological deficits.
What are the 4 subtypes of MS?
- Relapsing remitting MS
- Primary progressive MS
- Secondary progressive MS
- Benign MS
What syndromes can develop into MS?
- Optic neuritis
- Clinically isolated syndromes
- Transverse myelitis
- Radiologically isolated syndromes
What is optic neuritis?
Painful visual loss that comes on over a few days. 30% develop MS by 5 years, 50% develop MS by 15 years.
What is transverse myelitis?
Inflammation of the spinal cord that leads to weakness and sensory loss. Incontinence can be the only symptom. Many other causes than MS.