Neurology I: Demyelination, Facial Pain & Cerebrovascular Disease Flashcards
What is neurology?
The branch of medicine or biology that deals with the anatomy, functions, and organic disorders of nerves and the nervous system.
What do the different parts of the brain control?
Frontal Lobe: Motor control, concentration, planning, problem solving, speech, smell.
Parietal Lobe: Touch and Pressure, taste, body awareness, language
Temporal Lobe: Hearing, facial recognition
Occipital lobe: Vision
Cerebellum: Coordination
What do we mean when we say the cranial & spinal nerves all decussate?
Right side of the body is controlled by the left side of the brain vice versa
because the nerves cross and intersect with each other
What is tested in a neurological examination?
Tone– resistance to passive movement of a joint
Power– power is tested by comparing the patient’s strength against your own
Reflex– involuntary and nearly instantaneous movement in response to a stimulus e.g using hammer
Co-ordination– voluntary/purposeful movements
Sensation– conscious experience resulting from stimulation
What is a stroke?
A focal neurological deficit which lasts longer than 24 hours resulting from a vascular lesion.
Can have either Ischaemic stroke (blood supply is blocked and cut off to a particular area of the brain)
or
Haemorrhagic stroke (you end up bleeding into a particular area of the brain or skull due to weakened vessel walls and that causes the stroke)
80% of all stroke events are ischaemic
How can you measure a patient’s consciousness levels?
AVPU/GCS
AVPU:
A- alert (can answer questions sensibly)
V- responds to verbal commands
P- responds to a pressure or pain stimulus
U- unresponsive to any stimulus
GCS: see attached image
How can you identify a stroke?
FAST:
Face- asymmetry of the face, unilateral palsy
Arms- weakness in the arms
Speech- slurring of speech (dysarthria)
Time- phone for help
What are some symptoms of strokes?
Sudden numbness or weakness in the face, arm, or leg, especially on one side of the body
Sudden severe headache with no known cause
Confusion, trouble speaking, or difficulty understanding speech (aphasia)
Sudden trouble seeing in one or both eyes (visual field defects)
Ataxia- sudden trouble walking (gait disturbance), dizziness, loss of balance, or lack of coordination
What is a transient ischaemic attack (TIA)?
A focal neurological deficit which lasts less than 24 hours resulting from a vascular lesion; the deficit fully resolves
Temporary in nature
Requires active preventative treatment and investigation, indicates a stroke coming.
What are the risk factors for a stroke?
-Diabetes
-Cigarettes
-Obesity
-Oestrogen OCP
-Excess EtOH
-Polycythaemia (Raised haemoglobin)
-Atheroma (hypercholesterol/lipid aemia)
-Hereditable nature (family history of stroke)
-Hypertension
How can someone be affected by a stroke depending on which side was damaged?
slide 17
What are the common lesions and outcomes of a stroke? (hemiplegia)
Most common lesion - hemiplegia
From infarct of contralateral internal capsule (high-risk zone of motor & sensory fibres converging on brainstem from cerebral cortex
Middle cerebral artery territory Motor - hemiplegia arm - leg
Initially hypotonic (flaccid) with reduced reflexes
Few days spasticity supervenes - arm(flexed) & leg (Extended)
hyper reflexia & upgoing plantar (indicates UMN)
Strength recovery over weeks to months UMN VII nerve
What are the common lesions and outcomes of a stroke? (hemisensory)
Sensory - hemisensory (patchy if not so dense)
Hemianopic
(1 side vision loss (homonymous hemianopia)
Possibly apahasia
Smaller infarcts can give pure motor / sensory damage
Brainstem infarcts – complex
e.g. – pseudobulbar palsy (IX –XII #) – dysphagia etc Horner’s syndrome
What should you do in case of an acute stroke?
-Thrombolysis (Within 4 hours)- not for haemorrhagic stroke
-Clot retrieval
-Maintain BP
-ECG
-Nil by mouth- till SALT assessment
What should you do in case of a chronic stroke?
Support- Stroke unit; rehab/physio/skin care
NG feeding/laryngeal introitus care; hydration
Aids/chairs lifts/OT input/GDP OH adaptations
Look for second risk factors
Carotid atheroma (MRA/Doppler angio-flow); clotting screens (clotting syndromes/medications); hypertension
Medication- anti-platelets/anticoagulants
What is a subarachnoid haemorrhage?
Uncommon type of stroke caused by bleeding into the brain - arterial
What are the classic signs and symptoms of a subarachnoid haemorrhage stroke?
Classic “thunderclap headache” with neck stiffness
(caused by Circle of Willis Berry aneurysm rupture)
Sudden LOC (loss of consciousness- shortly after event)
Signs of meningism (e.g. photophobic)
Why do you have to act rapidly in cases of subarachnoid haemorrhage?
There’s a fast onset and it’s a high pressure bleed because it’s arterial so you have to act quickly.
How do you treat subarachnoid haemorrhage?
First MRI scan and then often neurosurgery
Clip & tie bleeder if not stopped spontaneously - this is when blood vessel is clipped and tied off
Who is typically affected by an extradural haemorrhage?
Young patients, usually involved in a head strike (either during sport or a result of a motor vehicle accident) and they may/may not lose consciousness transiently.
extradural hamemorrage - a collection of blood that forms between the inner surface of the skull and outer layer of the dura, which is called the endosteal layer.
Who is typically affected by subarachnoid haemorrhages?
older women
What happens to people with extradural haemorrhage following the injury?
Following the injury they regain a normal level of consciousness (lucid interval)
Usually have an ongoing and often severe headache
Over the next few hours they gradually lose consciousness
What type of bleed is an extradural haemorrhage?
Arterial bleed, usually middle meningeal artery damage
How does an extradural haemorrhage present in a CT/MRI?
As a convex blood mass
What is a subdural haematoma and where is it located?
It’s a collection of blood between the dura and the brain which has a slower onset and is a venous bleed
Located ‘below the dura’
When does a subdural haematoma typically occur?
Typically after a fall or if they’re on anti-coagulants
Where do the different brain haemorrhages happen?
slide 24
What is epilepsy?
A neurological disorder marked by sudden recurrent episodes of sensory disturbance, loss of consciousness, or convulsions, associated with abnormal electrical activity in the brain
Generally it’s a lifelong condition
What are the different types of epilepsy?
General, focal (simple partial)
