Stroke

Question 1

Explain recovery from stroke

Answer 1

Ischaemic vs haemorrhagic recovery: each have differing mechanisms by which the body initially responds to the stroke

CNS - nerves do not have capacity for neural regeneration following an injury; patients recover via neuroplasticity
PNS - nerves do have capacity for neural regeneration following injury

Question 2

What is the structure of the Circle of Willis

Answer 2

2 vertebral arteries - pass through transverse foramina of cervical vertebrae and join in front of brainstem → Basilar Artery; Basilar Artery divides → 2 Posterior Cerebral Arteries → connect to MCAs by 2 small Posterior Communicating arteries → back section of Circle of Willis

2 internal carotid arteries - pass in front of neck & divide to form Anterior and Middle Cerebral Arteries; 2 anterior cerebral arteries (ACAs) join anteriorly via the Anterior Communicating Artery → front section of Circle of Willis

Question 3

What are other related problems in stroke patients

Answer 3

1. Disorders of emotion - possibly affected limbic system thus hyperemotional and labile (tearful)
2. Dysphagia - very common in early stroke
   a. Delay / absent swallow reflex (potentially leads to food going down lungs causing aspiration pneumonia)
3. Incontinence - both bowel and bladder in early stages (no stimulation of muscles in bowel or bladder), where standing up may cause incontinence
4. Secondary musculoskeletal problems - sublux shoulder (GH j prone to damage), other MSK problems if patient falls (incidence of falls is 40-50%)
5. Balance / Gait problems
6. Functional difficulties
7. Social problems - particularly if they cannot communicate, life has changed post-stroke (many more limitations to socialising)

Question 4

Symptoms of stroke if infarct occurs in ACAs

Answer 4

Anterior cerebral arteries (ACAs) supply outer and middle areas of brain:
Frontal lobe - damage will lead to significant change to movement (motor cortex at back of frontal lobe) and personality changes, loss of memory of people and events, affected ability to plan and think
Medial part of sensorimotor cortex - affecting sensation and movement

Question 5

What symptoms would you get from a:

TACS – Total anterior circulation stroke

Answer 5

Middle and Anterior Cerebral arteries affected
All three of the following need to be present:
- Unilateral weakness (and/or sensory deficit) of the face, arm and leg
- Homonymous hemianopia
- Higher cerebral dysfunction (e.g dysphasia, visuospatial disorder)

Question 6

What is the main descending pathway?

Answer 6

The Cortico-spinal Tract = main descending pathway - 80% fibres cross to contralateral side at medulla, synapses at alpha motor neurone at specific spinal cord level, in turn passes motor information to peripheral (lower motor nerve) motor nerve to muscle

Question 7

What symptoms would you get from a:

POCS – Posterior circulation stroke ?

Answer 7

Cortical stroke in posterior cerebral artery, basilar artery, vertebral arteries
ONE of the following must be present:
•Cranial nerve palsy and a contralateral motor/sensory deficit
•Bilateral motor/sensory deficit
•Conjugate eye movement disorder (e.g. horizontal gaze palsy)
•Cerebellar dysfunction (e.g. vertigo, nystagmus, ataxia)
•Isolated homonymous hemianopia

Question 8

What healthy lifestyle advice can we give to reduce these risk factors of CVD

Answer 8

there are a few which we can influence and we will often give advice to patients with regards to:
•Ensuring that they take BP medication as directed. Blood pressure management is very important to reduce the risk of further strokes.
• Ensuring people with diabetes have support in place to ensure they are managing their blood sugars correctly.
•Smoking cessation advice: smoking dramatically increases the risk of stroke and reduction or abstinence of smoking at any time reduces the risk accordingly.
•Healthy eating advice in order to reduce cholesterol and reduce salt intake which can positively impact maintaining healthy arteries.
•Keeping active and maintaining fitness at a level appropriate to the patient, with consideration made according to each individual patient we treat.

Question 9

What is the blood supply to the brain called?

Answer 9

The Circle of Willis

Question 10

What is the time frame in which a person must present to hospital to ensure they are able to receive thrombolysis for an Ischemic stroke?

Answer 10

4 hours

Question 11

Where does most of the motor information originate in the brain?

Answer 11

Motor Cortex in the posterior Frontal Lobe

Question 12

Define neuroplasticity

Answer 12

The adaptive capacity of the CNS and its ability to modify its own structural organisation and functioning.

Neuroplasticity refers to an array of mechanisms that contribute to neuronal reorganisation and is thought to be the underlying principle by which post stroke recovery occurs.

Question 13

What are the four main symptoms of a stroke and where in the brain would damage lead to these symptoms?

Answer 13

• Motor - Pre-motor Area, Supplementary Motor Area and Primary Motor Cortex in the posterior frontal lobe
• Sensory - Primary Somatosensory Cortex (S1) in anterior parietal lobe adjacent to posterior frontal lobe (postcentral gyrus)
• Speech - Broca’s area (usually in left frontal lobe) Wernicke’s area (posterior superior left temporal lobe)
• Cognitive - frontal, parietal, temporal and occipital lobes

Question 14

What is role of PT in stroke treatment

Answer 14

Primary goals are to prevent complications, minimise impairments and to maximise function

Question 15

Main speech symptoms seen in stroke

Answer 15

1. Dysarthria - slurred speech
2. Expressive dysphasia = Damage to Broca’s area; Usually associated with Rt hemiplegia; Lose ability to produce speech
3. Receptive dysphasia = Damage to Wernicke’s area in temporal lobe; Lose ability to understand speech
4. Global aphasia - complete lack of speech

Question 16

Define stroke

Answer 16

Also known as a cerebrovascular accident (CVA), is the rapid loss of brain function(s) due to disturbance in the blood supply to the brain. This can be due to ischemia (lack of blood flow) caused by blockage (thrombosis, arterial embolism), or a haemorrhage (leakage of blood).

Seen by rapidly developing clinical signs or symptoms of focal and at times global loss of cerebral function lasting more than 24 hours or that lead to death, with no apparent cause other than vascular

Question 17

What are the 9 risk factors for CVD

Answer 17

• Age
• Hypertension (systolic >160mmHg; diastolic >95mmHg)
• Ischaemic heart disease
• AF
• High blood cholesterol
• Diabetes mellitus
• High salt diet
• Smoking
• Contraceptive pill (containing oestrogen)

Question 18

What are the 9 clinical features of stroke

Answer 18

Hemiparesis is a slight weakness/ loss of strength due to paralysis on one side of the body.

Hemiplegia is a severe or complete loss of strength or paralysis on one side of the body.

Spasticity “a motor disorder charcterised by a velocity dependent increase in tonic stretch reflexes that result from abnormal intra-spinal processing of primary afferent input” (Young, 2004)

Low Tone results from reduced ability of the muscle to move against gravity and produces little to no resistance to passive movement.

Receptive Dysphasia is the inability or difficulty in understanding speech.

Expressive Dysphasia is difficulty in the production of language, inability of difficulty selecting language appropriately in order to communicate.

Ataxia is the incoordination of movement and the lack of smooth, coordinated movement.

Apraxia is the loss of the ability to select and sequence fine and gross motor skills. There are different types of apraxia which affect stroke patients is different ways.

Agnosia is the inability to recognise objects and understand what objects are used for (visual, astereognosis, auditory).

Neglect is a severe inattention to affected limb or side of body affected by stroke. Includes visual avoidance of that side, in serve cases unable to turn head and eyes past mid point. Patients fail to attend to stimuli on affected side.

Question 19

Meninges of the brain

Answer 19

Immediately covering the brain = pia (mother) mater (covering) layer; Pia mater is a very thin layer and is “mother cuddling the brain”

Next layer = arachnoid (spider appearance) mater; Arachnoid mater has all the capillaries that supply outside of the brain in this layer thus looks like spider

Final layer = dura (durable) mater; Dura mater is very robust and strong that helps to holds the brain in place

Question 20

What are the two main types of stroke?

Answer 20

Ischaemic (80%) - Most common type of Stroke caused by a blood clot which blocks the flow of blood and therefore oxygen to brain tissue. Blood clots typically form in areas where arteries are narrowed or blocked due to as plaques as a result of atherosclerosis. Blood clots can be: atheroma of cerebral artery, thrombosis (blood clot in the brain or neck), embolism (blood clot from somewhere else that has moved and now blocks a blood vessel in the brain or neck). Classified by Bamford (Oxford) classification - according to site and extent of lesion

Haemorrhagic stroke caused by a weakened vessel that ruptures and bleeds into the surrounding brain such as a bleeding aneurysm, an arteriovenous malformation (AVM), or an artery wall that breaks open which results in damage to cerebral tissue leading to necrosis. The blood accumulates and compresses the surrounding brain tissue

Question 21

What symptoms would you get from a:
LACS – Lacunar stroke (deep penetrating arteries) ?
(ONE of the following must be present)

Answer 21

Subcortical stroke - small vessels affected
No loss of higher cerebral function.
One of the following needs to be present for a diagnosis of a LACS:
- Pure sensory stroke
- Pure motor stroke - unilateral weakness of face and arm, arm and leg or all 3
- Senori-motor stroke
- Ataxic hemiparesis

Question 22

Main motor symptoms that are seen in stroke

Answer 22

Alterations in tone
a. Low tone - flaccidity; relates to lack of stimulation to muscles
b. High tone – spasticity (30-40% post stroke; 5% of these will develop it in the first 10 days post-stroke)
Ataxia - lack of co-ordination (Trunk ataxia, upper limb ataxia, lower limb ataxia or all)
Weakness - relates to how atrophied or hypertrophied a muscle is
Asymmetry
Loss of normal movement patterns - due to asymmetry
Loss of postural adjustments - loss of balance
Compensations - “to counterbalance”

Question 23

How does a motor pathway create movement?

Answer 23

Descending motor (efferent) signals are sent from the brain to lower motor neurones which innervate muscles to create movement

CVA can damage any descending pathway

Question 24

Main cognitive symptoms seen in stroke

Answer 24

1. Perceptual Problems
   a. Agnosia (parietal/ temporal / occipital (memory storage)) - Inability to recognise objects when using a specific sense
   i. Astereognosis -inability to identify objects without looking at them (opposite of stereognosis)
   ii. Visual Agnosia - cannot recognise objects; relates to ability find the word and function for the object (receptive dysphasia - damage to Wernicke’s area)
   iii. Auditory Agnosia - cannot recognise voices of others - can be dangerous, i.e. not recognising a fire/smoke alarm
   iv. Olfactory agnosia - inability to recognize odors - can be dangerous, i.e. not smelling a gas leak, fire
   b. Depth perception - relates to driving - patients post-stroke will not be allowed to drive for at least 1 month and some will need proper assessment to check on visual perception to ensure they can drive safely. In clinic will be noticed by hitting walls
2. Apraxia (frontal/ parietal lobes) - difficulty with the motor planning to perform tasks or movements that they understand, i.e. placing tea bag in kettle or incorrect order of getting dresses.
3. Anosognosia (not common; right parietal lobe typically) - patient not recognising that have had a stroke
4. Inattention/neglect (right parietal lobe)
   a. Visual - when they do not recognise affected side of field as they cannot see through it
   b. Sensory - when they do not recognise affected side of body as there is no sensation
   c. Cognitive - when they do not recognise limbs as their own
   d. More common with left hemiplegia
   e. Patients fails to attend to stimuli from the left side
   f. Poor prognosis if persists
   g. Results in many functional problems - self-care, eating, dressing, walking
5. Behavioural/emotional changes (frontal lobe)
6. Organisation/sequencing and memory (temporal lobe)

Question 25

Symptoms of stroke if infarct affects MCAs

Answer 25

Middle cerebral arteries (MCAs) - most commonly affected in CVA
○ Most of the outer (lateral) surface
○ Sensorimotor cortex (front of parietal lobe) - if affected (plus motor cortex at back of frontal lobe) will have significant changes in sensation and movement
○ Basal ganglia (store movement memories) - if affected issues with initiating movement and producing movement patterns; affected in PD
○ Internal capsule (below basal ganglia) - where ascending and descending pathways pass through; if damaged will have significant damage to sensation and movement
○ Broca’s area (on left of frontal lobe) - involved in speed thus damage = expressive dysphasia

Question 26

Symptoms of stroke if infarct affects PCAs

Answer 26

Posterior cerebral arteries (PCAs) supply posterior areas of the brain
○ Occipital lobe - if damaged will have significant changes to eyesight, issue with processing visual cues
○ Medial aspect of temporal lobe - if damaged problems with processing hearing, speech and understanding speech (receptive dysphasia - Wernicke’s area)
○ Thalamus (sensory-relay station) - if damaged sensation is affected

Question 27

4 Types of haemorrhagic stroke

Answer 27

1. Intracerebral Haemorrhage - within cerebrum
   • Bleeding into deeper parts of brain
   • Associated with hypertension
   • Arterial walls weaken leads to micro-aneurysms develop ultimately rupture and bleed
   • Severe headache & vomiting
2. Subarachnoid Haemorrhage - under arachnoid mater in subarachnoid space
   • Bleeding into subarachnoid space
   • Associated with sudden intense headache vomiting, neck stiffness & loss of consciousness
   • Approx 10% die within 1st 2 hours 40% will die within 2 wks
3. Subdural Haemorrhage - under dura mater
   • Bleeding into the subdural space
   • Usually caused by trauma
   • May be an interval between injury & symptoms
   • Headache, drowsiness leads to stupor leads to hemiparesis ultimately coma
4. Extradural Haemorrhage - outside of dura mater
   • Bleeding into extradural space
   • Caused by severe trauma – tearing of meningeal artery

Question 28

Define Transient Ischaemic Attack (TIA) or mini stroke

Answer 28

During a transient ischaemic attack blood flow to a specific area of the CNS is impaired resulting in acute neurological symptoms. A TIA is a sign that part of the brain is not getting enough blood, and there is a risk of a more serious stroke in future. It used to be considered symptoms lasting less than 24 hours but now the timeframe is a lot shorter – one to two hours.

Question 29

What symptoms would you get from a:
PACS – Partial anterior circulation stroke ?
(TWO out of three must be present)

Answer 29

Partial cortical stroke in middle/anterior cerebral artery areas

• Unilateral weakness (and/or sensory deficit) of the face, arm and leg
• Homonymous hemianopia
• Higher cerebral dysfunction ( e.g dysphasia, visuospatial disorder)

Question 30

Symptoms of stroke if basilar artery affected

Answer 30

Basilar artery - Most dangerous CVA:
All of the brainstem - if damaged leads to issues with heart, respiratory control centres
Cerebellum - if damaged leads to ataxic movement
Nuclei of cranial nerves - facial nerve VII damage = facial nerve palsy that causes a drop on one side of the face, mimicking a stroke, vagus nerve X = damage to autonomic system leading to issue with heart function (life/death situation); Peripheral nerves therefore can heal; Facial nerve VII usually infected or inflamed causing facial nerve palsy - will resolve itself

Question 31

Main sensory symptoms that are seen in stroke

Answer 31

1. Sensory impairment
   a. Impaired cutaneous sensation - can be low (anaesthesia) or hypersenstivity or altered sensation (parasthesia)
   b. Astereognosis - inability to identify objects without looking at them (opposite of stereognosis)
   c. Proprioceptive impairment - lack of awareness of where limbs are in space (picked up through muscle spindles, joint receptors, golgi tendons, etc)
2. Visual problems
   b. Homonymous Hemianopia - loss of one side of visual field

Question 32

What are the neuroplasticity mechanisms

Answer 32

1. “Unmasking” of dormant pathways provides changes in synaptic strength
   a. Many neural pathways lie dormant naturally – these dormant pathways become more effective once the primary pathways that were previously being used are removed or incapacitated following disease or injury
   b. These pathways increase in synaptic strength with continued use
   c. (Synapses not normally used, following an injury (stroke) are then called upon and strengthened with continual use)
2. Collateral sprouting provides formation of new synapses
   a. Prior to collateral sprouting - Damage to axon/nerve cell occurs, causes nerve degeneration - means unable to deliver AP which disrupts nerve signals from being delivered
   b. Formation of new synapses via collateral sprouting from intact nerve cells to where damage has occurred causing denervation (stops pain transmission)
   c. This occurs in conjunction with neural re-organisation and as a response to demand from intact cells to denervated region

Question 33

What is the role of a PT in promoting neuroplasticity following stroke

Answer 33

Key points to promote plasticity

1. Using a particular neural pathway will make it stronger
2. Practicing an activity enhances and promotes learning
3. Plasticity occurs in response to demand

As Physiotherapists we can maximising repetition through:

1. Interesting and varied activities
2. Motivation - e.g involvement of family and friends, goal orientated working
3. Home programmes – Being in a stimulating environment increases neural plasticity
4. Education and clear communication
5. Aerobic exercise promotes plasticity – exercise prescription post stroke must be specific and safely identified to suit an individual’s needs.