Neuro Info Flashcards
Anatomy and Physiology of the Brain
2 cerebral hemispheres connected by corpus callosum (left controls right body, right controls left body).
3 Layers:
1. Dura Mater: most external, thick, tough.
- Periosteal, (inner surface of skull)
- Meningeal (outermost brain cover)
2. Arachnoid: separated from dura by subdural space, beneath this is subarachnoid space, spanned by threadlike arachnoid extensions anchoring it to the pia mater underneath.
Contains CSF and all major cerebral arteries and veins.
Fine and elastic so the vessels are poorly protected.
3. Pia Mater
Has micro-vessels that supply nutrition directly to the cortex.
Protect CNS structures, contain CSF and form partitions in the skull.
Frontal Lobe Anatomy
- Front of central sulcus
- Controls production of movement (concerned with reasoning, planning and speech).
- Contains Broca’s area (damaged: expressive dysphasia).
Supplied by:
- Internal carotid artery
- Anterior and middle cerebral artery
Parietal Lobe Anatomy
- Behind central sulcus
- Deals with sensory info (touch, pressure, pain, temp) and perceives proprioception (provides start point)
- If disrupted: balance issues
Supplied by:
- Internal carotid artery
- Anterior and middle cerebral artery
Occlusive Stroke
85% of strokes, lifestyle affects
Pathological Process:
1. Atheroma forms
Obstruction of build up of fatty deposits = blockage = narrowing the stenosis of lumen = increased pressure of the blood flowing.
2. Thrombus forms
Due to turbulent flow as blood struggles to flow through atheroma.
3. Embolus breaks off clot
Which moves further into the brain and gets stuck in smaller arteries of the brain.
4. Brain tissue starts to die
As blood supply has reduced and there is a lack of oxygen for the brain to function.
Occlusive Stroke
Anterior and Middle Cerebral Artery Signs and Symptoms
Anterior:
Behavioural problems (frontal lobe)
Sensory loss
Contralateral monoplegia (frontal lobe)
Middle:
Hemianopia (vision impairment)
Dysphasia
Dysarthria (difficulty articulating speech - muscles)
Cognitive/perceptual problems
Dense contralateral hemiplegia
Low tone initially due to hyposensitivity of stretch reflex
- Presentation: Usually sudden onset, may develop rapidly, may/may not lose consciousness
Occlusive and Haemorrhage Stroke Lifestyle Factors
Smoking, diabetes, obesity, alcohol, lack of activity, hypertension (when blood pressure is consistently raised)
Occlusive: these factors can cause stroke
Haemorrhage: these factors increase the chance of stroke as already have an aneurysm
Intracerebral Haemorrhage Stroke
9% of cases, younger, normotensive patients, congenital
Pathological Process:
1. Hypertension
Caused by degeneration of small penetrating arteries in the brain leading to bleeding in deep areas e.g. basal ganglia, thalamus
2. Arterio-venous Malformation (AMV)
Abnormal connection between arteries and veins, bypassing the capillary system.
Intracerebral Haemorrhage Stroke
Signs and Symptoms
Presentation
Hemi paresis/plegia
Low tone
Visual and speech problems
Sensory Loss
Presentation:
Sudden onset
Severe headaches
Loss/deterioration of consciousness
Subarachnoid Haemorrhage Stroke
6% of cases, cerebral arteries lie between arachnoid and pia mater meninges, congenital
Pathological Process:
1. Aneurysm
Thinning and stretching of vessel wall and constant blood flow through, forms a sac.
2. Bleeding
Into subarachnoid space, which spreads across whole cortex and spinal column
Subarachnoid Haemorrhage Stroke
Signs and Symptoms
Presentation
Hemi paresis/plegia Low tone Dysphasia Sensory loss Cognitive and perceptual problems
Presentation:
Sudden onset, headaches, stiff neck, vomiting
Infarction immediate or develop over days
Management of Stroke
Hospital admission – CT scan, not immediately visible, site and size of lesion, confirm diagnosis, occlusive or haemorrhagic – CXR, ECG, BP, blood cholesterol – Ultra Sound neck arteries – Echocardiogram heart scan
Haemorrhage Stroke Medical Management
Optional Info
Bed rest, analgesia
Maintain vital signs, ICU, HDU
CT scan, Angiogram
Aneurysm repair
– Clipping neck, wrapping, trapping – craniotomy
– Embolisation, coil or glue – angiography
Timing crucial, around 3 days from onset
Occlusive Stroke Medical Management
Optional Info
- Thrombolytic agents (Streptokinase) Within 3-6 hours - Anticoagulant therapy (Warfarin / Heparin) If cardiac source of emboli, not in haemorrhage - Prevention of further CVA Aspirin Lower BP Lower cholesterol levels Lifestyle advice
Assessment Interventions
Movements:
(Looking for PQRRS)
- Active: assess muscle strength
- Passive: assess ROM available
- Isotonically test: more functional, through range
- Accessory: help decrease tone
Lower limb: foot (fascia, interphalangeal and metatarsal joints)
Upper limb: hand (palmar aponeurosis, fascia, interphalangeal/metacarpal joints)
Postural Sets:
- Supine, prone, sitting, side lying
- Isolates problem
Sensory Testing
Assessment Intervention
Sensory Testing - Ascending tracts
Ascending tracts: sensory, carry sensations from periphery to thalamus.
1. Sharp/blunt
Sharp: lateral spinothalamic tract
Blunt: anterior spinothalamic tract
- Hot/cold
Lateral spinothalamic tract - Positioning affected limb with eyes closed
Lower limb: medial dorsal column
Upper limb: lateral dorsal column
