Bamford classification of stroke PDF

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Bamford/Oxford classification The Bamford/Oxford classification is used to subclassify ischaemic strokes. This system differentiates ischaemic strokes based on the presenting clinical features, which correlates with the cerebral territory affected.

Clinical features A stroke presents with sudden, focal neurological deficit that reflects the area of brain devoid of blood flow.

Haemorrhagic Patients with a haemorrhagic stroke are more likely to present with global features such as headache and altered mental status.      

Headache Altered mental status Nausea & Vomiting Hypertension Seizures Focal neurological deficits (dependent on location of bleed)

Anterior ischaemic stroke Patients with anterior ischaemic strokes (i.e. TACS, PACS, LACS) develop a constellation of features dependent on the extent and location of the infarct.  Unilateral weakness and/or sensory deficit: face and/or arms and/or legs  Homonymous hemianopia: visual field loss on the same side of both eyes  Higher cerebral dysfunction: dysphasia, visuospatial dysfunction (e.g. neglect, agnosia)

Classically, an isolated infarction of the anterior cerebral artery leads to contralateral leg weakness only. This is because individual areas of the motor and sensory cortex that control movement and sensation, respectively, correspond to specific areas of the body. This 'biological map' is often referred to as the 'cortical homunculus' (homunculus refers to 'little man' in Latin). The anterior cerebral artery supplies an area of the motor cortex that controls leg movement. We can see this clearly in the diagram below.

The cortical homunculus - areas of the body that correspond to the motor and sensory cortex Image courtesy of Popadius. Wikimedia commons.

Posterior ischaemic stroke The posterior circulation is composed of the vertebrobasilar arterial system. This supplies the brainstem, cerebellum and occipital cortex. Therefore, posterior strokes can affect balance, vision, and cranial nerves. POCS account for 20-25% of ischaemic strokes.  Dizziness  Diplopia  Dysarthria & Dysphagia  Ataxia  Visual Field defects  Brainstem syndromes: often seen with crossed signs* *ipsilateral cranial nerve lesions with contralateral sensory and motor limb deficits. This is because many tracts (e.g. corticospinal tracts) cross over at the brainstem (i.e. information from the right hemisphere crosses over to provide infromation to the left side of the body). This is known as decussation....