Part 2: Brain Blood Supply – Clinical Correlations & Stroke Syndromes!

 Now that you’ve thought about the anatomy of the brain’s blood supply, let’s explore how this knowledge helps localise strokes and other vascular syndromes.

🗺️ Arterial Territories & Clinical Impact

🔹 Anterior Cerebral Artery (ACA):

• Territory: Medial frontal/parietal lobes; corpus callosum.
• Stroke Signs: Contralateral leg weakness/sensory loss; personality changes and apathy (frontal lobe).
• Clinical Relevance: ACA strokes often cause subtle behavioural and executive function changes that might be missed unless you carefully assess cognition.

🔹 Middle Cerebral Artery (MCA):

• Territory: Lateral frontal/parietal lobes; basal ganglia (via lenticulostriate arteries).
• Stroke Signs: Contralateral face/arm weakness; aphasia (dominant hemisphere) or neglect (non-dominant).
• Clinical Relevance: MCA territory strokes are the most common in ischaemic stroke—often from atrial fibrillation-related emboli.

🔹 Posterior Cerebral Artery (PCA):

• Territory: Occipital lobe, inferior temporal lobe, thalamus, midbrain.
• Stroke Signs: Contralateral homonymous hemianopia; memory impairment; sensory loss if thalamic involvement.
• Clinical Relevance: Patients with PCA strokes may present with isolated visual field deficits, so always check for visual neglect.

🔹 Vertebrobasilar System:

• Territory: Brainstem, cerebellum, thalamus, occipital cortex.
• Stroke Signs: Cranial nerve palsies, ataxia, crossed motor/sensory findings.
• Clinical Relevance: Basilar artery occlusion can cause 'locked-in syndrome'—an emergency where the patient is conscious but paralysed.

⚠️ Key Clinical Syndromes

• Ischaemic stroke: MCA infarcts are the most common; emboli often originate from the left atrium in AF.
• Haemorrhagic stroke: Subarachnoid haemorrhage often stems from berry aneurysm rupture (e.g., at the anterior communicating artery).
• Watershed infarcts: Occur in low-flow states between ACA-MCA and MCA-PCA territories.
• Clinical Relevance: Watershed infarcts can mimic bilateral cortical symptoms in hypotensive patients—often presenting with "man-in-a-barrel" syndrome (arm/leg weakness sparing the face).

❓ Clinical Case Quiz: Can You Localise the Stroke?

A 72-year-old patient presents with:

Right arm and face weakness

Difficulty understanding speech

No visual field deficits

Which artery is most likely affected?

A) ACA

B) MCA

C) PCA

D) Basilar artery

💡 Drop your answers below!

Which hemisphere, which lobe, and what vascular territory do these symptoms point to?

💬 Comments

What clinical neuro cases have you found the most challenging so far? 👇

#MedSchool #Neuroanatomy #StrokeSyndromes #ClinicalReasoning