Cerebellar Ischaemic Stroke

Related Subjects: |Acute Stroke Assessment (ROSIER&NIHSS) |Causes of Stroke

🧠 Introduction

Cerebellar ischaemic stroke occurs when blood flow to the cerebellum is interrupted, causing infarction. Although <5% of all strokes, they can be life-threatening due to posterior fossa crowding → brainstem compression & obstructive hydrocephalus. 🚨 Early recognition + treatment are vital.

📌 About

• ⏳ <5% of strokes, but risk of rapid deterioration.
• 🔬 MRI detects small (<2 cm) cerebellar infarcts often with benign prognosis.
• 💥 Even small oedema can dangerously ↑ ICP or compress the brainstem.
• 🧪 Swelling = cytotoxic + vasogenic oedema.

🩸 Blood Supply

• SCA (Superior Cerebellar Artery): superior cerebellum, midbrain, pons.
• AICA (Anterior Inferior Cerebellar Artery): anterior–inferior cerebellum + lateral pons; labyrinthine branch → inner ear.
• PICA (Posterior Inferior Cerebellar Artery): posterior–inferior cerebellum + lateral medulla.

🩻 Venous drainage → superior & inferior cerebellar veins → petrosal, transverse & straight sinuses.

⚠️ Aetiology

• 🫀 Large artery atherosclerosis (vertebrobasilar, artery-to-artery embolism).
• ❤️ Cardioembolism: AF, LV aneurysm, IE, post-MI.
• 🪢 Vertebral artery dissection (trauma, manipulation).
• 🩺 Procedural: e.g. post-cardiac catheterisation.
• 🧬 Others: PFO paradoxical embolus, thrombophilia, vasculitis.

🩺 Clinical Features

• 🎢 Vertigo/dizziness ± vomiting (sudden severe).
• 🤕 Occipital headache.
• 🚶 Ataxia: ipsilateral limb/gait ataxia.
• 👀 Nystagmus: horizontal or vertical.
• 🗣 Dysarthria/dysphagia: CN nuclei involvement.
• 👁 Diplopia.
• 😴 ↓ Consciousness → brainstem compression.
• 🔥 Horner’s syndrome: ptosis + miosis + anhidrosis.
• 🦶 Positive Babinski: CST involvement.
• 💔 Cardiac findings: AF, post-MI clues to embolic source.

🔑 Exam pearl: Vertigo + ataxia + dysarthria + nystagmus = think cerebellar stroke, not just vestibular disease.

🆚 Differentials

• 🦻 Labyrinthitis / Vestibular neuritis (peripheral vertigo).
• 🍺 Alcohol intoxication.
• 💊 Phenytoin / anticonvulsant toxicity.
• 🧬 Multiple sclerosis.
• 🎗 Posterior fossa tumour.

⚠️ Complications

• 💧 Hydrocephalus: 4th ventricle obstruction.
• 🧩 Brainstem compression: oedema + herniation risk.
• 😴 Coma/resp arrest: brainstem failure.
• 🫁 Aspiration pneumonia (swallowing dysfunction).
• 🦵 DVT/PE: immobility complications.

🔍 Investigations

• 🩸 Bloods: FBC, U&E, glucose, lipids, coagulation.
• 📉 ECG: AF, arrhythmias.
• 🫁 CXR: cardiac size, infection.
• 🖼 CT: excludes bleed; may show infarct late.
• 🧲 MRI DWI: sensitive for acute infarct.
• 🖼 CTA/MRA: vertebrobasilar occlusion, dissection.
• 🫀 Echo: embolic source.

⚕️ Management

• 🛌 Stabilisation: ABCs, ICU/HDU, close neuro obs.
• 💉 IV thrombolysis: if <4.5h, no contraindications.
• 🧑‍⚕️ Thrombectomy: selected posterior circulation occlusions.
• 💊 Antiplatelet: aspirin 300mg if not thrombolysed, after bleed excluded.
• 🧠 ICP management: head elevation, mannitol/hypertonic saline, neuro referral.
• 🔪 Neurosurgery: decompressive suboccipital craniectomy, EVD if hydrocephalus.
• 🤝 Supportive: DVT prophylaxis, swallow safety, physio/OT/speech rehab.
• 🛡 Secondary prevention: anticoagulate AF, statins, control BP, stop smoking.

📈 Prognosis

• 🌱 Small infarcts: often good recovery.
• ⚡ Large strokes: high mortality due to mass effect.
• 🔪 Early decompression: can save lives and improve outcomes.

📚 References

• Adams & Victor’s Principles of Neurology – Cerebellar Stroke.
• AHA/ASA Guidelines for Acute Ischaemic Stroke.
• Edlow JA, Newman-Toker DE. Acute dizziness diagnostic approach. J Emerg Med. 2008.
• Voetsch B et al. Basilar artery occlusive disease. Arch Neurol. 2004.