Makindo Medical Notes

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🚨 Acute Hydrocephalus is a neurological and neurosurgical emergency requiring rapid recognition and intervention.

🔎 Aetiology

• Normal CSF volume ≈ 200 mL, produced mainly by the choroid plexus (~500 mL/day; ~20 mL/hr).
• CSF pathway: Lateral ventricles → Third ventricle → Fourth ventricle → Subarachnoid space via foramina of Luschka & Magendie.
• Absorbed via arachnoid granulations into venous sinuses.
• Hydrocephalus: Excess CSF accumulation → ventricular dilation → brain compression.
• Incidence: 1–2 per 1,000 live births.
• Types:
  • Communicating hydrocephalus: Blockage beyond ventricles (e.g., SAH, meningitis, carcinomatous meningitis).
  • Obstructive hydrocephalus: Blockage within CSF pathway (e.g., colloid cyst, aqueduct stenosis, tumours, Chiari malformations, Dandy-Walker).

🧠 Diagram of Ventricles

👶 Clinical Features in Infants

• Rapid head enlargement (due to open fontanelles).
• “Sun-setting eyes” 👀 (limited upward gaze due to tectal pressure).
• Irritability, poor head control, thin shiny scalp, tense fontanelle.
• Delayed milestones, breathing difficulty, cognitive impairment.

👩‍🦳 Clinical Features in Adults

• Severe headache, nausea, vomiting, blurred vision (papilloedema).
• Gait disturbance, truncal ataxia, UMN signs.
• Pituitary dysfunction (if suprasellar pressure).
• False-localising VI nerve palsy, impaired upward gaze (3rd ventricle enlargement).
• In severe cases: coma, pupillary changes, Cheyne-Stokes breathing.

🧪 Investigations

• CT/MRI: Dilated ventricles, mass lesion, obstructive vs communicating pattern.
• Communicating hydrocephalus → symmetrical ventricular dilation.

📸 Classical Imaging Signs

• Expansion of temporal horns.
• Convex third ventricular walls.
• Rounded frontal horns.
• Effacement of sulci.
• Ventricular enlargement out of proportion to cortical sulcal widening.

⚡ Management

• Emergency referral to neurosurgery.
• Surgical options:
  • Ventriculoperitoneal (VP) shunt: Most common. Diverts CSF to peritoneal cavity or pleural space.
  • External Ventricular Drain (EVD): Temporary drainage in acute cases.
  • Endoscopic Third Ventriculostomy (ETV): Alternative in obstructive hydrocephalus.
• Medications (bridging only): Acetazolamide, furosemide to reduce CSF production.
• Complications: Infection (ventriculitis, shunt colonisation), shunt obstruction, subdural haematoma, shunt fracture/disconnection.

🖼️ Imaging Examples