Hydrocephalus and Cerebrospinal Fluid Diversion — WACS Viva & Clinical Scenarios (Paediatric Neurosurgery and Congenital Anomalies)

Exam-style hydrocephalus and cerebrospinal fluid diversion viva scenarios with examiner probes and model answers for Neurosurgery candidates.

Scenarios covered

• SCENARIO 1: A 4-month-old infant presents with progressive macrocephaly, crossing head circumference percentiles, splayed cranial sutures, a tense non-pulsatile anterior fontanelle, and the setting-sun sign following neonatal Gram-negative meningitis. Discuss the diagnostic evaluation, calculate the Endoscopic Third Ventriculostomy (ETV) Success Score, and justify your choice between ETV with Choroid Plexus Cauterisation (ETV/CPC) and Ventriculoperitoneal (VP) Shunt placement in a West African clinical setting.
• SCENARIO 2: Describe the anatomical landmarks, surface projection (Kocher's point), trajectory, and endoscopic visual anatomy of the lateral and third ventricles required to safely perform an Endoscopic Third Ventriculostomy. Detail the critical vascular and neural relationships of the third ventricular floor and the technical precautions to avoid basilar artery injury.
• SCENARIO 3: A 5-year-old child with a VP shunt placed in infancy presents with acute lethargy, recurrent projectile vomiting, bradycardia, and unilateral sixth cranial nerve palsy. Outline your systematic algorithm for evaluating acute shunt malfunction, interpreting radiological shunt series and cranial computed tomography (CT), and executing emergency shunt revision versus temporising external drainage.
• SCENARIO 4: Detail the physiology of cerebrospinal fluid (CSF) secretion, circulation, and resorption pathways. Contrast the biomechanical compliance curves and the Monro-Kellie doctrine between infants with patent fontanelles and older children with closed cranial sutures.
• SCENARIO 5: Outline the pathophysiology, microbiological profile, clinical presentation, and definitive multi-stage management of an infected ventriculoperitoneal shunt presenting with hardware exposure and peritonitis.