Neonatal stroke and intracranial haemorrhage — formative SAQs

SAQ 1 — The term infant with focal seizures (20 marks, ~15 minutes)

A term infant (39 weeks, birthweight 3400 g) is born by emergency caesarean for failure to progress after an instrumental attempt. Apgar scores are 6, 8, and 9. At 30 hours of age the midwife notes rhythmic jerking of the right arm and right side of the face lasting two minutes. Between events the infant is alert but has a reduced grasp and asymmetry of tone favouring the left side. Blood glucose is 3.2 mmol/L. Cranial ultrasound on day 2 is reported as normal. ^[1]

Questions

1. What is the most likely diagnosis, and why does the normal cranial ultrasound not exclude it? (4 marks) ^[1]
2. Outline your immediate management priorities for this infant. (5 marks) ^[1]
3. Describe the definitive neuroimaging investigation and what it would show. (4 marks) ^{[1] [3]}
4. Discuss the prognosis and the follow-up pathway, citing the evidence for outcome prediction. (7 marks) ^{[3] [8]}

Model answer (must-hit)

1. The most likely diagnosis is perinatal arterial ischaemic stroke (PAIS), presenting with focal clonic seizures and asymmetric tone at 30 hours. A normal cranial ultrasound does not exclude PAIS because ultrasound is poor at visualising the cortical surface and may miss a focal cortical infarct; MRI with diffusion-weighted imaging is required. ^[1]
2. Immediate management: maintain airway and oxygenation; check and correct glucose (already 3.2 mmol/L — normal); secure IV access; give phenobarbital 20 mg/kg IV for the seizure; start continuous EEG if available; maintain normoxia, normoglycaemia, normotension, and normothermia; arrange MRI in parallel. ^[1]
3. MRI brain with diffusion-weighted imaging (DWI) is the definitive investigation. DWI would show restricted diffusion in an arterial territory — most commonly the left middle cerebral artery — confirming acute ischaemia. SWI excludes haemorrhage and MRV excludes cerebral sinovenous thrombosis. ^{[1] [3]}
4. Prognosis: the Baak 2023 systematic review establishes that infarct size, corticospinal tract involvement, and early neurological severity predict outcome. Approximately 30 to 60 percent of PAIS survivors develop hemiplegic cerebral palsy, with cognitive impairment and epilepsy in a subset. Follow-up: structured neurodevelopmental surveillance with early detection of CP and a rehabilitation pathway per the Australian clinical consensus guideline (Greenham 2021). ^{[3] [8]}