C78 Dissecting posterior cerebral artery aneurysm presenting as neonatal sah: a case-based insight

<h3>Introduction</h3> Neonatal cerebral aneurysms are extremely rare and have different characteristics from those seen in adults. Dissecting aneurysms are the most common aneurysm subtype in children. In neonates, the vessel wall may be particularly vulnerable due to immature structural integrity. <h3>Case Description</h3> We present the case of a 16-day-old neonate who presented with seizures, fever and signs of increased intracranial pressure. Initial ultrasound was inconclusive, but follow-up imaging revealed progressive hydrocephalus. MRI and MRA revealed a dissecting fusiform aneurysm of the left posterior cerebral artery (PCA) with associated subarachnoid and intraventricular haemorrhage, which was successfully excluded from the circulation by endovascular coiling of the aneurysm base. Post-intervention, the patient developed cranial nerve III palsy and PCA territory infarction. We also review the literature on this condition and its management. <h3>Conclusions</h3> This case highlights the importance of including cerebral aneurysms in the differential diagnosis of neonatal intracranial haemorrhage and the importance of early vascular imaging in neonatal subarachnoid haemorrhage. Furthermore, our case demonstrates that endovascular coiling is a viable first-line treatment for dissecting aneurysms even in neonates. Long-term neurodevelopmental monitoring remains critical in this vulnerable population. <h3>Conflict of Interest</h3> No