Paediatric intra-axial posterior fossa tumours: pictorial review
- 1Department of Imaging and Interventional Radiology, The Chinese University of Hong Kong, Prince of Wales Hospital, Shatin, New Territories, Hong Kong
- 2Department of Paediatrics, The Chinese University of Hong Kong, Prince of Wales Hospital, Shatin, New Territories, Hong Kong
- Correspondence to Professor Winnie Chiu-Wing Chu, Department of Imaging and Interventional Radiology, The Chinese University of Hong Kong, Prince of Wales Hospital, Ngan Shing St, Shatin, New Territories, Hong Kong;
- Received 4 April 2011
- Accepted 18 August 2012
- Published Online First 12 September 2012
Paediatric brain tumours commonly arise in the posterior cranial fossa. Early diagnosis is often challenging due to initial non-specific clinical symptoms, especially in very young children. The typical MR features of tumours in this region including medulloblastoma, ependymoma, juvenile pilocytic subtype of cerebellar astrocytoma, brain stem glioma and atypical teratoid–rhabdoid tumour are illustrated. Diffusion-weighted imaging and apparent diffusion coefficient values combined with signal characteristics on conventional MR sequences can usually differentiate low-grade from high-grade tumours. Prompt diagnosis is crucial as total surgical resection, which is only possible in localised disease, improves prognosis. A practical MR flow chart is introduced for differentiating different types of posterior cranial fossa tumours, which might be useful in clinical practice.