Paediatric cerebrovascular disease: Neuroradiological diagnosis

The low incidence (2.6 cases in 100,000) of cerebrovascular disease in paediatric patients compared with the adult population makes it a diagnostic challenge. Etiological factors have changed over time: whereas in the past bacterial meningitis was the most frequent cause, heart disease, haematological disorders, vasculopathy and viral infections have now become the most common. Haemorrhagic stroke is most frequently due to arteriovenous malformations (AVMs), cavernous angioma, haematological disorders and intracranial aneurysms. Traumatic or fibrodyplastic arterial thrombosis is extremely rare. Venous thrombosis most commonly affects the upper sagittal sinus. In two thirds of cases the cause of stroke remains unknown. For years, symptoms of acute CNS deficits have been studied with computed tomography (CT), especially to rule out haemorrhage. To avoid exposing paediatric patients to ionizing radiation, magnetic resonance imaging (MRI), more sensitive and specific for the identification of acute ischaemic stroke, is currently the first-line diagnostic technique. In particular, diffusion-weighted sequences are capable of early identification of ischaemic areas. Association with perfusion techniques will define the areas at high risk of further damage and to attempt to estimate the final volume of the lesion. MR spectroscopy contributes to the characterization of ischaemic lesions. MR angiography (MRA) has proved to be a non-invasive technique with the same diagnostic effectiveness as conventional angiography for dissections, transient cerebral arteriopathy and moyamoya. The cervical arteries are studied using contrast-enhanced sequences. Conventional angiography remains the technique of choice for the study of small vessels disease and AVMs.