Figure S1: Angle correction and optimization of Doppler settings to avoid ‘blooming’ and ‘aliasing’ artefacts.

Figure S2: Adaptation of pulse repetition frequency for optimal image quality.

Figure S3: Perfusion indices and vascular reactivity.

Figure S4: Major cerebral arteries and the circle of Willis.

Figure S5: Cerebral sinovenous system.

Figure S6: Small vessels with low velocity are depicted with a linear high-frequency probe.

Figure S7: Stenosis and flow velocity change in the great cerebral vein.

Figure S8: Arterial ischaemic stroke: absence of flow, luxury perfusion, or normal anatomic Doppler signal.

Figure S9: Thalamic arterial stroke types.

Figure S10: Transverse sinus thrombosis.

Figure S11: Visualization of Willis' cords; important to distinguish from thrombus.

Figure S12: Normal and abnormal flow patterns in circle of Willis after treatment with extracorporeal membrane oxygenation.

Figure S13: Sequence from carotid injury to medial striate perforator stroke to germinal matrix haemorrhage to venous infarction in an infant born preterm.

Figure S14: Dissection of the aorta with reversed flow in both carotid arteries.

Figure S15: Reduced arterial flow in cortex adjacent to germinal matrix haemorrhage with medullary venous infarction: spasm?

Figure S16: Flow pattern in infants with clinically relevant patent ductus arteriosus.

Figure S17: Flow patterns after birth asphyxia; poor correlation with lesion pattern.

Figure S18: Arteriovenous malformation proximal to the vein of Galen, dilated inferior sagittal sinus.

Figure S19: Infratentorial arteriovenous malformation with arterial fistula from the posterior inferior cerebellar artery, secondary dilatation of vein of Galen, and straight sinus.

Figure S20: Cavernoma and angioma.

Figure S21: Arterial aneurysm.

Figure S22: Sturge–Weber syndrome.

Figure S23: Plexus hyperplasia.