Imaging. Exemplary images of matching slice plains. All images represent 5 mm slices, with images in A, B and D being reconstructions of thinner source images. MR images are of reduced quality due to motion artefacts. A: Non-enhanced CT: Diffuse subarachnoid hyperattenuations mimicking SAH. B: CT-angiography: Sulcal and basal veins dilated and increased in number. C: MRI, FLAIR sequence: No findings of SAH. D: MRI, SWAN sequence: Markedly hypointense depiction of cerebral and subarachnoidal veins due to hypoxaemia.