Table 1.

CAA-related abnormal imaging findings

Disease	Imaging findings	Recommended neuroimaging modality
ICH	Haematoma with distinctive cortical-subcortical distribution generally sparing the deep white matter and basal ganglia and brainstem	CT and MRI MRI; additional depiction of chronic haemosiderin depositions and MBs
MBs	Small round hypointense foci on MRI	MRI, especially susceptibility-weighted image
SAH	Supratentorial sulcal high attenuation/intensity, most frequently depicted around the precentral gyrus	CT and MRI MRI; additional depiction of MB and SS
SS	Hypointensity along the supratentorial cerebral sulcus on MRI	MRI, especially susceptibility-weighted image
CAA-related inflammation	Large confluent asymmetric abnormal attenuation/intensity mainly in the subcortical WM	CT and MRI MRI; additional evaluation of vasogenic oedema and other findings such as MB and SS
Leukoaraiosis	Low attenuation on CT and high intensity on FLAIR and T2W MRI mainly in the deep WM with sparing of the subcortical U fibres	CT and MRI MRI; depiction of leukoaraiosis clearer than CT
Microinfarction	Small ovoid or round high intensity of the subcortical and cortex on diffusion-weighted image	MRI, especially diffusion-weighted image

CAA cerebral amyloid angiopathy, CT computed tomography, FLAIR fluid-attenuated inversion recovery, ICH intracerebral haemorrhage, MRI magnetic resonance imaging, MB microbleed, SAH subarachnoid haemorrhage, SS superficial siderosis, T2W T2-weighted, WM white matter