Document resource
Amyloid-related imaging abnormalities (ARIA) represent a spectrum of MRI-detectable complications linked to anti-amyloid monoclonal antibody therapies for Alzheimer’s disease (AD). 1 2 The pathophysiology arises from the interplay between amyloid-β (Aβ) clearance and vascular inflammation (figure 1).1 These antibodies mediate parenchymal amyloid clearance with coincident destabilisation of cerebrovascular integrity, particularly in patients with pre-existing cerebral amyloid angiopathy (CAA). This process mobilises Aβ fragments that overwhelm perivascular drainage, triggering an inflammatory cascade and blood-brain barrier (BBB) disruption. The resultant manifestations are vasogenic oedema/sulcal effusion (ARIA-E) and microhaemorrhages/superficial siderosis (ARIA-H). Their frequent co-occurrence underscores a shared mechanism of Aβ-mediated vascular injury.3