As the Boston criteria for cerebral amyloid angiopathy were last updated in 2010 (v1.5), a new multicentre study based on neuropathological and neuroimaging findings was performed in order to enhance the criteria.
The core novelty of the 2.0 Boston criteria is the inclusion of white matter characteristics: Severely enlarged perivascular spaces and/or white matter hyperintensities in a specific, so-called multispot pattern. Severe perivascular spaces are defined as more than 20 visible perivascular spaces in the centrum semiovale of one hemisphere on axial T2-weighted images. The multispot white matter hyperintensity pattern is defined as more than ten small circular or ovoid hyperintense FLAIR lesions in the subcortical white matter of both hemispheres.
In the new criteria, probable CAA is now defined as either the presence of two strictly lobar haemorrhagic lesions (intracerebral haemorrhage, microbleeds, or cortical superficial siderosis), or the presence of one strictly lobar haemorrhagic lesion plus at least one white matter characteristic (as defined above). These criteria apply to patients ≥50 years who present with intracerebral haemorrhage, transient focal neurological episodes or cognitive impairment (and in absence of any deep haemorrhagic lesions and other causes of haemorrhagic lesions).
Possible CAA is defined as either one strictly lobar haemorrhagic lesion or at least one white matter characteristic as defined above.
These new criteria have improved accuracy and provide a valuable basis for the clinical diagnosis of CAA.
- New diagnostic criteria for cerebral amyloid angiopathy (CAA) have been proposed
- The novelty is the inclusion of specific white matter characteristics in addition to lobar haemorrhagic lesions
- Probable CAA is defined as two strictly lobar haemorrhagic lesions or one plus white matter characteristics
Charidimou A, Boulouis G, Frosch MP, et al. The Boston criteria version 2.0 for cerebral amyloid angiopathy: a multicentre, retrospective, MRI-neuropathology diagnostic accuracy study. Lancet Neurol. 2022;21(8):714-725. doi:10.1016/S1474-4422(22)00208-3; https://pubmed.ncbi.nlm.nih.gov/35841910/