The Lancet Neurology (08/01/22) Vol. 21, No. 8, P. 714, DOI: 10.1016/S1474-4422(22)00208-3
Charidimou, Andreas; Boulouis, Gregoire; Frosch, Matthew P.; et al.
An international collaborative study sought to update the Boston diagnostic criteria for the full range of cerebral amyloid angiopathy (CAA) presentations. The criteria had not been updated since 2010. The authors conducted a retrospective analysis of clinical, radiological, and histopathological data available to sites participating in the International CAA Association. In all, 10 academic medical centers in North America and Europe identified patients aged 50 years and older with clinical presentations possibly related to CAA, such as spontaneous intracerebral hemorrhage, cognitive impairment, and transient focal neurological episodes; available brain MRI, and histopathological assessment for the diagnosis of CAA. For hemorrhagic and non-hemorrhagic CAA markers, MRI scans were centrally rated at Massachusetts General Hospital (MGH) in Boston, while brain tissue samples were rated by neuropathologists from contributing sites. There were 218 patients eligible for inclusion at MGH and 123 from other centers. Based on a prespecified derivation cohort consisting of 159 Boston cases from 1994-2012, the researchers derived provisional criteria for probable CAA requiring the presence of at least two strictly lobar hemorrhagic lesions or at least one strictly lobar hemorrhagic lesion and at least one white matter characteristic. Overall, the sensitivity and specificity of these criteria were 74.8% and 84.6% in the derivation cohort, compared with 92.5% and 89.5% in the temporal validation cohort (Boston cases 2012-2018, n=59), 80.2% and 81.5% in the geographical validation cohort (non-Boston cases 2004-2018, n=123), and 74.5% and 95.0% for patients who had autopsy as the diagnostic standard. The area under the receiver operating characteristic curve (AUC) for the four groups was 0.797, 0.910, 0.808, and 0.848, respectively. The updated criteria for probable CAA had superior accuracy to the existing Boston criteria for all individuals who had autopsy as the diagnostic standard. "The Boston criteria v2.0 incorporate emerging MRI markers of CAA to enhance sensitivity without compromising their specificity in our cohorts of patients aged 50 years and older presenting with spontaneous intracerebral hemorrhage, cognitive impairment, or transient focal neurological episodes," the researchers conclude.