Table 4 The modified Boston criteria for predicting the probability of Chronic Amyloid Angiopathy (CAA) as the underlying cause of ICH

Definite CAA

Full post-mortem examination demonstrating:

  Lobar, cortical, or cortico-subcortical hemorrhage

  Severe CAA with vasculopathy

  Absence of other diagnostic lesion

Probable CAA with supporting pathology

Clinical data and pathologic tissue (evacuated hematoma or cortical biopsy) demonstrating:

  Lobar, cortical or cortical-subcortical hemorrhage (including ICH and/or CMB)

  Some degree of CAA in specimen

  Absence of other diagnostic lesion

Probable CAA

Clinical data and MRI or CT demonstrating:

  Multiple hemorrhages (ICH, CMB) restricted to lobar, cortical, or cortico-subcortical regions (cerebellar hemorrhages allowed),

  OR

  Single lobar, cortical or cortical-subcortical hemorrhage and cSS (focal or disseminated)

  Age ≥ 55 years

  Absence of other causes of hemorrhages* or cSS

Possible CAA

Clinical data and MRI or CT demonstrating:

  Single, lobar, cortical, or cortico-subcortical ICH, CMB;

  OR

  Presence of cSS (focal or disseminated)

  Age ≥ 55 years

  Absence of other causes of hemorrhages* or cSS