Clinical and radiologic distinctions between familial cavernous malformation syndrome and cerebral amyloid angiopathy

Familial cerebral cavernous malformation syndrome (FCCM) is characterized by multiple hemorrhagic lesions and is sometimes mistaken for cerebral amyloid angiopathy (CAA).

We compared clinical and radiologic characteristics in patients with definite (N = 32) and presumed FCCM (n = 76) to patients with definite (N = 29) and probable CAA (N = 21).

Patients with CAA were older (78.6 years CAA vs. 43.4 FCCM; p < 0.0001), had cognitive complaints (66.0% CAA vs. 8.3% FCCM; p < 0.0001), and less likely to have a family history (4.0% CAA vs. 50.9% FCCM; p < 0.0001). FCCM patients were more likely to have at least 1 Zabramski type 2 lesion (0 CAA vs. 79.6% FCCM; p < 0.0001). Presence of any subcortical white matter hemorrhagic lesion (23.0% CAA vs. 99.1% FCCM; p < 0.0001), a lesion in either the basal ganglia, internal capsule or cerebellum (28.0% CAA vs 79.6% FCCM; p < 0.0001) and a subcortical white matter to cortical ribbon distribution of hemorrhagic lesions ≥ 1.0 was predictive of FCCM (6.0% CAA vs 83.9% FCCM; p < 0.0001). CAA patients more commonly had white matter disease, sulcal subarachnoid hemorrhage, and severely enlarged perivascular spaces in the centrum. However, none of the latter features were unique to CAA. FCCM patients meeting Boston 2.0 criteria for CAA (n = 14) had additional factors that helped distinguish them from CAA.

Patients with FCCM can be reliably distinguished from CAA by accurately applying the Boston 2.0 criteria, assessing hemorrhagic lesion distribution and types, and assessing for clinical features unique to FCCM. FCCM criteria are proposed. The frequent finding of leukoaraiosis and enlarged perivascular spaces in the centrum semiovale in FCCM patients deserves further investigation.