Are Topographical Patterns of Microbleeds Enough to Determine a Difference Between Amyloid and Hypertensive Angiopathy?
Alejandro Rodríguez-Vázquez, MD
Jung YH, Jang H, Park SB, Choe YS, Park Y, Kang SH, Lee JM, Kim JS, Kim J, Kim JP, et al. Strictly Lobar Microbleeds Reflect Amyloid Angiopathy Regardless of Cerebral and Cerebellar Compartments. Stroke. 2020;51:3600–3607.
Nowadays, Boston criteria are pillars for the diagnosis of cerebral amyloid angiopathy (CAA). According to those criteria, CAA diagnosis is excluded due to the presence of deep microbleeds independent of other neuroimaging findings and in absence of pathology. However, Thal et al. proposed that CAA pathology extends sequentially from cortical to cerebellar and finally basal ganglia and brainstem vessels. Therefore, deep microbleeds added to lobar both cerebral and cerebellar ones do not exclude CAA but are related to an advanced stage of the disease.
In this study, the authors tried to determine if the topographical pattern of microbleeds could help to establish the underlying pathophysiology comparing amyloid-β burden and cerebral small vessel disease markers according to the anatomic distribution of microbleeds. From 2333 patients who visited the authors’ memory clinic, they included 71 with suspected CAA markers on MRI neuroimaging, and they categorized them in 4 groups based on the distribution of microbleeds: strictly lobar (n=33); strictly lobar cerebral and strictly lobar cerebellar (n=13); lobar, cerebellar both lobar and dentate and deep (n=17); and lobar and deep (n=7). Brainstem microbleeds were categorized as deep. In addition, they performed an amyloid-β PET and a complete cognitive assessment. The prevalence of hypertension was slightly higher on the lobar and deep group than in the strictly lobar, but the rest of classic cardiovascular risk factors and dementia did not significantly differ between groups.