Cerebral Microbleeds with a Venous Connection on 3 Tesla Susceptibility-Weighted Imaging in Persons with Alzheimer’s Disease and Healthy Aging Controls

<b>Introduction</b>: It has been recently demonstrated that some cerebral microbleeds (CMBs) are connected to cerebral veins in patients with cerebral small vessel disease (CSVD) including cerebral amyloid angiopathy (CAA). We sought to demonstrate the presence of CMB at 3 Tesla using susceptibility-weighted imaging and speculated that it was more prevalent in persons with Alzheimer's disease (AD), another amyloid-related disease, than in healthy ageing controls. <b>Material and Methods</b>: We included persons from the publicly available OASIS3-database. Persons were included if they had a structural MRI including a susceptibility-weighted sequence (SWI) and relevant clinical data. Two raters assessed the presence and location of CMBs and CMBs with a venous connection (CMB_ven). <b>Results</b>: A total of 571 persons (AD, <i>n</i> = 140, healthy controls, <i>n</i> = 431) were included. In total, 367 CMBs were detected, encompassing 26/571 persons (4.5%) who had a total of 40/367 (10.9%) CMBs with a CMB_ven, though there was no difference between persons with AD and healthy controls (AD 6.6%, healthy controls 7.4%, <i>p</i> = 0.773). Persons with CMB_ven had a higher total CMB load, were more likely female, displayed an APOE ε2/2 genotype and had antithrombotic treatment more often. Logistic regression revealed a higher number of CMB (OR (95% CI) = 1.351 (1.161-1.688), <i>p</i> < 0.0014) and a lower MoCA score (OR (95% CI) = 0.862 (0.762-0.982), <i>p</i> = 0.018), indicating a statistically significant association with the presence of CMB_ven. <b>Discussion</b><i>:</i> CMB_ven are not an uncommon finding in persons with AD and healthy ageing controls. Our results highlight the potential venous contribution to CSVD. Histopathological studies will be needed to assess these further.