Although CT can de ne ICH location, it cannot reliably identify the underlying type of causal small vessel disease. MRI can identify biomarkers of small vessel disease, including cerebral microbleeds (CMBs), whose distribution can be used to diagnose CAA with high speci city in ICH cohorts.335 In a recent pooled analysis of observational studies, patients with ICH classi ed using CMBs as due to CAA had an approximately 7% annual recurrence risk, compared with about 1% for those not ful lling criteria for CAA.336 Since OACs increase the risk of ICH, some experts have recommended avoiding them in patients with ICH attributed to CAA. In survivors of ischemic stroke and TIA, CMBs are also associated with increased risk of ischemic stroke, although as the number of CMBs increases, the risk of future ICH increases more steeply than that of ischemic stroke.337 In ICH survivors, the number of CMBs is also associated with the risk of Balancing the Risks of Ischemic Stroke and Recurrent ICH: A decision analysis which modeled warfarin for AF in an ICH survivor suggested that in lobar ICH, avoiding warfarin increased quality-adjusted life years by 1.9, compared with 0.3 for deep ICH; the authors concluded that anticoagulation for AF should not be offered to patients with lobar ICH and only to survivors of deep ICH if the risk of ischemic events was high (> However, CMBs were not considered in this analysis. In contrast, recent real-world observational studies (including some very large registry datasets) from ICH survivors with AF suggest that anticoagulation might reduce mortality and ischemic complications, without an unacceptable increase in ICH. 