Chronic subdural hematoma (cSDH) is one of the most common neurosurgicalconditions. Its prevalence is significantly higher among patients older than 65,and therefore 41% of the patients are treated with platelet aggregationinhibitors or oral anticoagulants. Antiplatelet therapy in patients with cSDH presents a significant neurosurgical challenge. Studies investigating the effect of acetylsalicylic acid (ASA) in cranial neurosurgery in generel and cSDH in particular are sparse. Given the lack of guidelines regarding perioperative management of antiplatelet therapy, it is difficult to balance thepatient’s increased cardiovascular risk and risk for recurrent cSDH. The aim of ourrandomized, placebo controlled, double blinded study is to compare the peri-­ andpostoperative bleeding and cardiovascular complication rates of patients undergoingburr-­hole trepanation for cSDH with and without discontinuation of low-­dose ASA. The Primary outcome is the rate of recurrence after burr-­hole trepanation for cSDH under low-­dose aspirin treatment compared to placebo treatment. Secondary outcomes are the rate of thrombotic events,perioperative blood loss, postoperative anemia, intra-­ and postoperative bloodtransfusion rates, and clinical outcome (mRS, GOS, Markwalder score). With this study we aim to elucidate an issue of growing clinical relevance, clinicians are dailyconfronted with.