Usually, this collection has a traumatic etiology.
Recognized risk factors for development of CSDH are head injury, old age and using anticoagulant, but its underlying pathophysiological processes are still unclear. It is assumed that a complex local process of interrelated mechanisms including inflammation, neomembrane formation, angiogenesis and fibrinolysis could be related to its development and propagation.
Chronic subdural hematomas mainly occur amongst elderly people and usually develop after minor head injuries.
In younger patients, subdural collections may be related to hypertension, coagulopathies, vascular abnormalities, and substance abuse.
A retrospective review of 239 patients undergoing surgery for CSDH over a period of six years (2006-2011). The majority of patients (63%) in the non-trauma group were receiving anticoagulants and/or antiplatelet agent therapy prior to CSDH presentation, compared to 42% in the trauma group. 1).
Isolated SDH is a rare complication of DAVF. In this report, we presented a rare case of CSDH secondary to an intracranial DAVF. According to this case report and our literature review, the so-called benign type of DAVF without cortical venous drainage does not always warrant a benign process and might be complicated with SDH. Careful preoperative investigation is needed for relative young patients presenting with idiopathic or atypical SDH 2).