The optimal treatment of IAD is unknown. There are no randomised trials and only observational studies with relatively small sample sizes are available, thus providing a very low level of evidence. Patients with SAH IAD are usually treated by surgery or endovascular procedures because up to 40% of the patients experience re-bleeding within the first days after the event. Various surgical and endovascular treatment methods have been proposed for intracranial dissecting aneurysms. When patients are in poor clinical condition or treatment has an unacceptably high complication risk, it can be decided to withhold from surgical or endovascular treatment. In addition, Most non-SAH IAD patients have been treated medically, but the choice of antithrombotic therapy (anticoagulants or antiplatelet agents) has been evaluated neither in randomised trials nor in systematic reviews and meta-analyses of observational data. As a consequence, there is currently no consensus on optimal treatment of IAD.