Unruptured Aneurysms Italian Study (UAIS) - background and method.

Treatment of unruptured cerebral aneurysms still represents an unsettled question in neurosurgical and neuroradiological communities. Although nowadays the indication for treatment have become relatively clear, indeed uncertainity remains for what concerns the proper treatment modality (surgical or endovascular)in terms of both the risk and the mid and long-term efficacy of the two procedures. The "Unruptured Aneurysms Italian Study" is a cooperative prospective study which aims to delineate the "State of the Art" in a nation based population. It has been designed: 1) to depict the nationwide modality of treatment of Unruptured Aneurysms, 2) to assess in the most objective way the overall treatment-related mortality and morbidity as well as the surgical and endovascular risk in the respective patient populations (it is not a surgical versus endovascular study) and 3) to asses the efficacy of the different procedures in the mid and long term periods. The study started on June 2003 and to June 2006, 637 patients have been enrolled. The study will end when the 1000th patient is enrolled.