The CANHOPE study falls within the scope of research on patients' experiences and the improvement of their management through interventions meeting their needs. The study protocol assesses a support program for patients with untreated intracranial aneurysms (ICAs), for whom several sources of data converge in describing inadequacies in patients' care pathway and a deleterious impact on their health. The initial questioning is based on the practice of caregivers, who are witnesses of patients' feelings during ICA follow-up and are sometimes unable to support them due to a lack of knowledge about the impact of the disease and an organization that does not provide any space dedicated to their support. The study topic described below explains the medical context of ICA, and the data available in the literature on the impact of this condition on patients' lives. These data are complemented by the results of a qualitative study recently conducted in Nantes University Hospital in 10 subjects who participated in two focus groups. The discussions have revealed many areas of tension related to the management of uncertainty: questions arise after the consultation; there should be an ALLO INFO ANEURYSM number; if it ruptures, it's over, that's what I've understood; I fall asleep every night thinking it might be the last time. The need for specific support, particularly during the first year, appears to be obvious. Based on these experiences, it has been hypothesized that an allied health follow-up of patients managed by simple monitoring, focused on the management of uncertainty, during the first year following the announcement, could reduce anxiety and improve patients' quality of life. Inspired by participants' experiences and guided by the uncertainty in illness theory, the study is focused on proposing an allied health management organized around items known to sustain patients' hope. The aim of the CANHOPE study is therefore to assess the CANHOPE program, in order to provide clinicians and decision-makers with the data they need to support the implementation of this program in referral centers for ICA follow-up. This study will be conducted in two parallel parts: 1/ a multicenter, cluster, randomized, controlled trial and 2/ a comprehensive qualitative study.