Patient management after flow diversion for unruptured intracranial aneurysms: A literature review and DELPHI consensus
Authors
Alexander Stebner, Department of Neuroradiology, University Hospital of Basel, Basel, Switzerland.
Marie-Sophie Schüngel, Department of Neuroradiology, University Hospital in Halle, Halle, Germany.
Salome Lou Bosshart, Department of Clinical Neurosciences, University of Calgary, Calgary, Canada.
Satoru Fujiwara, Department of Neurology, Kobe City Nishi-Kobe Medical Center, Kobe, Japan.
Genevieve Milot, Department of Surgery, Université Laval, Québec, Canada.
David Volders, Department of Radiology, University of Toronto, Toronto, Canada.
Kazutaka Uchida, Department of Neurosurgery, Hyogo Medical University, Nishinomiya, Japan.
Christine Hawkes, Division of Neurology, Sunnybrook Health Science Centre, Toronto, Canada.
Petra Cimflova, Department of Diagnostic and Interventional Neuroradiology, University Hospital of Bern, Bern, Switzerland.
Manu Moreu, Radiology department, Hospital Clínico San Carlos, Madrid, Spain.
Isabel Fragata, Department of Neuroradiology, ULS São José, Lisbon, Portugal.
Alexandra Paul, Department of Neurosurgery, Albany Medical Center Hospital, Albany, United States.
Umberto Pensato, Department of Neurology, IRCCS Humanitas Research Hospital, Rozzano, Italy.
Christian Ulfert, Department of Neuroradiologie, University Hospital Heidelberg, Heidelberg, Germany.
Donald Frei, Colorado Neurological Institute, Denver, United States.
Pervinder Bhogal, Department of Neuroradiology, Royal London Hospital, London, United Kingdom.
Joanna Schaafsma, Department of Medical Imaging, University Health Network, Toronto, Canada.
Sandor Nardai, Center of Neurosurgery and Neurointervention, Semmelweis University, Budapest, Hungary.
Syed Zaidi, Department of Neurology,, University of Toledo, Toledo, United States.
Mohammed Almekhlafi, Department of Clinical Neurosciences, University of Calgary, Calgary, Canada.
Shahid Nimjee, The Ohio State University Wexner Medical Center, Columbus, United States.
Pascal Mosimann, Department of Radiology, University of Toronto, Toronto, Canada.
James Kennedy, John Radcliffe Hospital, Oxford, United Kingdom.
Jeremy Rempel, Department of Radiology, University of Alberta, Edmonton, Canada.
Violoza Inoa, Department of Neurology, University of Tennessee Health Science Center, Memphis, United States.
Shinichi Yoshimura, Department of Neurosurgery, Hyogo Medical University, Nishinomiya, Japan.
Marc Ribo, Department of Neurology, Vall d'Hebron Hospital Universitari, Barcelona, Spain.
Demetrius Lopes, Advocate Health - MidwestFollow
John Wong, Department of Clinical Neurosciences, University of Calgary, Calgary, Canada.
et al
Recommended Citation
Stebner A, Schüngel MS, Bosshart SL, et al. Patient Management After Flow Diversion for Unruptured Intracranial Aneurysms: a Literature Review and DELPHI Consensus. Clin Neuroradiol. Published online December 19, 2025. doi:10.1007/s00062-025-01600-w
Abstract
Background: Unruptured intracranial aneurysms are a common and can have devastating outcomes if ruptured. Flow diversion has expanded treatment options, especially for wide-necked and blister aneurysms. Yet, optimal follow-up retreatment strategies in case of treatment failure remain unclear. A DELPHI consensus was initiated to understand current practice in aneurysm management after flow diverter treatment.
Methods: This DELPHI consensus was conducted during the 5 T Think Tank, following a scoping literature review. Experts discussed the results, responded to iterative questionnaires, which started with four open-ended questions, and concluded with ten closed-ended questions.
Results: Of the 40 attendees, 24 participants (60%) identified as experts in flow diversion and participated in the DELPHI process, which involved a literature search and three DELPHI rounds. Consensus was reached on performing the first assessment of the flow diverter during the procedure using cone-beam CT (77.8%), and on timing of the first follow up (at 6 months, 70.8%). For follow-up timing, an annual (57%) or semi-annual (43%) schedule was favored. No preference emerged for the follow-up imaging modality, with slight preferences for MRA (29%), followed by DSA (25%), DSA + MRA (21%), CTA (17%), and DSA + CTA (8%). Aneurysm growth (> 2 mm) was identified as a key criterion for retreatment. It was thought that combining clinical and angiographic metrics should be a key research priority, as it could potentially improve retreatment decision making compared to a purely angiographic outcome.
Conclusion: This DELPHI consensus highlights the complexity of decision-making for unruptured intracranial aneurysms. Despite these challenges, there was consensus among international experts on follow-up timing and decision drivers for retreatment.
Affiliations
Advocate Illinois Masonic Medical Center