Canadian UnRuptured aneurysm Endovascular vs. Surgery


The best management for patients with unruptured intracranial aneurysms (UIAs) is currently uncertain.  Two treatments are commonly performed for this condition.  Surgical clipping, for years considered the gold standard, has recently been challenged by the emergence of endovascular treatment (EVT), a minimally invasive alternative.  Surgical clipping, when successful, usually results in definitive aneurysm exclusion (re-treatment rates as low as 1.5%), with attendant mortality and morbidity estimated at 7-10%.  In contrast, proponents of EVT claim lower treatment-related risks of mortality and morbidity (3-4%), at the cost of lower efficacy (20-40% risk of aneurysm recurrence, with 11.4% requiring re-treatment despite short periods of follow-up).  Although the hemorrhage rate from recurrent EVT-treated aneurysms is low (estimated at 0.3-1.1% per year, this is not clearly different from the natural history of an unruptured aneurysm (assuming 0.9-1.2%/yr).  The two treatments have never been compared in a randomized trial.


The CURES trial


The purpose of CURES is:

·         To compare the treatment efficacy of surgical clipping and endovascular coiling for unruptured intracranial aneurysms.

·         To compare morbidity and mortality related to a surgical or endovascular treatment strategy at one year within the context of an RCT.


CURES is a pragmatic RCT comparing anatomical and clinical outcome results.  For Phase I, 260 patients will be enrolled.  The primary hypothesis is:  surgical clipping of intradural, saccular, unruptured intracranial aneurysms is superior to endovascular management in terms of a lesser number of patients experiencing treatment failure, defined as having occurred when either: the intended initial modality (surgical or endovascular) fails to occlude the aneurysm, a “major” (saccular) angiographic aneurysm recurrence is found, or an intracranial hemorrhagic event occurs during the 1-year follow-up period.

Data on morbidity and mortality from Phase I will be applied to the larger clinical outcome portion of the trial (Phase II), which is likely to require at least 1000 patients.  Formulation of specific hypotheses for Phase II await the morbidity and mortality data from Phase I.


Contact info:


The CURES trial is conducted by Dr. Jean Raymond from University of Montreal, CHUM Notre-Dame hospital, Dr. Max Findlay and Dr. Tim Darsaut from the University of Alberta Mackenzie Health Science Centre .  If you are interested in joining the trial, please contact the Suzanne Nolet ( or Brenda Poworoznik ( Identifier:  NCT01139892 / CURES is funded by a grant from the Canadian Institutes of Health Research CIHR (MOP-119554)


Guylaine Gevry,
Dec 2, 2015, 11:23 AM
Guylaine Gevry,
Jan 26, 2016, 8:02 AM
Guylaine Gevry,
Dec 2, 2015, 11:22 AM