title: Hydrogel versus Bare Platinum Coils in Patients with Large or Recurrent Aneurysms Prone to Recurrence after Endovascular Treatment: A Randomized Controlled Trial.
abstract: Some patients are at high risk of aneurysm recurrence after endovascular treatment: patients with large aneurysms (Patients Prone to Recurrence After Endovascular Treatment PRET-1) or with aneurysms that have previously recurred after coiling (PRET-2). We aimed to establish whether the use of hydrogel coils improved efficacy outcomes compared with bare platinum coils.
  
  
  
  PRET was an investigator-led, pragmatic, multicenter, parallel, randomized (1:1) trial. Randomized allocation was performed separately for patients in PRET-1 and PRET-2, by using a Web-based platform ensuring concealed allocation. The primary outcome was a composite of a residual/recurrent aneurysm, adjudicated by a blinded core laboratory, or retreatment, intracranial bleeding, or mass effect during the 18-month follow-up. Secondary outcomes included adverse events, mortality, and morbidity (mRS > 2). The hypothesis was that hydrogel would decrease the primary outcome from 50% to 30% at 18 months, necessitating 125 patients per group (500 for PRET-1 and PRET-2).
  
  
  
  The trial was stopped once 250 patients in PRET-1 and 197 in PRET-2 had been recruited because of slow accrual. A poor primary outcome occurred in 44.4% (95% CI, 35.5%-53.2%) of those in PRET-1 allocated to platinum compared with 52.5% (95% CI, 43.4%-61.6%) of patients allocated to hydrogel (OR, 1.387; 95% CI, 0.838-2.295;P= .20) and in 49.0% (95% CI, 38.8%-59.1%) in PRET-2 allocated to platinum compared with 42.1% (95% CI, 32.0%-52.2%) allocated to hydrogel (OR, 0.959; 95% CI, 0.428-1.342;P= .34). Adverse events and morbidity were similar. There were 3.6% deaths (1.4% platinum, 5.9% hydrogel;P= .011).
  
  
  
  Coiling of large and recurrent aneurysms is safe but often poorly effective according to angiographic results. Hydrogel coiling was not shown to be better than platinum.
authors.affiliation: From the Departments of Radiology (J.R., A.W., F.G., D.R.) jean.raymond@umontreal.ca.
authors.forename: J
authors.identifier: 0000-0003-1978-4274
authors.initials: J
authors.lastname: Raymond
authors.affiliation: Laboratory of Interventional Neuroradiology (R.K.), Research Centre of the Centre Hospitalier de l'Université de Montreal, Quebec, Canada.
authors.forename: R
authors.identifier: 0000-0002-6129-3068
authors.initials: R
authors.lastname: Klink
authors.affiliation: Department of Mathematics and Statistics (M.C.), Université de Montréal, Montreal, Quebec, Canada.
authors.forename: M
authors.identifier: 0000-0002-2291-9566
authors.initials: M
authors.lastname: Chagnon
authors.affiliation: Department of Neurological Surgery (S.L.B.), Oregon Health and Science University, Portland, Oregon.
authors.forename: S L
authors.initials: SL
authors.lastname: Barnwell
authors.affiliation: Department of Radiology and Medical Imaging (A.J.E.), University of Virginia, Charlottesville, Virginia.
authors.forename: A J
authors.identifier: 0000-0002-2562-7462
authors.initials: AJ
authors.lastname: Evans
authors.affiliation: Department of Neurosurgery (J.M.), Mount Sinai Health System, New York, New York.
authors.forename: J
authors.identifier: 0000-0001-5489-2524
authors.initials: J
authors.lastname: Mocco
authors.affiliation: Department of Neurosurgery (B.H.H.), University of Florida, Gainesville, Florida.
authors.forename: B H
authors.identifier: 0000-0002-4997-4469
authors.initials: BH
authors.lastname: Hoh
authors.affiliation: Department of Neurosurgery (A.S.T., R.D.T.), Medical University of South Carolina, Charleston, South Carolina.
authors.forename: A S
authors.identifier: 0000-0001-8375-0410
authors.initials: AS
authors.lastname: Turk
authors.affiliation: Department of Neurosurgery (A.S.T., R.D.T.), Medical University of South Carolina, Charleston, South Carolina.
authors.forename: R D
authors.identifier: 0000-0002-4533-3648
authors.initials: RD
authors.lastname: Turner
authors.affiliation: Service de Neuroradiologie Diagnostique et Interventionnelle (H.D.), Centre Hospitalier Universitaire de Nantes, Nantes, France.
authors.forename: H
authors.identifier: 0000-0002-4665-1461
authors.initials: H
authors.lastname: Desal
authors.affiliation: Cerebrovascular Center (D.F.), Stony Brook University Medical Center, Stony Brook, New York.
authors.forename: D
authors.identifier: 0000-0002-2677-8780
authors.initials: D
authors.lastname: Fiorella
authors.affiliation: Département de Neuroradiologie Diagnostique et Interventionnelle (S.B.), Centre Hospitalier Universitaire de Nancy, Nancy, France.
authors.forename: S
authors.identifier: 0000-0001-9423-6660
authors.initials: S
authors.lastname: Bracard
authors.affiliation: From the Departments of Radiology (J.R., A.W., F.G., D.R.).
authors.forename: A
authors.identifier: 0000-0002-0281-6201
authors.initials: A
authors.lastname: Weill
authors.affiliation: From the Departments of Radiology (J.R., A.W., F.G., D.R.).
authors.forename: F
authors.identifier: 0000-0002-7866-0493
authors.initials: F
authors.lastname: Guilbert
authors.affiliation: Neurosciences (S.L.), Centre Hospitalier de l'Université de Montreal, Montreal, Quebec, Canada.
authors.forename: S
authors.identifier: 0000-0001-9762-5514
authors.initials: S
authors.lastname: Lanthier
authors.affiliation: Department of Medical Imaging (A.J.F.), University of Toronto, Toronto, Ontario, Canada.
authors.forename: A J
authors.identifier: 0000-0001-5465-5801
authors.initials: AJ
authors.lastname: Fox
authors.affiliation: Department of Surgery (T.E.D.), Division of Neurosurgery, University of Alberta Hospital, Edmonton, Alberta, Canada.
authors.forename: T E
authors.identifier: 0000-0003-4662-1550
authors.initials: TE
authors.lastname: Darsaut
authors.affiliation: Stroke Research Group (P.M.W.), Institute of Neuroscience, Newcastle Upon Tyne, UK.
authors.forename: P M
authors.identifier: 0000-0001-6007-6013
authors.initials: PM
authors.lastname: White
authors.affiliation: From the Departments of Radiology (J.R., A.W., F.G., D.R.).
authors.forename: D
authors.identifier: 0000-0002-6066-4453
authors.initials: D
authors.lastname: Roy
mesh_terms: D000328:Adult; D000368:Aged; D017542:Aneurysm, Ruptured / Q000601:surgery; D004621:Embolization, Therapeutic / Q000295:instrumentation* / Q000379:methods; D057510:Endovascular Procedures / Q000295:instrumentation* / Q000379:methods; D005260:Female; D006801:Humans; D020136:Hydrogel, Polyethylene Glycol Dimethacrylate / Q000627:therapeutic use*; D002532:Intracranial Aneurysm / Q000601:surgery*; D008297:Male; D008875:Middle Aged; D010984:Platinum; D012008:Recurrence; D019233:Retreatment; D016896:Treatment Outcome
chemical_list: D020136:Hydrogel, Polyethylene Glycol Dimethacrylate; D010984:Platinum