title: Follow-up of intracranial aneurysms treated by flow diverter: comparison of three-dimensional time-of-flight MR angiography (3D-TOF-MRA) and contrast-enhanced MR angiography (CE-MRA) sequences with digital subtraction angiography as the gold standard.
abstract: OBJECTIVE
  Follow-up of intracranial aneurysms treated by flow diverter with MRI is complicated by imaging artifacts produced by these devices. This study compares the diagnostic accuracy of three-dimensional time-of-flight MR angiography (3D-TOF-MRA) and contrast-enhanced MRA (CE-MRA) at 3 T for the evaluation of aneurysm occlusion and parent artery patency after flow diversion treatment, with digital subtraction angiography (DSA) as the gold standard.
  
  
  METHODS
  Patients treated with flow diverters between January 2009 and January 2013 followed by MRA at 3 T (3D-TOF-MRA and CE-MRA) and DSA within a 48 h period were included in a prospective single-center study. Aneurysm occlusion was assessed with full and simplified Montreal scales and parent artery patency with three-grade and two-grade scales.
  
  
  RESULTS
  Twenty-two patients harboring 23 treated aneurysms were included. Interobserver agreement using simplified scales for occlusion (Montreal) and parent artery patency were higher for DSA (0.88 and 0.61) and CE-MRA (0.74 and 0.55) than for 3D-TOF-MRA (0.51 and 0.02). Intermodality agreement was higher for CE-MRA (0.88 and 0.32) than for 3D-TOF-MRA (0.59 and 0.11). CE-MRA yielded better accuracy than 3D-TOF-MRA for aneurysm remnant detection (sensitivity 83% vs 50%; specificity 100% vs 100%) and for the status of the parent artery (specificity 63% vs 32%; sensitivity 100% vs 100%).
  
  
  CONCLUSIONS
  At 3 T, CE-MRA is superior to 3D-TOF-MRA for the evaluation of aneurysm occlusion and parent artery patency after flow diversion treatment. However, intraluminal evaluation remains difficult with MRA regardless of the sequence used.
authors.affiliation: Department of radiology, Hôpital Maison Blanche, Université de Champagne-Ardenne, Reims, France.
authors.forename: Jonathan
authors.initials: J
authors.lastname: Attali
authors.affiliation: Department of radiology, Hôpital Maison Blanche, Université de Champagne-Ardenne, Reims, France.
authors.forename: Azzedine
authors.initials: A
authors.lastname: Benaissa
authors.affiliation: Department of radiology, Hôpital Maison Blanche, Université de Champagne-Ardenne, Reims, France.
authors.forename: Sébastien
authors.initials: S
authors.lastname: Soize
authors.affiliation: Department of radiology, Hôpital Maison Blanche, Université de Champagne-Ardenne, Reims, France.
authors.forename: Krzysztof
authors.initials: K
authors.lastname: Kadziolka
authors.affiliation: CReSTIC SIC EA3804, Université de Champagne-Ardenne, Reims, France.
authors.forename: Christophe
authors.initials: C
authors.lastname: Portefaix
authors.affiliation: Department of radiology, Hôpital Maison Blanche, Université de Champagne-Ardenne, Reims, France.
authors.forename: Laurent
authors.initials: L
authors.lastname: Pierot
mesh_terms: D000328:Adult; D000368:Aged; D015901:Angiography, Digital Subtraction / Q000379:methods / Q000592:standards*; D002533:Cerebral Angiography / Q000379:methods / Q000592:standards*; D002560:Cerebrovascular Circulation / Q000502:physiology*; D057510:Endovascular Procedures / Q000379:methods*; D005260:Female; D005500:Follow-Up Studies; D006801:Humans; D007089:Image Enhancement; D021621:Imaging, Three-Dimensional; D002532:Intracranial Aneurysm / Q000175:diagnosis* / Q000628:therapy*; D018810:Magnetic Resonance Angiography / Q000379:methods / Q000592:standards*; D008297:Male; D008875:Middle Aged; D012680:Sensitivity and Specificity; D016896:Treatment Outcome
keywords: Aneurysm; Flow Diverter; Magnetic Resonance Angiography