title: MR angiography in the follow-up of coiled cerebral aneurysms after treatment with Guglielmi detachable coils.
abstract: OBJECTIVE
  Intra-arterial digital subtraction angiography (DSA) has been considered the gold standard examination in the follow-up of patients treated with Guglielmi detachable coils (GDCs). However, DSA is an invasive and expensive investigation and results in exposure to ionising radiation to both patient and operator. The aim of this study was to compare MR angiography (MRA) with DSA with regard to patency of the occlusion of aneurysms following GDC treatment.
  
  
  METHODS
  We performed 75 MRA and DSA examinations on 51 patients treated with GDCs. The examinations were performed 3-36 months after embolisation and the interval between MRA and DSA was less than 1 week. Hard copies of both studies were interpreted retrospectively and independently for residual flow within the aneurysm, residual aneurysmal neck, and parent and branch vessel flow.
  
  
  RESULTS
  Patency status of parent and branch vessel flow was correctly identified with MRA in all patients except 1. The sensitivity of MRA in revealing residual flow within the aneurysm was 97%. The specificity in ruling out residual flow within the aneurysm was 91%.
  
  
  CONCLUSIONS
  MRA may replace DSA in the long-term follow-up of coiled cerebral aneurysms. The initial follow-up examination should, however, include both modalities.
authors.affiliation: Department of Radiology, Section of Neuroradiology, The National Hospital, University of Oslo, Sognsvannsveien 20, NO-0027 Oslo, Norway.
authors.forename: Terje
authors.initials: T
authors.lastname: Nome
authors.forename: S J
authors.initials: SJ
authors.lastname: Bakke
authors.forename: P H
authors.initials: PH
authors.lastname: Nakstad
mesh_terms: D015901:Angiography, Digital Subtraction; D019917:Blood Vessel Prosthesis Implantation; D002560:Cerebrovascular Circulation / Q000502:physiology; D005500:Follow-Up Studies; D006801:Humans; D002532:Intracranial Aneurysm / Q000175:diagnosis* / Q000503:physiopathology / Q000601:surgery*; D018810:Magnetic Resonance Angiography; D012189:Retrospective Studies; D012680:Sensitivity and Specificity; D016896:Treatment Outcome; D014654:Vascular Patency / Q000502:physiology