title: Non-enhanced magnetic resonance imaging of unruptured intracranial aneurysms at 7 Tesla: Comparison with digital subtraction angiography.
abstract: OBJECTIVE
  To prospectively evaluate non-contrast-enhanced 7-Tesla (T) MRA for delineation of unruptured intracranial aneurysms (UIAs) in comparison with DSA.
  
  
  METHODS
  Forty patients with single or multiple UIAs were enrolled in this IRB-approved trial. Sequences acquired at 7 T were TOF MRA and non-contrast-enhanced MPRAGE. All patients additionally underwent 3D rotational DSA. Two neuroradiologists individually analysed the following aneurysm and image features on a five-point scale in 2D and 3D image reconstructions: delineation of parent vessel, dome and neck; overall image quality; presence of artefacts. Interobserver accordance was assessed by the kappa coefficient.
  
  
  RESULTS
  A total of 64 UIAs were detected in DSA and in all 2D and 3D MRA image reconstructions. Ratings showed comparable results for DSA and 7-T MRA when considering all image reconstructions. Highest ratings for individual image reconstructions were given for 2D MPRAGE and 3D TOF MRA. Interobserver accordance was almost perfect for the majority of ratings.
  
  
  CONCLUSIONS
  This study demonstrates excellent delineation of UIAs using 7-T MRA within a clinical setting comparable to the gold standard, DSA. The combination of 7-T non-enhanced MPRAGE and TOF MRA for assessment of untreated UIAs is a promising clinical application of ultra-high-field MRA.
  
  
  CONCLUSIONS
  • Non-enhanced 7-T MRA allowed excellent delineation of unruptured intracranial aneurysms (UIAs). • Image quality at 7-T was comparable with DSA considering both sequences. • Assessment of UIAs is a promising clinical application of ultra-high-field MRA.
authors.affiliation: Erwin L. Hahn Institute for Magnetic Resonance Imaging, University Duisburg-Essen, 45141, Essen, Germany. karsten.wrede@uk-essen.de.|Department of Neurosurgery, University Hospital Essen, Hufelandstrasse 55, 45147, Essen, Germany. karsten.wrede@uk-essen.de.
authors.forename: Karsten H
authors.initials: KH
authors.lastname: Wrede
authors.affiliation: Erwin L. Hahn Institute for Magnetic Resonance Imaging, University Duisburg-Essen, 45141, Essen, Germany.|Department of Neurosurgery, University Hospital Essen, Hufelandstrasse 55, 45147, Essen, Germany.|Department of Neurosurgery, Graduate School of Biomedical and Health Sciences, Hiroshima University, 734-8553, Hiroshima, Japan.
authors.forename: Toshinori
authors.initials: T
authors.lastname: Matsushige
authors.affiliation: Department of Diagnostic and Interventional Radiology and Neuroradiology, University Hospital Essen, 45147, Essen, Germany.
authors.forename: Sophia L
authors.initials: SL
authors.lastname: Goericke
authors.affiliation: Erwin L. Hahn Institute for Magnetic Resonance Imaging, University Duisburg-Essen, 45141, Essen, Germany.|Department of Neurosurgery, University Hospital Essen, Hufelandstrasse 55, 45147, Essen, Germany.
authors.forename: Bixia
authors.initials: B
authors.lastname: Chen
authors.affiliation: Department of Diagnostic and Interventional Radiology and Neuroradiology, University Hospital Essen, 45147, Essen, Germany.
authors.forename: Lale
authors.initials: L
authors.lastname: Umutlu
authors.affiliation: Erwin L. Hahn Institute for Magnetic Resonance Imaging, University Duisburg-Essen, 45141, Essen, Germany.|High Field and Hybrid MR Imaging, University Hospital Essen, 45147, Essen, Germany.
authors.forename: Harald H
authors.initials: HH
authors.lastname: Quick
authors.affiliation: Erwin L. Hahn Institute for Magnetic Resonance Imaging, University Duisburg-Essen, 45141, Essen, Germany.|Department of Diagnostic and Interventional Radiology and Neuroradiology, University Hospital Essen, 45147, Essen, Germany.|Division of Medical Physics in Radiology (E020), German Cancer Research Center (DKFZ), 69120, Heidelberg, Germany.
authors.forename: Mark E
authors.initials: ME
authors.lastname: Ladd
authors.affiliation: Erwin L. Hahn Institute for Magnetic Resonance Imaging, University Duisburg-Essen, 45141, Essen, Germany.
authors.forename: Sören
authors.initials: S
authors.lastname: Johst
authors.affiliation: Department of Diagnostic and Interventional Radiology and Neuroradiology, University Hospital Essen, 45147, Essen, Germany.
authors.forename: Michael
authors.initials: M
authors.lastname: Forsting
authors.affiliation: Department of Neurosurgery, University Hospital Essen, Hufelandstrasse 55, 45147, Essen, Germany.
authors.forename: Ulrich
authors.initials: U
authors.lastname: Sure
authors.affiliation: Department of Diagnostic and Interventional Radiology and Neuroradiology, University Hospital Essen, 45147, Essen, Germany.|Department of Neuroradiology, University Hospital Giessen, 35385, Giessen, Germany.
authors.forename: Marc
authors.initials: M
authors.lastname: Schlamann
mesh_terms: D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D015901:Angiography, Digital Subtraction / Q000379:methods*; D001921:Brain / Q000000981:diagnostic imaging / Q000473:pathology; D005260:Female; D006801:Humans; D007091:Image Processing, Computer-Assisted; D021621:Imaging, Three-Dimensional / Q000379:methods; D002532:Intracranial Aneurysm / Q000000981:diagnostic imaging* / Q000473:pathology; D018810:Magnetic Resonance Angiography / Q000379:methods*; D008297:Male; D008875:Middle Aged; D011446:Prospective Studies; D015203:Reproducibility of Results; D012680:Sensitivity and Specificity
keywords: 7-T; MPRAGE; Magnetic resonance angiography; Time-of-flight; Unruptured intracranial aneurysm