title: Added Value of 3D Proton-Density Weighted Images in Diagnosis of Intracranial Arterial Dissection.
abstract: BACKGROUND
  An early and reliable diagnosis of intracranial arterial dissection is important to reduce the risk of neurological complication. The purpose of this study was to assess the clinical usefulness of three-dimensional high-resolution MRI (3D-HR-MRI) including pre- and post-contrast T1-weighted volumetric isotropic turbo spin echo acquisition with improved motion-sensitized driven equilibrium preparation (3D-iMSDE-T1) and proton-density weighted image (3D-PD) in detecting dissection and to evaluate the added value of 3D-PD in diagnosing intracranial arterial dissection.
  
  
  METHODS
  We retrospectively recruited patients who underwent 3D-HR-MRI with clinical suspicion of arterial dissection. Among them, we selected patients who were diagnosed with definite dissection according to the Spontaneous Cervicocephalic Arterial Dissections Study criteria. For each patient, the presence of intimal flap, intramural hematoma, and vessel dilatation were evaluated independently by two neuroradiologists on each sequence. Interobserver agreement was assessed.
  
  
  RESULTS
  Seventeen patients (mean age: 41 ± 10 [SD] years; 13 men) were diagnosed with definite dissection. The intimal flaps were more frequently detected on 3D-PD (88.2%, 15/17) than on 3D-iMSDE-T1 (29.4%, 5/17), and post-contrast 3D-iMSDE-T1 (35.3%, 6/17; P = 0.006 and P = 0.004, respectively). No significant difference was found in the detection rate of intramural hematomas (59-71%) and vascular dilatations (47%) on each sequence. Interobserver agreement for detection of dissection findings showed almost perfect agreement (k = 0.84-1.00), except for detection of intimal flaps on pre-contrast 3D-iMSDE-T1 (k = 0.62). After addition of 3D-PD to pre- and post-contrast 3D-iMSDE-T1, more patients were diagnosed with definite dissection with the initial MRI (88.2% vs. 47.1%; P = 0.039).
  
  
  CONCLUSIONS
  The intimal flap might be better visualized on the 3D-PD sequence than the 3D-iMSDE-T1 sequences, allowing diagnosis of definite dissection without follow-up imaging.
authors.affiliation: Department of Radiology, Inje University Ilsan Paik Hospital, Goyang, Gyeonggi, Korea.
authors.forename: Jin Woo
authors.initials: JW
authors.lastname: Kim
authors.affiliation: Department of Radiology, Ewha Womans University School of Medicine, Seoul, Korea.
authors.forename: Na-Young
authors.identifier: http://orcid.org/0000-0003-1157-6366
authors.initials: NY
authors.lastname: Shin
authors.affiliation: Department of Neurology, Yonsei University College of Medicine, Seoul, Korea.
authors.forename: Young Dae
authors.initials: YD
authors.lastname: Kim
authors.affiliation: Department of Radiology, Yonsei University College of Medicine, Seoul, Korea.
authors.forename: Seung-Koo
authors.initials: SK
authors.lastname: Lee
authors.affiliation: Department of Radiology, Ewha Womans University School of Medicine, Seoul, Korea.
authors.forename: Soo Mee
authors.initials: SM
authors.lastname: Lim
authors.affiliation: Department of Radiology, Soonchunhyang University Cheonan Hospital, Cheonan, Chungnam, Korea.
authors.forename: Se Won
authors.initials: SW
authors.lastname: Oh
mesh_terms: D000328:Adult; D000784:Aortic Dissection / Q000000981:diagnostic imaging*; D005260:Female; D006801:Humans; D021621:Imaging, Three-Dimensional; D002532:Intracranial Aneurysm / Q000000981:diagnostic imaging*; D020300:Intracranial Hemorrhages / Q000000981:diagnostic imaging*; D008279:Magnetic Resonance Imaging; D008297:Male; D008875:Middle Aged; D012189:Retrospective Studies