title: Assessing Blood Flow in an Intracranial Stent: A Feasibility Study of MR Angiography Using a Silent Scan after Stent-Assisted Coil Embolization for Anterior Circulation Aneurysms.
abstract: OBJECTIVE
  Blood flow in an intracranial stent cannot be visualized with 3D time-of-flight MR angiography owing to magnetic susceptibility and radiofrequency shielding. As a novel follow-up tool after stent-assisted coil embolization, we applied MRA by using a Silent Scan algorithm that contains an ultrashort TE combined with an arterial spin-labeling technique (Silent MRA). The purpose of this study was to determine whether Silent MRA could visualize flow in an intracranial stent placed in the anterior circulation.
  
  
  METHODS
  Nine patients treated with stent-assisted coil embolization for anterior circulation aneurysms underwent MRAs (Silent MRA and TOF MRA) and x-ray digital subtraction angiography. MRAs were performed in the same session on a 3T unit. Two neuroradiologists independently reviewed the MRA images and subjectively scored flow in a stent as 1 (not visible) to 4 (excellent) by referring to the latest x-ray digital subtraction angiography image as a criterion standard.
  
  
  RESULTS
  Both observers gave MRA higher scores than TOF MRA for flow in a stent in all cases. The mean score for Silent MRA was 3.44 ± 0.53, and for TOF MRA, it was 1.44 ± 0.46 (P < .001).
  
  
  CONCLUSIONS
  Silent MRA was able to visualize flow in an intracranial stent more effectively than TOF MRA. Silent MRA might be useful for follow-up imaging after stent-assisted coil embolization, though these study results may be only preliminary due to some limitations.
authors.affiliation: From the Departments of Radiology (R.I., M.S., N.T., M.H., K.K., M.T., M. Yoshida, S.S., N.H., S.A.) ririe@juntendo.ac.jp.
authors.forename: R
authors.identifier: http://orcid.org/0000-0001-7402-3983
authors.initials: R
authors.lastname: Irie
authors.affiliation: From the Departments of Radiology (R.I., M.S., N.T., M.H., K.K., M.T., M. Yoshida, S.S., N.H., S.A.).
authors.forename: M
authors.initials: M
authors.lastname: Suzuki
authors.affiliation: Neurosurgery (M. Yamamoto, Y.S., H.O.), Juntendo University Hospital, Tokyo, Japan.
authors.forename: M
authors.initials: M
authors.lastname: Yamamoto
authors.affiliation: From the Departments of Radiology (R.I., M.S., N.T., M.H., K.K., M.T., M. Yoshida, S.S., N.H., S.A.).
authors.forename: N
authors.initials: N
authors.lastname: Takano
authors.affiliation: Neurosurgery (M. Yamamoto, Y.S., H.O.), Juntendo University Hospital, Tokyo, Japan.
authors.forename: Y
authors.initials: Y
authors.lastname: Suga
authors.affiliation: From the Departments of Radiology (R.I., M.S., N.T., M.H., K.K., M.T., M. Yoshida, S.S., N.H., S.A.).
authors.forename: M
authors.identifier: http://orcid.org/0000-0002-1791-8032
authors.initials: M
authors.lastname: Hori
authors.affiliation: From the Departments of Radiology (R.I., M.S., N.T., M.H., K.K., M.T., M. Yoshida, S.S., N.H., S.A.).
authors.forename: K
authors.initials: K
authors.lastname: Kamagata
authors.affiliation: From the Departments of Radiology (R.I., M.S., N.T., M.H., K.K., M.T., M. Yoshida, S.S., N.H., S.A.).
authors.forename: M
authors.initials: M
authors.lastname: Takayama
authors.affiliation: From the Departments of Radiology (R.I., M.S., N.T., M.H., K.K., M.T., M. Yoshida, S.S., N.H., S.A.).
authors.forename: M
authors.initials: M
authors.lastname: Yoshida
authors.affiliation: From the Departments of Radiology (R.I., M.S., N.T., M.H., K.K., M.T., M. Yoshida, S.S., N.H., S.A.).
authors.forename: S
authors.initials: S
authors.lastname: Sato
authors.affiliation: From the Departments of Radiology (R.I., M.S., N.T., M.H., K.K., M.T., M. Yoshida, S.S., N.H., S.A.).
authors.forename: N
authors.initials: N
authors.lastname: Hamasaki
authors.affiliation: Neurosurgery (M. Yamamoto, Y.S., H.O.), Juntendo University Hospital, Tokyo, Japan Department of Neuroendovascular Therapy (H.O.), Juntendo University School of Medicine, Tokyo, Japan.
authors.forename: H
authors.initials: H
authors.lastname: Oishi
authors.affiliation: From the Departments of Radiology (R.I., M.S., N.T., M.H., K.K., M.T., M. Yoshida, S.S., N.H., S.A.).
authors.forename: S
authors.initials: S
authors.lastname: Aoki
mesh_terms: D000328:Adult; D000368:Aged; D000465:Algorithms; D015901:Angiography, Digital Subtraction / Q000379:methods; D002533:Cerebral Angiography / Q000379:methods*; D004621:Embolization, Therapeutic / Q000379:methods*; D005240:Feasibility Studies; D005260:Female; D005500:Follow-Up Studies; D006801:Humans; D002532:Intracranial Aneurysm / Q000175:diagnosis* / Q000601:surgery; D018810:Magnetic Resonance Angiography / Q000379:methods*; D008297:Male; D008875:Middle Aged; D013113:Spin Labels; D015607:Stents
chemical_list: D013113:Spin Labels