title: CE-MRA for follow-up of aneurysms post stent-assisted coiling.
abstract: This study compared the accuracy of contrast-enhanced MR angiography (CE-MRA) to intra-arterial cerebral angiography (IA-DSA) for assessment of intracranial aneurysms after stent-assisted coiling and to check if the presence of a stent in the parent artery diminishes the accuracy of CE-MRA. Consecutive patients with cerebral aneurysms treated by stent-assisted coiling were evaluated retrospectively. Matching follow-up CE-MRA and IA-DSA were evaluated separately. Evaluation included the presence of aneurysmal remnant, patency and stenosis of parent artery. Twenty-seven patients with 28 aneurysms and 33 matched CE-MRA and IA-DSA studies were evaluated. Nineteen aneurysmal remnants were seen on CE-MRA and 16 on IA-DSA. CE-MRA diagnosed three aneurysmal remnants not appreciated on IA-DSA. Five other remnants were larger on CE-MRA than IA-DSA. None of the remnants were missed on CE-MRA. Parent arteries were patent on both modalities. CE-MRA showed false stenosis of the stented artery in six cases and exaggerated stenosis in two. In 18 cases, CE-MRA showed a short focal "pseudo-stenosis" where the stent's marker bands were located. This was noted whenever the stent's marker bands were located in an artery with luminal diameter ≤2 mm and was called "marker band effect". CE-MRA is an accurate technique for follow-up of aneurysms post stent-assisted coiling with excellent depiction of remnants in spite of the presence of a stent. Apparent stenosis of the stented parent artery on CE-MRA is often false or exaggerated. "Marker band effect" should be recognized as an artifact that appears when stent's marker bands are in a small artery.
authors.affiliation: Department of Medical Imaging, Toronto Western Hospital, Toronto, Ontario, Canada. ronit.agid@uhn.ca
authors.forename: R
authors.initials: R
authors.lastname: Agid
authors.forename: M
authors.initials: M
authors.lastname: Schaaf
authors.forename: Ri
authors.initials: R
authors.lastname: Farb
mesh_terms: D000328:Adult; D000368:Aged; D002533:Cerebral Angiography / Q000379:methods*; D003287:Contrast Media; D004621:Embolization, Therapeutic / Q000379:methods*; D005260:Female; D006801:Humans; D002532:Intracranial Aneurysm / Q000175:diagnosis* / Q000000981:diagnostic imaging / Q000628:therapy*; D007472:Iohexol; D018810:Magnetic Resonance Angiography / Q000379:methods*; D008297:Male; D008875:Middle Aged; D012189:Retrospective Studies; D015607:Stents; D016896:Treatment Outcome; D014654:Vascular Patency
chemical_list: D003287:Contrast Media; D007472:Iohexol