title: Flow-diverting stents for intracranial bifurcation aneurysm treatment.
abstract: BACKGROUND
  Although initially considered safe when covering bifurcation sites, flow-diverting stents may provoke thrombosis of side branches that are covered during aneurysm treatment.
  
  
  OBJECTIVE
  To understand the occurrence and clinical expression of side-branch remodeling in distal intracranial arterial sites after flow diverter deployment by means of correlation of imaging and clinical data.
  
  
  METHODS
  We analyzed our prospectively collected data on a series of patients treated with flow diverters for intracranial aneurysms at bifurcation sites. From February 2011 to May 2013, 32 patients with 37 aneurysms (anterior communicating artery, 9 [24.3%]; anterior cerebral artery, 5 [13.5%]; middle cerebral artery, 19 (51.4%); terminal internal carotid artery, 4 [10.8%]) were treated. We divided aneurysms into 2 groups based on the side branches covered by the stent during treatment. Group A consisted of cases with side branches that supplied brain territories also receiving a direct collateral supply. Group B consisted of cases in which side branches supplied territories without direct collateral supply. The 2 groups were compared statistically.
  
  
  RESULTS
  Total exclusion occurred in 97.3% of aneurysms at follow-up. Initial modified Rankin Scale (mRS) score was 0 to 1 for 29 patients (90.6%) and 2 for 3 patients (9.4%). New permanent neurological deficit was reported in 3 patients (9.4%). At the 6-month follow-up, the mRS score was 0 to 1 for 31 patients (96.8%) and 3 for 1 patient (3.2%). Although 78.5% of side branches in group A underwent narrowing or occlusion after 6 months, no new stroke was found on magnetic resonance imaging.
  
  
  CONCLUSIONS
  Symptomatic modifications of side branches after flow diverter treatment depend on the extent and type of collateral supply.
authors.affiliation: *Department of Interventional Neuroradiology, ‡Department of Diagnostic Neuroradiology, and §Department of Neurosurgery, Dupuytren University Hospital, Limoges, France.
authors.forename: Suzana
authors.initials: S
authors.lastname: Saleme
authors.forename: Christina
authors.initials: C
authors.lastname: Iosif
authors.forename: Sanita
authors.initials: S
authors.lastname: Ponomarjova
authors.forename: George
authors.initials: G
authors.lastname: Mendes
authors.forename: Yann
authors.initials: Y
authors.lastname: Camilleri
authors.forename: François
authors.initials: F
authors.lastname: Caire
authors.forename: Marie-Paule
authors.initials: MP
authors.lastname: Boncoeur
authors.forename: Charbel
authors.initials: C
authors.lastname: Mounayer
mesh_terms: D000328:Adult; D000368:Aged; D002533:Cerebral Angiography; D057510:Endovascular Procedures / Q000009:adverse effects / Q000295:instrumentation*; D005260:Female; D006801:Humans; D002532:Intracranial Aneurysm / Q000473:pathology* / Q000601:surgery*; D008279:Magnetic Resonance Imaging; D008297:Male; D008875:Middle Aged; D015607:Stents / Q000009:adverse effects*; D016896:Treatment Outcome; D055815:Young Adult