title: Volume changes of extremely large and giant intracranial aneurysms after treatment with flow diverter stents.
abstract: BACKGROUND
  This study assessed volume changes of unruptured large and giant aneurysms (greatest diameter >20 mm) after treatment with flow diverter (FD) stents.
  
  
  METHODS
  Clinical audit of the cases treated in a single institution, over a 5-year period. Demographic and clinical data were retrospectively collected from the hospital records. Aneurysm volumes were measured by manual outlining at sequential slices using computerised tomography (CT) or magnetic resonance (MR) angiography data.
  
  
  RESULTS
  The audit included eight patients (seven females) with eight aneurysms. Four aneurysms involved the cavernous segment of the internal carotid artery (ICA), three the supraclinoid ICA and one the basilar artery. Seven patients presented with signs and symptoms of mass effect and one with seizures. All but one aneurysm was treated with a single FD stent; six aneurysms were also coiled (either before or simultaneously with FD placement). Minimum follow-up time was 6 months (mean 20 months). At follow-up, three aneurysms decreased in size, three were unchanged and two increased. Both aneurysms that increased in size showed persistent endosaccular flow at follow-up MR; in one case, failure was attributed to suboptimal position of the stent; in the other case, it was attributed to persistence of a side branch originating from the aneurysm (similar to the endoleak phenomenon of aortic aneurysms). At follow-up, five aneurysms were completely occluded; none of these increased in volume.
  
  
  CONCLUSIONS
  Complete occlusion of the aneurysms leads, in most cases, to its shrinkage. In cases of late aneurysm growth or regrowth, consideration should be given to possible endoleak as the cause.
authors: Oxford Neurovascular and Neuroradiology Research Unit, Nuffield Department of Surgical Sciences, West Wing, John Radcliffe Hospital, Headington, Oxford, OX3 9DU, UK.
authors: Angelo
authors: A
authors: Carneiro
authors: Neil
authors: N
authors: Rane
authors: Wilhelm
authors: W
authors: Küker
authors: Martino
authors: M
authors: Cellerini
authors: Rufus
authors: R
authors: Corkill
authors: James V
authors: JV
authors: Byrne
mesh_terms: D000368:Aged; D001807:Blood Vessel Prosthesis; D002533:Cerebral Angiography / Q000379:methods; D002536:Cerebral Arteries / Q000000981:diagnostic imaging / Q000473:pathology; D002550:Cerebral Veins / Q000000981:diagnostic imaging / Q000473:pathology; D005260:Female; D006801:Humans; D021621:Imaging, Three-Dimensional / Q000379:methods; D002532:Intracranial Aneurysm / Q000175:diagnosis* / Q000473:pathology / Q000628:therapy*; D018810:Magnetic Resonance Angiography / Q000379:methods; D008297:Male; D008875:Middle Aged; D009929:Organ Size; D015203:Reproducibility of Results; D012680:Sensitivity and Specificity; D015607:Stents; D014057:Tomography, X-Ray Computed / Q000379:methods*; D016896:Treatment Outcome