title: Partial thrombosis of canine carotid bifurcation aneurysms with cellulose acetate polymer.
abstract: OBJECTIVE
  To investigate the usefulness of a cellulose acetate polymer (CAP) solution for partial thrombosis of aneurysms.
  
  
  METHODS
  We created 14 canine cervical carotid bifurcation aneurysms, 11 of which were subsequently thrombosed partially with CAP solution. We then conducted angiographic and histological investigations.
  
  
  RESULTS
  Nine aneurysms were thrombosed 50 to 70% by volume, although a significant crescent crevice between the aneurysmal sac and the CAP mass was left in four of the aneurysms. In the remaining two aneurysms in which a crescent crevice had been seen in the initial stage of CAP injection, 80% and more than 95% thrombosis were needed to occlude the crevice, respectively. Follow-up angiograms of the seven aneurysms with no crescent crevice revealed no shifts of position of the CAP mass toward the bottom of the aneurysm sac, but slight ballooning of the remnants was observed in two of them. The angiograms of the other four aneurysms with significant crescent crevices demonstrated rupture with a massive hematoma in one and shifts of the CAP mass with marked enlargement of remnants in three. Histologically, the seven aneurysms with no enlarged remnants had newly developed membranes consisting of endothelium, infiltrated spindle-shaped cells, collagen, and elastic fibers. In contrast, in the three markedly enlarged aneurysms, there were only recent clots between the CAP mass and the aneurysm lumen and no development of endothelium.
  
  
  CONCLUSIONS
  Partial thrombosis with CAP solution is useful to keep aneurysms in a stable configuration, unless a crescent crevice has been left.
authors.affiliation: Department of Neurological Surgery, Okayama University Medical School, Japan.
authors.forename: K
authors.initials: K
authors.lastname: Tokunaga
authors.forename: K
authors.initials: K
authors.lastname: Kinugasa
authors.forename: S
authors.initials: S
authors.lastname: Mandai
authors.forename: A
authors.initials: A
authors.lastname: Handa
authors.forename: N
authors.initials: N
authors.lastname: Hirotsune
authors.forename: T
authors.initials: T
authors.lastname: Ohmoto
mesh_terms: D000783:Aneurysm / Q000628:therapy*; D000818:Animals; D017536:Carotid Artery, Common / Q000000981:diagnostic imaging / Q000473:pathology; D002482:Cellulose / Q000031:analogs & derivatives* / Q000627:therapeutic use; D004285:Dogs; D004621:Embolization, Therapeutic / Q000379:methods*; D004730:Endothelium, Vascular / Q000473:pathology; D005069:Evaluation Studies as Topic; D011108:Polymers; D019736:Prostheses and Implants; D011859:Radiography
chemical_list: D011108:Polymers; C005062:acetylcellulose; D002482:Cellulose