title: Embolic effects of transcatheter mesenteric arterial embolization with microspheres on the small bowel in a dog model.
abstract: OBJECTIVE
  To determine the arterial distribution and ischemic effects of various particle sizes after transcatheter embolization of the small bowel in a dog model.
  
  
  METHODS
  In 10 dogs, selective microsphere embolization was performed in six branches of the superior mesenteric artery. Microspheres were allocated into three size ranges (100-300 μm, 300-500 μm, and 500-700 μm) and four volume concentrations (0.625%, 1.25%, 2.5%, and 5%). For each size and volume concentration, embolization was performed of five branches at the origin of the last arcade. The distribution of microspheres and the range of ischemic changes of mucosa were evaluated histologically. Angiograms were categorized into two groups: group A, only the vasa recta nonopacified; group B, the last arcade or more proximal branches nonopacified.
  
  
  RESULTS
  Microspheres sized 100-300 μm penetrated into intramural arteries and 500-700 μm microspheres mainly blocked arteries in the mesentery. There was a significant difference among three sizes in terms of the locations within the vasculature (P < .0001). The larger volume and the smaller size resulted in more ischemia. The range of ischemic changes among three sizes and among four volume concentrations was significantly different (P = .004 and P < .0001, respectively). The range of ischemic changes with 500-700 μm microspheres in group B was significantly greater than in group A (0% in group A vs 83% in group B, P = .001).
  
  
  CONCLUSIONS
  In a dog model, embolization of the small bowel limited to the vasa recta with the use if 500-700 μm microspheres reduced the range of ischemic changes.
authors.affiliation: Department of Diagnostic and Interventional Radiology, Osaka University Graduate School of Medicine, 2-2 Yamadaoka Suita, Osaka 565-0871, Japan. Electronic address: k-kishimoto@radiol.med.osaka-u.ac.jp.
authors.forename: Kentaro
authors.initials: K
authors.lastname: Kishimoto
authors.affiliation: Department of Diagnostic and Interventional Radiology, Osaka University Graduate School of Medicine, 2-2 Yamadaoka Suita, Osaka 565-0871, Japan.
authors.forename: Keigo
authors.initials: K
authors.lastname: Osuga
authors.affiliation: Department of Diagnostic and Interventional Radiology, Osaka University Graduate School of Medicine, 2-2 Yamadaoka Suita, Osaka 565-0871, Japan.
authors.forename: Noboru
authors.initials: N
authors.lastname: Maeda
authors.affiliation: Laboratory of Veterinary Surgery, Department of Graduate School of Life and Environmental Sciences, Osaka Prefecture University, Osaka, Japan.
authors.forename: Yoshiyuki
authors.initials: Y
authors.lastname: Higashi
authors.affiliation: Laboratory of Veterinary Surgery, Department of Graduate School of Life and Environmental Sciences, Osaka Prefecture University, Osaka, Japan.
authors.forename: Akiyoshi
authors.initials: A
authors.lastname: Hayashi
authors.affiliation: Department of Pathology, Osaka University Graduate School of Medicine, 2-2 Yamadaoka Suita, Osaka 565-0871, Japan.
authors.forename: Yumiko
authors.initials: Y
authors.lastname: Hori
authors.affiliation: Department of Diagnostic and Interventional Radiology, Osaka University Graduate School of Medicine, 2-2 Yamadaoka Suita, Osaka 565-0871, Japan.
authors.forename: Masahisa
authors.initials: M
authors.lastname: Nakamura
authors.affiliation: Laboratory of Veterinary Surgery, Department of Graduate School of Life and Environmental Sciences, Osaka Prefecture University, Osaka, Japan.
authors.forename: Fumihito
authors.initials: F
authors.lastname: Ohashi
authors.affiliation: Department of Pathology, Osaka University Graduate School of Medicine, 2-2 Yamadaoka Suita, Osaka 565-0871, Japan.
authors.forename: Eiichi
authors.initials: E
authors.lastname: Morii
authors.affiliation: Department of Diagnostic and Interventional Radiology, Osaka University Graduate School of Medicine, 2-2 Yamadaoka Suita, Osaka 565-0871, Japan.
authors.forename: Noriyuki
authors.initials: N
authors.lastname: Tomiyama
mesh_terms: D000818:Animals; D004285:Dogs; D004621:Embolization, Therapeutic / Q000379:methods*; D007421:Intestine, Small / Q000098:blood supply* / Q000000981:diagnostic imaging*; D017538:Mesenteric Artery, Superior / Q000000981:diagnostic imaging*; D008863:Microspheres; D023421:Models, Animal; D011859:Radiography