title: Collagen microbeads: experimental evaluation of an embolic agent in the rete mirabile of the swine.
abstract: OBJECTIVE
  To evaluate the histologic and angiographic effects of collagen microbeads as an embolic agent in the swine rete mirabile.
  
  
  METHODS
  Human collagen particles (380 +/- 100 microns) of spheroidal shape and smooth surface were used to embolize the rete mirabile in five swine. Control angiograms and pathologic examinations were obtained immediately and sequentially from 3 to 35 days after embolization.
  
  
  RESULTS
  The collagen particles were easy to inject through microcatheters. Embolization was always angiographically complete and persistent for at least 5 weeks. Histologic studies showed occlusion of 25% to 50% of the rete vessels. After 3 and 5 weeks' follow-up, transmural and adventitial chronic inflammation was present. Inflammatory infiltrates included lymphohistiocytic cells and scattered eosinophils. The foreign-body giant-cell reaction was pronounced. No evidence of angionecrosis or focal hemorrhage was shown.
  
  
  CONCLUSIONS
  Collagen microbeads are a promising experimental embolic agent, with potential future applications in humans.
authors.affiliation: Department of Radiological Sciences (Endovascular Therapy), University of California at Los Angeles Medical Center, USA.
authors.forename: F
authors.initials: F
authors.lastname: Turjman
authors.forename: T F
authors.initials: TF
authors.lastname: Massoud
authors.forename: H V
authors.initials: HV
authors.lastname: Vinters
authors.forename: C
authors.initials: C
authors.lastname: Ji
authors.forename: M
authors.initials: M
authors.lastname: Tardy
authors.forename: G
authors.initials: G
authors.lastname: Guglielmi
authors.forename: F
authors.initials: F
authors.lastname: Viñuela
mesh_terms: D000818:Animals; D001921:Brain / Q000098:blood supply*; D002343:Carotid Artery, Internal / Q000000981:diagnostic imaging / Q000473:pathology; D002941:Circle of Willis / Q000000981:diagnostic imaging / Q000473:pathology; D003094:Collagen; D004621:Embolization, Therapeutic / Q000379:methods*; D005549:Foreign-Body Reaction / Q000473:pathology; D015745:Granuloma, Foreign-Body / Q000000981:diagnostic imaging / Q000473:pathology; D006801:Humans; D008855:Microscopy, Electron, Scanning; D008863:Microspheres; D010316:Particle Size; D010614:Pharynx / Q000098:blood supply; D011859:Radiography; D013499:Surface Properties; D013552:Swine
chemical_list: D003094:Collagen