title: Partition of calibrated tris-acryl gelatin microspheres in the arterial vasculature of embolized nasopharyngeal angiofibromas and paragangliomas.
abstract: OBJECTIVE
  To determine the location of calibrated tris-acryl gelatin microspheres (TGMs) in the arterial vasculature of nasopharyngeal angiofibromas (NAFs) and paragangliomas (PGs).
  
  
  METHODS
  Forty-nine specimens (25 PGs and 24 NAFs) treated operatively after embolization with TGMs of various sizes (100-300 microm to 900-1200 microm) were stained with hematoxylin and eosin saffron and analyzed at an objective magnification of 10 or 20 with a micrometric eyepiece (magnification, x12.5). The diameter of occluded vessels, their localization (intra- or extratumoral), and the number and diameter of TGMs they contained were determined.
  
  
  RESULTS
  Embolized vessels (N = 1125) were measured: 440 in PGs and 685 in NAFs. Vessels were 89% intratumoral and 11% extratumoral. The diameter of the occluded vessels increased significantly with the size range of TGMs used for embolization for each tumor type (P < .0001). Intratumoral occluded vessels were significantly smaller than extratumoral vessels (P < .0001). Distribution of TGMs within the vascular network (intratumoral or extratumoral location) were similar for NAFs and PGs. The intratumoral and extratumoral dissemination of TGMs was different when comparing 100-300-microm TGMs versus 500-700-microm TGMs (P = .0006) as well as 300-500-microm TGMs versus 500-700-microm TGMs (P = .0001).
  
  
  CONCLUSIONS
  The size of the vessels occluded by TGMs and their intra- or extratumoral location directly depend on the size of the injected TGMs. The vessels located inside the tumors were smaller than those located outside the tumors. A threshold for the intratumoral penetration of TGMs in the vasculature can be proposed from these data. There was no evidence of different behavior of TGMs in NAFs versus PGs.
authors.affiliation: Department of Interventional Neuroradiology, Hôpital Lariboisière, AP-HP, 2 rue Ambroise Paré, 75475 Paris Cedex 10, France. alex.laurent@lrb.ap-hop-paris.fr
authors.forename: Alexandre
authors.initials: A
authors.lastname: Laurent
authors.forename: Michel
authors.initials: M
authors.lastname: Wassef
authors.forename: Rene
authors.initials: R
authors.lastname: Chapot
authors.forename: Yabing
authors.initials: Y
authors.lastname: Wang
authors.forename: Emmanuel
authors.initials: E
authors.lastname: Houdart
authors.forename: Ling
authors.initials: L
authors.lastname: Feng
authors.forename: Patrice
authors.initials: P
authors.lastname: Tran Ba Huy
authors.forename: Jean-Jacques
authors.initials: JJ
authors.lastname: Merland
mesh_terms: D000180:Acrylic Resins / Q000737:chemistry / Q000627:therapeutic use*; D000293:Adolescent; D000328:Adult; D000368:Aged; D018322:Angiofibroma / Q000098:blood supply* / Q000628:therapy; D000792:Angiography; D001158:Arteries / Q000473:pathology; D002648:Child; D004396:Coloring Agents; D004621:Embolization, Therapeutic / Q000379:methods*; D005456:Fluorescent Dyes; D005780:Gelatin / Q000737:chemistry / Q000627:therapeutic use*; D006801:Humans; D008863:Microspheres; D008875:Middle Aged; D009303:Nasopharyngeal Neoplasms / Q000098:blood supply* / Q000628:therapy; D010235:Paraganglioma / Q000098:blood supply* / Q000628:therapy; D012189:Retrospective Studies; D013499:Surface Properties
chemical_list: D000180:Acrylic Resins; D004396:Coloring Agents; D005456:Fluorescent Dyes; C496735:trisacryl gelatin microspheres; D005780:Gelatin