title: Preoperative embolization of paragangliomas and angiofibromas. Measurement of intratumoral arteriovenous shunts.
abstract: OBJECTIVE
  To determine if technetium Tc 99m-labeled macroaggregated albumin selective angioscintigraphy enables estimation of microparticle-arteriovenous shunt in branchial paragangliomas and nasopharyngeal angiofibromas.
  
  
  METHODS
  Technetium Tc 99m-labeled macroaggregated albumin particles with calibrated diameters between 25 and 50 microns were administered during selective catheterization of the feeding arteries in 4 branchial paragangliomas (glomus tumors) and 4 nasopharyngeal angiofibromas. Preliminary measures of the activity of the tumor region and of the lungs were obtained in the angiography suite using a hand-held detector. Without changing the position of the microcatheter, definitive embolization was performed. After endovascular treatment, scintigraphy was performed and the pulmonary shunt index was calculated with the use of a gamma camera and a dedicated computer program.
  
  
  RESULTS
  The pulmonary shunt index varied between 0% and 36% for branchial paragangliomas (glomus tumors) and between 82% and 95% for angiofibromas.
  
  
  CONCLUSIONS
  Our results provide new evidence that the incidence of microparticle-arteriovenous shunt in nasopharyngeal angiofibromas is much higher than in paragangliomas.
authors.affiliation: Department of Neuroradiology, University of Bern, Switzerland.
authors.forename: G
authors.initials: G
authors.lastname: Schroth
authors.forename: A R
authors.initials: AR
authors.lastname: Haldemann
authors.forename: L
authors.initials: L
authors.lastname: Mariani
authors.forename: L
authors.initials: L
authors.lastname: Remonda
authors.forename: J
authors.initials: J
authors.lastname: Raveh
mesh_terms: D000293:Adolescent; D000368:Aged; D018322:Angiofibroma / Q000098:blood supply / Q000000981:diagnostic imaging / Q000601:surgery / Q000628:therapy*; D001934:Branchial Region; D004621:Embolization, Therapeutic; D005260:Female; D005918:Glomus Tumor / Q000098:blood supply / Q000000981:diagnostic imaging / Q000601:surgery / Q000628:therapy*; D006801:Humans; D018810:Magnetic Resonance Angiography; D008297:Male; D008875:Middle Aged; D009303:Nasopharyngeal Neoplasms / Q000098:blood supply / Q000000981:diagnostic imaging / Q000601:surgery / Q000628:therapy*; D010235:Paraganglioma / Q000098:blood supply / Q000000981:diagnostic imaging / Q000601:surgery / Q000628:therapy*; D011446:Prospective Studies; D011877:Radionuclide Imaging; D013668:Technetium Tc 99m Aggregated Albumin
chemical_list: D013668:Technetium Tc 99m Aggregated Albumin