title: Multimodal visibility of a modified polyzene-F-coated spherical embolic agent for liver embolization: feasibility study in a porcine model.
abstract: OBJECTIVE
  To evaluate multimodal visibility of modified currently available microspheres on radiography, magnetic resonance (MR) imaging, and computed tomography (CT) in a porcine liver model.
  
  
  METHODS
  Livers of four pigs were embolized with two sizes (100 μm ± 25 and 700 μm ± 50) of modified Embozene Microspheres embedded with different densities of barium sulfate and iodine as radiopaque materials (intensity groups A-C, with increasing intensity from A to C for 100 μm and intensities A and C for 700 μm) and iron oxide as magnetic substance for MR imaging visibility. Pigs embolized with currently available Embozene Microspheres served as control groups. Pre- and postinterventional MR imaging (T1- and T2-weighted) and CT were performed. Qualitative and quantitative (ie, determination of signal-to-noise ratio [SNR]) particle visibility was evaluated on radiography, MR imaging, and CT.
  
  
  RESULTS
  Modified particles of both sizes were visible on radiography, MR imaging, and CT. Particles in the control group were not visible. For modified particles of both sizes, SNRs measured on MR imaging decreased significantly after embolization (eg, cluster analysis of group A, 100 μm ± 50 particles, T1-weighted, -74.6% ± 3.4; P = .03). For modified particles of both sizes, SNR measured on CT increased significantly after embolization (eg, cluster analysis of group A, 700 μm ± 25 particles, +54.3% ± 13.5; P = .03).
  
  
  CONCLUSIONS
  Modification of currently available Embozene Microspheres was successful, with multimodal visibility on radiography, MR imaging, and CT in porcine liver. In the future, this might improve procedure accuracy and allow monitoring, control, and improvement of embolotherapy during and after the procedure.
authors: Department of Diagnostic and Interventional Radiology, University Hospital Heidelberg, Heidelberg, Germany. ulrike.stampfl@med.uni-heidelberg.de
authors: Ulrike
authors: U
authors: Stampfl
authors: Christof-Matthias
authors: CM
authors: Sommer
authors: Nadine
authors: N
authors: Bellemann
authors: Maria
authors: M
authors: Holzschuh
authors: Alexander
authors: A
authors: Kueller
authors: Jacques
authors: J
authors: Bluemmel
authors: Tobias
authors: T
authors: Gehrig
authors: Maxim
authors: M
authors: Shevchenko
authors: Hannes
authors: H
authors: Kenngott
authors: Hans-Ulrich
authors: HU
authors: Kauczor
authors: Boris
authors: B
authors: Radeleff
mesh_terms: D015901:Angiography, Digital Subtraction; D000818:Animals; D001466:Barium Sulfate; D020099:Coated Materials, Biocompatible; D003287:Contrast Media; D004621:Embolization, Therapeutic / Q000379:methods*; D005240:Feasibility Studies; D005260:Female; D006499:Hepatic Artery / Q000000981:diagnostic imaging*; D007269:Injections, Intra-Arterial; D008099:Liver / Q000098:blood supply*; D008279:Magnetic Resonance Imaging; D008422:Materials Testing; D008863:Microspheres; D023421:Models, Animal; D009943:Organophosphorus Compounds / Q000008:administration & dosage* / Q000737:chemistry; D010316:Particle Size; D011108:Polymers / Q000008:administration & dosage* / Q000737:chemistry; D015641:Radiography, Interventional; D059629:Signal-To-Noise Ratio; D034421:Sus scrofa; D014057:Tomography, X-Ray Computed
chemical_list: D020099:Coated Materials, Biocompatible; D003287:Contrast Media; D009943:Organophosphorus Compounds; D011108:Polymers; D001466:Barium Sulfate