title: Simultaneous dual-isotope SPECT/CT with (99m)Tc- and (111)In-labelled albumin microspheres in treatment planning for SIRT.
abstract: OBJECTIVE
  To investigate simultaneous dual-isotope SPECT/CT with two differently radioisotope-labelled albumin-microsphere fractions for treatment planning of hepatic radioembolisation.
  
  
  METHODS
  In addition to (99m)Technetium-labelled albumin microspheres (commercially available), we performed labelling with (111)Indium. Binding stability of (111)Indium-labelled microspheres was tested in vitro and in vivo in mice. Simultaneous dual-isotope SPECT/CT imaging was validated in an anthropomorphic torso phantom; subsequently, dual-isotope SPECT/CT was performed under in-vivo conditions in pigs (n = 3) that underwent transarterial injection of (99m)Technetium- and (111)Indium-labelled microspheres in the liver (right and left hepatic artery, respectively), in both kidneys and in the gluteal musculature. In total, n = 18 transarterial injections were performed.
  
  
  RESULTS
  In-vitro testing and in-vivo studies in mice documented high binding stability for both (99m)Technetium-labelled and (111)Indium-labelled microsphere fractions. In phantom studies, simultaneous dual-isotope SPECT/CT enabled reliable separation of both isotopes. In pigs, the identified deposition of both isotopes could be accurately matched with intended injection targets (100 %, 18/18 intended injection sites). Furthermore, an incidental deposition of (99m)Technetium-labelled microspheres in the stomach could be correlated to the test injection into a right hepatic artery.
  
  
  CONCLUSIONS
  Simultaneous dual-isotope SPECT/CT after transarterial injection with (99m)Technetium- and (111)Indium-labelled microspheres is feasible. Thus, it may offer additional, valuable information compared to single (99m)Technetium-labelled albumin examinations.
  
  
  CONCLUSIONS
  • Simultaneous dual-isotope SPECT/CT with (111) In- and (99m) Tc-labelled albumin microspheres is feasible. • Differentiation of two microsphere fractions after transarterial injection is possible. • The origin of an extra-hepatic microsphere deposition can be correlated to the corresponding artery. • This technique could reduce the setup time for selective internal radiation treatment.
authors.affiliation: Department of Nuclear Medicine, RWTH-Aachen University, Aachen, Germany, mpalmowski@ukaachen.de.
authors.forename: Moritz
authors.initials: M
authors.lastname: Palmowski
authors.forename: Andreas
authors.initials: A
authors.lastname: Goedicke
authors.forename: Andreas
authors.initials: A
authors.lastname: Vogg
authors.forename: Götz
authors.initials: G
authors.lastname: Christ
authors.forename: Georg
authors.initials: G
authors.lastname: Mühlenbruch
authors.forename: Hans J
authors.initials: HJ
authors.lastname: Kaiser
authors.forename: Rolf W
authors.initials: RW
authors.lastname: Günther
authors.forename: Christiane K
authors.initials: CK
authors.lastname: Kuhl
authors.forename: Felix M
authors.initials: FM
authors.lastname: Mottaghy
authors.forename: Florian F
authors.initials: FF
authors.lastname: Behrendt
mesh_terms: D000418:Albumins; D000818:Animals; D000970:Antineoplastic Agents / Q000008:administration & dosage; D016461:Chemoembolization, Therapeutic / Q000379:methods*; D059248:Chemoradiotherapy; D005260:Female; D006801:Humans; D007205:Indium Radioisotopes / Q000627:therapeutic use; D008114:Liver Neoplasms, Experimental / Q000175:diagnosis* / Q000628:therapy; D051379:Mice; D008863:Microspheres; D019275:Radiopharmaceuticals; D011880:Radiotherapy Planning, Computer-Assisted / Q000379:methods*; D013552:Swine; D017256:Technetium Tc 99m Sestamibi; D015899:Tomography, Emission-Computed, Single-Photon / Q000379:methods*; D014057:Tomography, X-Ray Computed / Q000379:methods*
chemical_list: D000418:Albumins; D000970:Antineoplastic Agents; D007205:Indium Radioisotopes; D019275:Radiopharmaceuticals; D017256:Technetium Tc 99m Sestamibi