title: The impact of an antireflux catheter on target volume particulate distribution in liver-directed embolotherapy: a pilot study.
abstract: OBJECTIVE
  To determine if there are differences in hepatic distribution of embolic particles following infusion with a standard end-hole catheter versus an antireflux microcatheter.
  
  
  METHODS
  This prospective study included nine patients (age, 48-86 y) enrolled for treatment of hepatocellular carcinoma (n = 6), liver-dominant metastatic disease (n = 2), or intrahepatic cholangiocarcinoma (n = 1) with resin yttrium-90 ((90)Y) microspheres. Before (90)Y treatment, each patient received two same-day sequential lobar infusions of technetium 99m ((99m)Tc) macroaggregated albumin (MAA) via a conventional end-hole catheter and an antireflux microcatheter positioned at the same location. Differences in technetium 99m-MAA distribution within tumor and nontarget sites were evaluated by single-photon emission computed tomography (SPECT) on a qualitative and semiquantitative basis. The antireflux microcatheter was used for the ensuing (90)Y treatment, with posttreatment (90)Y positron emission tomography/computed tomography to assess distribution of (90)Y microspheres.
  
  
  RESULTS
  Decreases in hepatic nontarget embolization were found in all patients when the antireflux catheter was used. These decreases ranged from a factor of 0.11 to a factor of 0.76 (mean, 0.42; σ = 0.19), representing a 24%-89% reduction. Increased tumor deposition was also noted in all patients, ranging from a factor of 1.33 to a factor of 1.90 (mean, 1.68; σ = 0.20), representing a relative increase of 33%-90%. Both findings were statistically significant (P < .05).
  
  
  CONCLUSIONS
  Although this pilot study identified differences in the downstream distribution of embolic particles when the antireflux catheter was used, further investigation is needed to determine if these findings are reproducible in a larger patient cohort and, if so, whether they are associated with any clinical impact.
authors: Department of Radiology, University of Tennessee Medical Center, Knoxville, Tennessee; Department of Radiology. Electronic address: alexander.pasciak@gmail.com.
authors: Alexander S
authors: AS
authors: Pasciak
authors: Department of Radiology.
authors: James H
authors: JH
authors: McElmurray
authors: Department of Radiology.
authors: Austin C
authors: AC
authors: Bourgeois
authors: Department of Biostatistics, University of Tennessee Graduate School of Medicine, Knoxville, Tennessee.
authors: R Eric
authors: RE
authors: Heidel
authors: Department of Radiology.
authors: Yong C
authors: YC
authors: Bradley
mesh_terms: D000368:Aged; D000369:Aged, 80 and over; D057785:Catheters; D004621:Embolization, Therapeutic / Q000379:methods*; D006801:Humans; D008099:Liver / Q000737:chemistry; D008875:Middle Aged; D052638:Particulate Matter / Q000032:analysis*; D010865:Pilot Projects; D049268:Positron-Emission Tomography; D011446:Prospective Studies; D013668:Technetium Tc 99m Aggregated Albumin; D015899:Tomography, Emission-Computed, Single-Photon; D015021:Yttrium Radioisotopes
chemical_list: D052638:Particulate Matter; D013668:Technetium Tc 99m Aggregated Albumin; D015021:Yttrium Radioisotopes