title: Initial computed tomography imaging experience using a new macromolecular iodinated contrast medium in experimental breast cancer.
abstract: OBJECTIVE
  The objective of this study was to evaluate computed tomography (CT) enhancement characteristics for a new iodinated macromolecular contrast medium (MMCM), PEG12000-Gen4-triiodo, for angiographic effect and for assessment of abnormal vascular permeability in cancer.
  
  
  METHODS
  Time persistence of angiographic effect was evaluated on rat CT images acquired over 30 minutes using the iodinated polyethyleneglycol- (PEG) based macromolecule. Dynamic CT imaging after PEG12000-Gen4-triiodo-enhancement in tumor-bearing rats was used to quantitatively estimate plasma volume and microvascular transendothelial permeability for both tumor and normal soft tissue. Using identical doses of iodine, 300 mg iodine/kg, blood curves for this MMCM and iohexol were compared.
  
  
  RESULTS
  Serial whole-body CT angiograms using PEG12000-Gen4-triiodo showed diagnostic vascular detail through 20 minutes, and the blood enhancement curve was higher and more persistent than with small-molecular iohexol. Permeability estimates were significantly (P<0.02; paired t test) higher in tumors (48.2+/-18.1 microL/min-1 100 mL) than in muscle (2.5+/-5.7 microL/min-1 100 mL).
  
  
  CONCLUSIONS
  Use of PEG-based MMCM for experimental CT allowed for a persistent angiographic enhancement and for quantitative estimation of tumor microvascular characteristics.
authors.affiliation: Center for Pharmaceutical and Molecular Imaging (CPMI), Department of Radiology, University of California San Francisco, San Francisco, California 94143, USA. gsimon@radiology.ucsf.edu
authors.forename: Gerhard H
authors.initials: GH
authors.lastname: Simon
authors.forename: Yanjun
authors.initials: Y
authors.lastname: Fu
authors.forename: Kirill
authors.initials: K
authors.lastname: Berejnoi
authors.forename: Laure S
authors.initials: LS
authors.lastname: Fournier
authors.forename: Vincenzo
authors.initials: V
authors.lastname: Lucidi
authors.forename: Benjamin
authors.initials: B
authors.lastname: Yeh
authors.forename: David M
authors.initials: DM
authors.lastname: Shames
authors.forename: Robert C
authors.initials: RC
authors.lastname: Brasch
mesh_terms: D000818:Animals; D003287:Contrast Media / Q000138:chemical synthesis / Q000493:pharmacokinetics; D050091:Dendrimers / Q000138:chemical synthesis / Q000493:pharmacokinetics; D005260:Female; D007472:Iohexol; D046911:Macromolecular Substances; D008325:Mammary Neoplasms, Experimental / Q000000981:diagnostic imaging*; D015394:Molecular Structure; D011092:Polyethylene Glycols / Q000138:chemical synthesis / Q000493:pharmacokinetics; D051381:Rats; D017207:Rats, Sprague-Dawley; D014057:Tomography, X-Ray Computed
chemical_list: D003287:Contrast Media; D050091:Dendrimers; D046911:Macromolecular Substances; C507127:PEG12000-Gen4-triiodo; D011092:Polyethylene Glycols; D007472:Iohexol