title: A liposomal nanoscale contrast agent for preclinical CT in mice.
abstract: OBJECTIVE
  The goal of this study was to determine if an iodinated, liposomal contrast agent could be used for high-resolution, micro-CT of low-contrast, small-size vessels in a murine model.
  
  
  METHODS
  A second-generation, liposomal blood pool contrast agent encapsulating a high concentration of iodine (83-105 mg I/mL) was evaluated. A total of five mice weighing between 20 and 28 g were infused with equivalent volume doses (500 microL of contrast agent/25 g of mouse weight) and imaged with our micro-CT system for intervals of up to 240 min postinfusion. The animals were anesthetized, mechanically ventilated, and vital signs monitored allowing for simultaneous cardiac and respiratory gating of image acquisition.
  
  
  RESULTS
  Initial enhancement of about 900 H in the aorta was obtained, which decreased to a plateau level of approximately 800 H after 2 hr. Excellent contrast discrimination was shown between the myocardium and cardiac blood pool (650-700 H). No significant nephrogram was identified, indicating the absence of renal clearance of the agent.
  
  
  CONCLUSIONS
  The liposomal-based iodinated contrast agent shows long residence time in the blood pool, very high attenuation within submillimeter vessels, and no significant renal clearance rendering it an effective contrast agent for murine vascular imaging using a micro-CT scanner.
authors.affiliation: Department of Radiology, Duke University Medical Center, Box 3808, Durham, NC 27705, USA.
authors.forename: Srinivasan
authors.initials: S
authors.lastname: Mukundan
authors.forename: Ketan B
authors.initials: KB
authors.lastname: Ghaghada
authors.forename: Cristian T
authors.initials: CT
authors.lastname: Badea
authors.forename: Chen-Yu
authors.initials: CY
authors.lastname: Kao
authors.forename: Laurence W
authors.initials: LW
authors.lastname: Hedlund
authors.forename: James M
authors.initials: JM
authors.lastname: Provenzale
authors.forename: G Allan
authors.initials: GA
authors.lastname: Johnson
authors.forename: Emmanuel
authors.initials: E
authors.lastname: Chen
authors.forename: Ravi V
authors.initials: RV
authors.lastname: Bellamkonda
authors.forename: Ananth
authors.initials: A
authors.lastname: Annapragada
mesh_terms: D000818:Animals; D003287:Contrast Media / Q000737:chemistry / Q000493:pharmacokinetics*; D007091:Image Processing, Computer-Assisted; D008081:Liposomes; D051379:Mice; D013902:Radiography, Thoracic; D014057:Tomography, X-Ray Computed; D014283:Triiodobenzoic Acids / Q000737:chemistry / Q000493:pharmacokinetics*
chemical_list: D003287:Contrast Media; D008081:Liposomes; D014283:Triiodobenzoic Acids; C044834:iodixanol