title: Micro-CT based experimental liver imaging using a nanoparticulate contrast agent: a longitudinal study in mice.
abstract: BACKGROUND
  Micro-CT imaging of liver disease in mice relies on high soft tissue contrast to detect small lesions like liver metastases. Purpose of this study was to characterize the localization and time course of contrast enhancement of a nanoparticular alkaline earth metal-based contrast agent (VISCOVER ExiTron nano) developed for small animal liver CT imaging.
  
  
  METHODS
  ExiTron nano 6000 and ExiTron nano 12000, formulated for liver/spleen imaging and angiography, respectively, were intravenously injected in C57BL/6J-mice. The distribution and time course of contrast enhancement were analysed by repeated micro-CT up to 6 months. Finally, mice developing liver metastases after intrasplenic injection of colon carcinoma cells underwent longitudinal micro-CT imaging after a single injection of ExiTron nano.
  
  
  RESULTS
  After a single injection of ExiTron nano the contrast of liver and spleen peaked after 4-8 hours, lasted up to several months and was tolerated well by all mice. In addition, strong contrast enhancement of abdominal and mediastinal lymph nodes and the adrenal glands was observed. Within the first two hours after injection, particularly ExiTron nano 12000 provided pronounced contrast for imaging of vascular structures. ExiTron nano facilitated detection of liver metastases and provided sufficient contrast for longitudinal observation of tumor development over weeks.
  
  
  CONCLUSIONS
  The nanoparticulate contrast agents ExiTron nano 6000 and 12000 provide strong contrast of the liver, spleen, lymph nodes and adrenal glands up to weeks, hereby allowing longitudinal monitoring of pathological processes of these organs in small animals, with ExiTron nano 12000 being particularly optimized for angiography due to its very high initial vessel contrast.
authors: Department of Neuroradiology, Medical Faculty Mannheim, University of Heidelberg, Mannheim, Germany.
authors: Hanne
authors: H
authors: Boll
authors: Stefanie
authors: S
authors: Nittka
authors: Fabian
authors: F
authors: Doyon
authors: Michael
authors: M
authors: Neumaier
authors: Alexander
authors: A
authors: Marx
authors: Martin
authors: M
authors: Kramer
authors: Christoph
authors: C
authors: Groden
authors: Marc A
authors: MA
authors: Brockmann
mesh_terms: D000818:Animals; D003110:Colonic Neoplasms / Q000150:complications; D003287:Contrast Media / Q000737:chemistry*; D008099:Liver / Q000378:metabolism / Q000473:pathology*; D008113:Liver Neoplasms / Q000556:secondary; D051379:Mice; D053758:Nanoparticles; D055114:X-Ray Microtomography / Q000379:methods*
chemical_list: D003287:Contrast Media