title: An investigation of the toxicity of gadolinium based MRI contrast agents using neutron activation analysis.
abstract: The toxicity of gadolinium (Gd) based MRI contrast agents, is based upon the amount of Gd that dissociates from its chelate and deposits in tissues. In this study, the toxicities of two contrast agents were tested using different injection strategies in two animal models. Following a bolus injection of 0.2 mmol/kg of Gd-DTPA in a pilot study with a single canine, Gd levels were as high as 2.05 +/- 0.17 ppm and 0.47 +/- 0.11 ppm 2 weeks post injection in the kidney and liver tissues, respectively. To evaluate the role that the injection strategy plays in toxicity, 0.8 mmol/kg of Gd-(HP-DO3A) was injected into rats, in a second study, via bolus and constant infusion techniques. Gd was only detected in the kidney in the bolus injected rats but in the lung as well in the constant infusion injected rats. Concentrations detected in the kidney for both strategies, were comparable within error: 1.37 +/- 0.46 ppm for the bolus and 1.24 +/- 0.39 ppm for the bolus/constant infusion strategy and 0.16 +/- 0.14 ppm in the lung for the constant infusion technique. The contrast infusion technique does not appear to present an increased risk of toxicity over the bolus technique except perhaps to a small degree in the lung.
authors.affiliation: Department of Medical Physics and Applied Radiation Sciences, McMaster University, Hamilton, Ontario, Canada.
authors.forename: M E
authors.initials: ME
authors.lastname: Bartolini
authors.forename: J
authors.initials: J
authors.lastname: Pekar
authors.forename: D R
authors.initials: DR
authors.lastname: Chettle
authors.forename: F
authors.initials: F
authors.lastname: McNeill
authors.forename: A
authors.initials: A
authors.lastname: Scott
authors.forename: J
authors.initials: J
authors.lastname: Sykes
authors.forename: F S
authors.initials: FS
authors.lastname: Prato
authors.forename: G R
authors.initials: GR
authors.lastname: Moran
mesh_terms: D000818:Animals; D003287:Contrast Media / Q000008:administration & dosage / Q000633:toxicity*; D004285:Dogs; D005682:Gadolinium; D019786:Gadolinium DTPA / Q000008:administration & dosage / Q000633:toxicity*; D006571:Heterocyclic Compounds / Q000008:administration & dosage / Q000633:toxicity*; D007262:Infusions, Intravenous; D007275:Injections, Intravenous; D008279:Magnetic Resonance Imaging; D009501:Neutron Activation Analysis; D009942:Organometallic Compounds / Q000008:administration & dosage / Q000633:toxicity*; D051381:Rats
chemical_list: D003287:Contrast Media; D006571:Heterocyclic Compounds; D009942:Organometallic Compounds; C062402:gadoteridol; D005682:Gadolinium; D019786:Gadolinium DTPA