Investigative radiology
-
Investigative radiology · Oct 2011
Free-breathing quantitative dynamic contrast-enhanced magnetic resonance imaging in a rat liver tumor model using dynamic radial T(1) mapping.
: The high sensitivity to motion artifacts is a major limiting factor for applying the dynamic 3D T1-weighted gradient-echo (3D T1w GRE) technique for dynamic contrast-enhanced (DCE) magnetic resonance imaging (MRI) experiments in small rodents. Dynamic quantification of the relaxation rate R1 (1/T1) presents an alternative approach to reduce these motion artifacts. In this work, an optimized 2D single-shot Look-Locker based T1 mapping technique, named GOLD, applying radial sampling in the golden-angle view order and contrast-enhancing k-space filter was evaluated for its use in free-breathing quantitative DCE-MRI of rat liver on a clinical 1.5 T MRI system. ⋯ : The GOLD technique allowed dynamic sampling of 2D axial T1 maps of the rat abdomen with 6-second temporal resolution enabling simultaneous and robust pharmacokinetic modeling of HCC, normal liver, and spinal muscle.
-
Investigative radiology · Sep 2011
Comparative StudyPharmacokinetics and imaging properties of Gd-EOB-DTPA in patients with hepatic and renal impairment.
: The purpose of this study was to determine the pharmacokinetics (PKs), imaging properties, and safety of the liver-specific magnetic resonance (MR) imaging contrast agent gadoxetic acid disodium (Gd-EOB-DTPA) in subjects with various levels of hepatic impairment, renal impairment, or coexisting hepatic and renal impairment. ⋯ : The results of the present study show that in humans with moderate renal impairment and mild-to-moderate hepatic impairment, no relevant changes in PK parameters, such as total clearance and t1/2, develop as a result of increased renal excretion to compensate in the case of hepatic impairment (or increased hepatic elimination in the case of renal impairment). The t1/2 of Gd-EOB-DTPA was markedly altered only in patients with ESRF. The high MR signal enhancement profile, observed even in patients with severe hepatic impairment, indicates that there is no need to adjust the dose of Gd-EOB-DTPA.
-
Investigative radiology · Sep 2011
Comparative StudyGadoxetate disodium-enhanced magnetic resonance imaging versus contrast-enhanced 18F-fluorodeoxyglucose positron emission tomography/computed tomography for the detection of colorectal liver metastases.
: To compare the diagnostic accuracy of gadoxetate disodium-enhanced magnetic resonance imaging (EOB-MRI) on a 3-T system and integrated contrast-enhanced F-fluorodeoxyglucose positron emission tomography/computed tomography (CE-PET/CT) for the detection of hepatic metastases from colorectal cancers. ⋯ : EOB-MRI using a 3-T system is more accurate than CE-PET/CT, especially for the detection of small (≤1.0 cm) lesions. Patient-based analysis revealed that EOB-MRI has a higher sensitivity and negative predictive value than CE-PET/CT.
-
Investigative radiology · Aug 2011
Immediate intramyocardial bone marrow-derived mononuclear cells implantation in minipig myocardium after permanent coronary artery ligation: magnetic resonance imaging with histopathologic and immunochemical correlation.
: To investigate the effects of immediate intramyocardial implantation of autologous bone marrow-derived mononuclear cells (BMDMNCs) in minipig myocardium after coronary artery ligation with magnetic resonance imaging (MRI), histopathologic, and immunochemical studies. ⋯ : After myocardial infarction in a swine model, immediate intramyocardial BMDMNCs implantation may promote neovascularization with resultant improvement in LV function, perfusion, and myocardial viability as demonstrated on cardiovascular MRI.
-
Investigative radiology · Jul 2011
Randomized Controlled Trial Multicenter Study Comparative StudyMagnetic resonance evaluation of brain metastases from systemic malignances with two doses of gadobutrol 1.0 m compared with gadoteridol: a multicenter, phase ii/iii study in patients with known or suspected brain metastases.
To determine the efficacy and safety of 2 doses of gadobutrol 1.0 M (0.1 and 0.2 mmol/kg body weight [BW]), compared with gadoteridol 0.5 M (0.2 mmol/kg BW), in contrast-enhanced magnetic resonance imaging (CE-MRI) of brain metastases in patients with known or suspected brain metastases from systemic malignancies. The study also compared the usefulness of gadobutrol in treatment planning for stereotactic radiosurgery (SRS). ⋯ In this study, a single dose of gadobutrol was shown to be noninferior to a double dose of gadoteridol at detecting brain metastases, and could be effectively used for treatment planning in patients eligible for SRS. A dose of gadobutrol 0.1 mmol/kg BW is recommended as the clinical dose for the detection of brain metastases.