Parametric exploration of the liver by magnetic resonance methods

MRI, as a completely noninvasive technique, can provide quantitative assessment of perfusion, diffusion, viscoelasticity and metabolism, yielding diverse information about liver function. Furthermore, pathological accumulations of iron and lipids can be quantified. Perfusion MRI with various contrast agents is commonly used for the detection and characterization of focal liver disease and the quantification of blood flow parameters. An extended new application is the evaluation of the therapeutic effect of antiangiogenic drugs on liver tumours. Novel, but already widespread, is a histologically validated relaxometry method using five gradient echo sequences for quantifying liver iron content elevation, a measure of inflammation, liver disease and cancer. Because of the high perfusion fraction in the liver, the apparent diffusion coefficients strongly depend on the gradient factors used in diffusion-weighted MRI. While complicating analysis, this offers the opportunity to study perfusion without contrast injection. Another novel method, MR elastography, has already been established as the only technique able to stage fibrosis or diagnose mild disease. Liver fat content is accurately determined with multivoxel MR spectroscopy (MRS) or by faster MRI methods that are, despite their widespread use, prone to systematic error. Focal liver disease characterisation will be of great benefit once multivoxel methods with fat suppression are implemented in proton MRS, in particular on high-field MR systems providing gains in signal-to-noise ratio and spectral resolution

A core-shell nanomaterial with endogenous therapeutic and diagnostic functions

In the present communication, we report the fabrication of a unique core-shell inorganic nanomaterial with potential therapeutic and diagnostic functions. It contains an iron–cobalt (FeCo) core that demonstrates magnetic resonance imaging (MRI) contrast property and a thin nanoshell of gold that inhibits the function of a pro-angiogenic growth factor, VEGF165. Au(FeCo) core-shell nanomaterials are fabricated in the gas phase and characterized using transmission electron microscopy, energy dispersive spectrum, inductively coupled plasma analysis, and MRI. Inhibition of VEGF165 function by Au(FeCo) is demonstrated against VEGF165/VPF-induced signaling cascades and proliferation of human umbilical vein endothelial cells (HUVECs). The self-contrast property of Au(FeCo) is determined in vitro by MRI after incubating HUVECs with Au(FeCo), demonstrating intrinsic contrast property of this potentially therapeutic nanomaterial. In brief, we report here the successful fabrication of an inorganic core-shell nanomaterial with potential therapeutic and diagnostic functions. It inhibits the function of VEGF165 and functions as a MRI contrast agent

Technology Insight: advances in liver imaging

The role of diagnostic imaging in the assessment of liver disease continues to gain in importance. The classic techniques used for liver imaging are ultrasonography, CT and MRI. In the past decade, there have been significant advances in all three techniques. In this article, we discuss the advances in ultrasonography, CT and MRI that have improved assessment of focal and diffuse liver disease, including the development of hardware, software, processing algorithms and procedural innovations