Quantitative dual-energy CT material decomposition of holmium microspheres: local concentration determination evaluated in phantoms and a rabbit tumor model.

Objectives: The purpose of this study was to assess the feasibility of dual-energy CT-based material decomposition using dual-X-ray spectra information to determine local concentrations of holmium microspheres in phantoms and in an animal model.

Materials And Methods: A spectral calibration phantom with a solution containing 10 mg/mL holmium and various tube settings was scanned using a third-generation dual-energy CT scanner to depict an energy-dependent and material-dependent enhancement vectors. A serial dilution of holmium (microspheres) was quantified by spectral material decomposition and compared with known holmium concentrations.

Nile Red Quantifier: a novel and quantitative tool to study lipid accumulation in patient-derived circulating monocytes using confocal microscopy.

The inflammatory profile of circulating monocytes is an important biomarker for atherosclerotic plaque vulnerability. Recent research revealed that peripheral lipid uptake by monocytes alters their phenotype toward an inflammatory state and this coincides with an increased lipid droplet (LD) content. Determination of lipid content of circulating monocytes is, however, not very well established.

Evaluation of ultrasmall superparamagnetic iron-oxide (USPIO) enhanced MRI with ferumoxytol to quantify arterial wall inflammation.

Background And Aims: Inflammation in atherosclerotic plaques is an important determinant of plaque vulnerability, and can be detected non-invasively using ultra-small superparamagnetic iron-oxide (USPIO) enhanced MRI. The aims of the current study were: 1) to determine whether ferumoxytol can be used for USPIO-MRI of atherosclerotic plaques, 2) to establish a protocol for quantitative USPIO-MRI of carotid artery plaques using ferumoxytol, and 3) to study the relation between USPIO uptake and plaque burden and F-fluorodeoxyglucose (FDG) uptake (measured by F-FDG PET/CT scan) in atherosclerotic plaques.

Methods: In 9 patients with carotid artery stenosis >30% and 4 healthy controls, quantitative R2* MRI scans of the carotid arteries were performed before and 72 h after USPIO administration (4 mg/kg ferumoxytol).