Search results for "Contrast media"

Hyperpolarized 3helium gas as a novel contrast agent for functional MRI of ventilation.

2002

The use of inhaled hyperpolarized 3He gas in MRI is a recent approach for ventilation imaging. It has recently received enormous interest since it is capable of producing new and regional information on normal and abnormal lung ventilation. Promising preclinical and preliminary clinical results are the driving force to start phase II trials with patients suffering from obstructive and restrictive lung diseases.

A top-down synthesis route to ultrasmall multifunctional Gd-based Silica nanoparticles for theranostic applications

2013

International audience; New, ultrasmall nanoparticles with sizes below 5 nm have been obtained. These small rigid platforms (SRP) are composed of a polysiloxane matrix with DOTAGA (1,4,7,10-tetraazacyclododecane-1-glutaric anhydride-4,7,10-triacetic acid)-Gd3+ chelates on their surface. They have been synthesised by an original top-down process: 1) formation of a gadolinium oxide Gd2O3 core, 2) encapsulation in a polysiloxane shell grafted with DOTAGA ligands, 3) dissolution of the gadolinium oxide core due to chelation of Gd3+ by DOTAGA ligands and 4) polysiloxane fragmentation. These nanoparticles have been fully characterised using photon correlation spectroscopy (PCS), transmission elec…

Self-assembly and alterable relaxivity of an organic cation-encapsulated gadolinium-containing polyoxometalate

2012

A new amphiphilic molecule bearing poly(ethylene oxide) (PEO) and quaternary ammonium group, was designed and synthesized to encapsulate paramagnetic Gd(III)-containing polyoxometalate (Gd-POM) through electrostatic interaction for obtaining a water-soluble organic-inorganic hybrid building block based on POM. The yielding organic cation-encapsulated Gd-POM (OCEP-Gd) complex exhibited water-solubility and amphiphility, leading to the spontaneous self-assembly into a regular vesicular structure with PEO chains towards water phase and POM units locating at the middle. The vesicular aggregate which has a regular monolayer structure, was further studied by means of dynamic light scattering, tra…

IMAGING IN RISONANZA MAGNETICA NELLE FISTOLE PERIANALI

2018

Prevalence and prognostic impact of nonischemic late gadolinium enhancement in stress cardiac magnetic resonance

2020

Aim To assess the prevalence and prognostic significance of NI-LGE in patients undergoing stress-CMR. Methods Stress-CMR with either dipyridamole or adenosine was performed in 283 patients (228 men, 81%) including perfusion imaging, wall motion evaluation and LGE. Follow-up was completed in all enrolled patients (median time: 1850 days; interquartile range: 1225-2705 days). Composite endpoint included cardiac death, ventricular tachycardia, myocardial infarction, stroke, hospitalization for cardiac cause and coronary revascularization performed beyond 90 days from stress-CMR scans. Results One hundred and twelve patients (40%) had negative LGE (no-LGE), 140 patients (49%) I-LGE and 31 patie…

Dynamic contrast-enhanced MRI parameters as biomarkers for the effect of vatalanib in patients with non-small-cell lung cancer.

2014

ABSTRACT:  Aims: To assess the utility of dynamic contrast-enhanced MRI parameters in the demonstration of early antiangiogenic effects and as prognostic biomarkers in second-line treatment of advanced-stage non-small-cell lung cancer with vatalanib. Patients & methods: The transfer constant (Ktrans) and the initial area under the contrast concentration–time curve at 60 s (AUC60) were assessed in 46 patients. Changes were compared with response evaluation from computed tomography imaging and Response Evaluation Criteria In Solid Tumors guidelines. Results: Statistically significant mean reductions in Ktrans (38.4%; p < 0.0001) and AUC60 (24.9%; p < 0.0001) were found at day 2. Af…

Multi-Slice CT (MSCT) in Cardiac Function Imaging: Threshold-Value-Supported 3D Volume Reconstructions to Determine the Left Ventricular Ejection Fra…

2002

Gene therapy with iNOS enhances regional contractility and reduces delayed contrast enhancement in a model of postischemic congestive heart failure

2012

Aims: The purpose of this study was to evaluate the effect of transient local myocardial gene transfer of iNOS on cardiac function in a large mammal animal model of heart failure induced by chronic ischemia. Methods: Chronic myocardial ischemia was induced using a minimally invasive model in 16 landrace pigs. Upon demonstration of heart failure, eight animals were treated with liposome-mediated iNOS-gene-transfer by local intramyocardial injection; eight animals received a sham procedure to serve as control. Results: The transmurality of late enhancement (control: 46.4%, iNOS: 35.9%; p < 0.05) was significantly decreased in the ischemic area in the iNOS-treated group. Wall thickness at end-…

Minimally Invasive Monitoring of Chronic Central Venous Catheter Patency in Mice Using Digital Subtraction Angiography (DSA)

2015

PLoS ONE 10(6), e0130661 (2015). doi:10.1371/journal.pone.0130661

Effects of MRI Contrast Agents on the Stem Cell Phenotype

2010

The ultimate therapy for ischemic stroke is restoration of blood supply in the ischemic region and regeneration of lost neural cells. This might be achieved by transplanting cells that differentiate into vascular or neuronal cell types, or secrete trophic factors that enhance self-renewal, recruitment, long-term survival and functional integration of endogenous stem/progenitor cells. Experimental stroke models have been developed to determine potential beneficial effect of stem/progenitor cell based therapies. To follow the fate of grafted cells in vivo, a number of non-invasive imaging approaches have been developed. Magnetic Resonance Imaging (MRI) is a high resolution, clinically relevan…