Positive contrast with therapeutic iron nanoparticles at 4.7T
- نوع فایل : کتاب
- زبان : انگلیسی
- مؤلف : Monica Sigovan · Misara Hamoudeh · Achraf Al Faraj · Delphine Charpigny · Hatem Fessi · Emmanuelle Canet-Soulas
- چاپ و سال / کشور: 2011
Description
Object The purpose of the study was to show the feasibility of a positive contrast technique GRadient echo Acquisition for Superparamagnetic particles with Positive contrast (GRASP), for a specific type of magnetic particles, designed for tumor treatment under MRI monitoring. Materials and methods Asimulation studywas performed to estimate field inhomogeneity intensities induced by increasing concentrations of particles at different static fields. The GRASP sequence was setup on a 4.7T Bruker system during an in vitro study. Six mice, included in the in vivo study received particles in the left calf muscle and contrast enhancement values, were measured over three time points, for both negative and positive contrast images. Results Comparing values obtained by simulation at 1.5, 3, and 4.7T, the strongest susceptibility effect was obtained at 4.7 T. Based on simulation and in vitro data, gradient settings were chosen for in vivo imaging. GRASP resulted in bright regions at and around the injection site, and higher enhancement values, compared to standard GRE imaging. Both contrasts were useful for longitudinal follow-up, with a faster decay over time for GRASP. Conclusion The magnetic nanoparticles for drug delivery can be detected using positive contrast. Combining imaging sequences, i.e., negative contrast and susceptibility methods, increased imaging specificity of large magnetic particles and enabled their follow-up for theranostic applications.
Magn Reson Mater Phy DOI 10.1007/s10334-011-0258-7 Received: 26 October 2010 / Revised: 13 April 2011 / Accepted: 6 May 2011
