Nicolas Geades
Project Title: Improved sequences for generating new image contrasts
Supervisor: Penny Gowland
Centre: SPMMRC, Nottingham
Secondment: Utrecht and Philips
Project Description
The high sensitivity of UHF MR, coupled with increased RF power deposition, RF field inhomogeneity and changes in the intrinsic NMR properties of tissues, mean that MR pulse sequences must be redesigned for optimal data acquisition at UHF. Furthermore, novel sequences are required to exploit the new contrasts available at UHF. Sequences must be optimized for maximum sensitivity to the parameters of interest, minimal power deposition and minimal sensitivity to motion. Methods of modeling and fitting the data from the sequences must also be developed. At the spatial resolutions available at UHF subject motion becomes the factor limiting spatial resolution, therefore the motion-sensitivity of sequences must also be considered. Increased sensitivity to magnetization transfer (MT) at UHF allows high resolution MT mapping, for instance across the cortex. Chemical Exchange Saturation Transfer (CEST) provides a chemically specific image contrast, and increased sensitivity at UHF opens up the possibility of making practical CEST measurements in vivo. CEST has been most widely used to detect amide groups associated with myelin, but it is likely that CEST can also be made sensitive to a range of other chemical groups by changing the sequence parameters, and can be used to detect tailored contrast agents with high sensitivity. This project is focused on characterizing 7T z-spectra, specifically Amide Proton Transfer (APT), Nuclear Overhauser Effect (NOE) and MT peaks, and designing protocols for quantitative imaging of different MR parameters for in vivo clinical imaging
Outreach: Light Night 2014 (Nottingham)
Meetings Attended: Postgrad BCISMRM 2014, Joint Annual Meeting ISMRM/ESMRMB 2014 (Milan)
Publications:Measuring MT, NOE and CEST effects in human brain in vivo at 7T. N. Geades, O. Mougin and P. Gowland (2014). BC-ISMRM Poster
Contact: ppxng@exmail.nottingham.ac.uk
CV: