In Vivo and ex vivo High Resolution slow-MAS MR Spectroscopy in Mice
EMSL Project ID
16108
Abstract
The overall goal of this project is to develop a methodology to increase the resolution of magnetic resonance (MR) metabolite spectra in excised tissues and live mice. Although MR spectroscopy is increasingly used for biochemical and medical studies, the spectra often suffer from poor resolution, which diminishes seriously their utility. In previous work we have shown that it is possible to increase the spectral resolution significantly by applying so-called phase-adjusted spinning sidebands (PASS) and phase-corrected magic angle turning (PHORMAT) techniques, where a slow rotation of the sample around an axis making an angle of 54o44’ relative to the external magnetic field is combined with special RF pulse sequences. With PHORMAT spinning speeds as low as 1 Hz could be employed, which makes it possible to use this technique to study large intact tissues and even live animals. In this application the viability of PASS and PHORMAT approach for ex vivo and in vivo applications will be further evaluated. To this end the necessary instrumentation will be developed integrating PASS and PHORMAT with MR imaging, volume-selective PASS and PHORMAT will be developed, the PHORMAT technique will be improved to increase its MR sensitivity and reduce its measuring time, and 1H PHORMAT experiments will be carried out on different organs and tissues of live mice. The results will be used to determine the impact of motions in the animal on the spectral resolution, to investigate the quantitative character of the spectra, to evaluate the possibilities of the PHORMAT approach in high magnetic fields, and to evaluate the feasibility of PHORMAT using other magnetic nuclei than protons. In addition quantitative localized PASS experiments will be carried out in various excised tissues in different fields.Ultimately the project might provide a new unique capability for in vivo MR spectroscopy research in animals that will make it possible to analyze MR metabolite spectra in considerably more detail than could be done previously. This would significantly increase the utility of MR spectroscopy for biomedical research, diagnosis, and therapy evaluation in live animals. In fact, the technique may even become useful for examining patients in the clinic, in this case by rotating the magnetic field rather than the patient.
Project Details
Project type
Capability Research
Start Date
2005-10-01
End Date
2007-03-20
Status
Closed
Released Data Link
Team
Principal Investigator