Dr. Friedrich Wetterling
Trinity College Dublin, Ireland
Abstract
Magnetic resonance imaging (MRI) is a
non-invasive technique which enables to spatially resolve
signals originating from hydrogen-1 nuclei. However, also other
MRI-active nuclei, e.g. sodium-23, phosphorus-31, carbon-13,
potassium-39, and chlorine-35 can be observed using MRI scanners
capable of broadband radio-frequency (rf) excitation. The mammal metabolism
involves many of these so called X-nuclei. Hence, MRI of these nuclei
may provide a useful method to study the human metabolism in
normal and pathological conditions non-invasively. So far, metabolic MRI has
been challenging due to the lack of sufficient signal
sensitivity resulting in poor spatial resolution by comparison
to standard hydrogen-1 MRI. In
this talk, pragmatic approaches to improve the
signal-to-noise-ratio per voxel size and acquisition time are
presented. For instance,
optimized rf detectors can help to drastically improve the
signal sensitivity and hence allow for the observation of
metabolic processes such as the swelling of cells in brain
tissue after arterial occlusion.
The ability to thus acquire whole-body sodium-23 MR
images of the human demonstrates that metabolic 3D scanning
methods are clinically practical. Hence, the diagnostic question
of whether tissue is partially dead or still alive at a given
point in time may be answered non-invasively in the future, e.g.
to inform treatment for stroke or tumor therapy patients.
