The application of 3D chemical shift microscopy to noninvasive histochemistry.

Three-dimensional chemical shift imaging methods offer significant advantages over two-dimensional (chemical shift selective) techniques for the study of biological samples which exhibit complex spectra. We have applied 3D-CSI methods to the study of a plant system, (dried fennel mericarps) previously studied by 2D-CSI techniques, obtaining images with in-plane resolution down to 30 microns and special resolution of 0.4 ppm. A modification of the 3D-CSI technique which incorporates water suppression by a combination of pre-saturation and selective excitation is also described and its performance evaluated on both a phantom and a fresh fennel sample.