Spectral localization by imaging using multielement receiver coils.

A new spectral localization technique for in vivo magnetic resonance spectroscopy is introduced. Structural information extracted from anatomical imaging is used for defining compartments which provide the basis for spectral localization. The inherent spatial heterogeneity of multiple receiver coil elements is used along with optional phase encoding to resolve signals from different compartments. This technique allows a few compartmental spectra to be reconstructed from multichannel data acquired with no or very few phase encoding steps, resulting in short scan time and high efficiency. Alternatively, this technique also allows a significant number of compartmental spectra to be reconstructed if sufficient phase encoding steps are used. A procedure is developed to semiautomatically generate a significant number of compartments of comparable sizes, which allows one to obtain spectra from small regions of interest with curvilinear shapes. This may be useful for obtaining spectra from relatively small stroke lesions or tumors. Phantom experiments and in vivo magnetic resonance spectroscopy of stroke patients have been performed to demonstrate this technique.