Continued support is requested for a narrow and focussed program of development and application of surface and local radiofrequency coils for magnetic resonance imaging at 1.5 and 0.5 T and spectroscopy at 1.5 T. The proposal is addressed (a) to improved coil technology, (b) to development of novel imaging and spectroscopy strategies that depend on the special properties of surface coils, and (c) to clinical studies that make use of the improved technology. Improved coils can be achieved by attention to many small technical details in order to arrive at the highest possible free space Q. This is of particular importance in most coil configurations at 0.5 T and for small coils at 1.5 T. One can also improve image quality by tailoring the coils to the anatomic region of interest. But probably the most significant opportunity for improvement of coil performance is based on use of coil arrays. The idea rests on the basic theorem discovered in the previous funding period that there can be no correlation of noise in simultaneously acquired images of the same object if the mutual inductances between members of the coil array are negligible. A special case of this theorem is the quadrature detection surface coil, which is proposed in numerous variations including 31P spectroscopy. Three developments are proposed here that depend on special properties of surface coils: the spatial variation of vector reception field phase differences between two coils can aid spatial 31P localization and is the underlying property for a new method proposed here for making blood-flow velocity maps. In another development, fat suppressed and water suppressed images of small anatomic parts can be obtained with enhanced quality in 4 cm x 4 cm 256 x 256 images. Clinical imaging studies proposed here in detail are based on very high resolution technological advances recently achieved and uniquely available to us and include patients (a) with primary tumors of the skin, (b) with carpal tunnel syndrome, (c) with prostate carcinoma, (d) with cervical carcinoma, and (e) with lateral epicondylitis (tennis elbow). In future years, as the technology proposed here becomes available, clinical studies will be redirected to improved imaging of deep anatomic regions. A consortium is proposed with Duke University, T. M. Grist, P.I., to continue development and applications of surface coils for 31P spectroscopy. Grist is the P.I.'s former student. Of particular technological thrust is development of doubly tuned 31P quadrature detection surface coils, in some cases inserted into special whole volume coils for uniform presaturation. Applications focus on tissue grafts and possible rejection including kidneys, heart and skin.
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