DUAL SURFACE COIL WITH HIGH-B-1 HOMOGENEITY FOR DEEP ORGAN MR-IMAGING

The theory and construction of a dual surface coil which provides good B-1 homogeneity and sensitivity in a defined volume of interest is de scribed. The probe comprises two coaxial rings, of different diameters and in different planes, which carry opposing currents of different v alues. Current in the second ring compensates for the roll-off of the B-1 field associated with a single surface coil. Coupling between the rings and a third matching ring is by mutual inductance only. A compar ison to a traditional surface coil with practical application to pig b rain imaging at a field strength of 7 Tesla is shown. (C) 1997 Elsevie r Science Inc.