A NEW LOCALIZATION METHOD USING AN ADIABATIC PULSE, BIR-4

A new method is described for accomplishing localized spectroscopy wit h an adiabatic pulse, BIR-4. The method has advantages similar to prev iously described combinations of outer-volume suppression (OVS) and IS IS, with the additional advantages that localization is achieved with only three radiofrequency pulses and the localization remains accurate even in the presence of intense signals with short relaxation times. This new localization pulse sequence is referred to as integrated OVS- ISIS. Computer simulations, experimental images of the localized volum es, and in vivo H-1 spectroscopy measurements demonstrate the high deg ree of localization achievable with integrated OVS-ISIS. (C) 1995 Acad emic Press, Inc.