A T.sub.2 preparation sequence uses a segmented BIR-4 adiabatic pulse with
two substantially equal delays and is insensitive to B.sub.1 field
variations and can simultaneously suppress fat signals with low specific
absorption rate (SAR). An adiabatic reverse half passage pulse is applied
followed by a predetermined delay. An adiabatic full passage pulse is
applied followed by a substantially equal delay, followed by an adiabatic
half passage pulse. Fat signal suppression is achieved by increasing or
decreasing either the first delay or the second delay.