An adiabatic multiple spin-echo pulse sequence: Removal of systematic errors due to pulse imperfections and off-resonance effects

Application of AFP (adiabatic fast passage) pulses for removal of systematic errors associated with multiple spin-echo sequences is demonstrated. The adiabatic fast passage pulses facilitate minimization of cumulative pulse errors for all three components of magnetization. It is also shown that off-resonance effects present in conventional CPMG sequences which degrade image quality in magnetic resonance imaging and introduce systematic errors in measured T-2 relaxation time peak amplitudes can be suppressed by introduction of AFP pulses without any degradation of overall signal intensity. The technique has been tested on the N-15 spin-spin relaxation time measurements of a 110 amino acid domain of the F-actin cross-linking protein. (C) 1998 Academic Press.