Abstract #2582

Image Contrast Enhancement Using Selective Adiabatic Pulses That Alternate Frequency Sweep Directions

Ziqi Sun¹, Robert Bartha^2,3, Hanna A. Park¹, Surya Gnyawali¹

¹Davis Heart and Lung Research Institute, The Ohio State University, Columbus, OH, USA; ²Imaging Research Laboratories, Roberts Research Institute, London, Ontario, Canada; ³Departments of Diagnostic Radiology and Medical Biophysics, University of Western Ontario, London, Ontario, Canada

Image contrast enhancements were observed both in a multi-compartments phantom and in a stroke mouse model using a customized spin echo (SE) pulse sequence incorporated with selective adiabatic full passage (AFP) pulse trains that alternate frequency sweep (AFS) directions between adjacent pulses. Bloch equation simulation indicated that paired AFP-AFS pulse trains generated more accurate spin refocusing and thus signal intensity (SI) than that of the paired AFP pulses using single frequency sweep (SFS) in the pulse train. The accumulated nonlinear phase dispersion produced by the AFP-AFS pulse train also contributed to the contrast enhancement at longer TE.