title: Inversion-recovery-prepared SSFP for cardiac-phase-resolved delayed-enhancement MRI.
abstract: Delayed-enhancement magnetic resonance imaging (DE-MRI) can be used to visualize myocardial infarction (MI). DE-MRI is conventionally acquired with an inversion-recovery gradient-echo (IR-GRE) pulse sequence that yields a single bright-blood image. IR-GRE imaging requires an accurate estimate of the inversion time (TI) to null the signal from the myocardium, and a separate cine acquisition is required to visualize myocardial wall motion. Simulations were performed to examine the effects of a steady-state free precession (SSFP) readout after an inversion pulse in the setting of DE-MRI. Using these simulations, a segmented IR-SSFP sequence was optimized for infarct visualization. This sequence yields both viability and wall motion images over the cardiac cycle in a single breath-hold. Viability images at multiple effective TIs are produced, providing a range of image contrasts. In a study of 11 patients, IR-SSFP yielded infarct sizes and left ventricular ejection fractions (LVEFs) similar to those obtained by IR-GRE and standard SSFP, respectively. IR-SSFP images yielded improved visualization of the infarct-blood border because of the simultaneous nulling of healthy myocardium and blood. T(1) (*) recovery curves were extracted from IR-SSFP images and showed excellent qualitative agreement with theoretical simulations.
authors.affiliation: Department of Imaging Research, Sunnybrook Health Sciences Centre, Toronto, Ontario, Canada. jay.detsky@sri.utoronto.ca
authors.forename: J S
authors.initials: JS
authors.lastname: Detsky
authors.forename: J A
authors.initials: JA
authors.lastname: Stainsby
authors.forename: R
authors.initials: R
authors.lastname: Vijayaraghavan
authors.forename: J J
authors.initials: JJ
authors.lastname: Graham
authors.forename: A J
authors.initials: AJ
authors.lastname: Dick
authors.forename: G A
authors.initials: GA
authors.lastname: Wright
mesh_terms: D003198:Computer Simulation; D003287:Contrast Media; D005260:Female; D019786:Gadolinium DTPA; D006801:Humans; D007091:Image Processing, Computer-Assisted; D019028:Magnetic Resonance Imaging, Cine / Q000379:methods*; D008297:Male; D008875:Middle Aged; D009203:Myocardial Infarction / Q000175:diagnosis*
chemical_list: D003287:Contrast Media; D019786:Gadolinium DTPA