Myocardial T1 During Multiple Bolus Injections
نویسندگان
چکیده
Introduction MR first pass perfusion imaging has become a valuable clinical tool for the assessment of myocardial perfusion [1]. The increased spin-lattice relaxation rate 1/T1 and dynamic signal enhancement following the intravenous injection of Gd-DTPA was shown [2] to be a linear function of the local gadolinium concentration. However, studies in rat myocardium [3] revealed that the enhancement may reach a plateau, which would inhibit the deduction of reliable kinetics from observed signal intensity-time curves. The aim of the present study was to investigate whether such a saturation effect has to be taken into account in MR-based perfusion studies involving multiple injections of Gd-DTPA. The myocardial T1 values were measured at multiple points in time during the study and compared with a reference, i.e. the expected T1 extrapolated from the previously published [4] washout kinetic tables of Gd-DTPA following a single injection.
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