SYSTEMS AND METHODS FOR ASSESSING GAS TRANSFER IN LUNG USING MPT WITH A HYPERPOLARIZED 129Xe

摘要

1. The method of providing MRI data on gas exchange in the lungs and / or the status of the alveolar-capillary barrier, containing! transmission of an imaging sequence of RF MRI excitation pulses configured to excite a hyperpolarized 129Xe dissolved phase in a gas exchange region of a subject; and! generating a three-dimensional MRI image of a 129Xe gas-blood lung barrier using signal reconstruction data of a dissolved phase MRI image of 129Xe associated with both the red blood cell compartment (RBC) and the barrier compartment,! wherein the imaging sequence of the RF excitation pulses comprises a 3D spin echo imaging sequence whereby the 3D spin echo sequence generates an echo with an approximately 90 degree phase difference between the signals of the RBC compartment and the barrier compartment. ! 2. The method according to claim 1, in which the 180 degree refocusing RF pulse is timed early enough and the readout gradient is delayed sufficiently to generate a 90 degree phase difference between the RBC and barrier compartments in the center of the k-space. ! 3. The method according to claim 1, in which the stages of transmission and generation are performed using the collection and reconstruction of data with a coarse sampling step. ! 4. The method according to claim 1, wherein the step of generating data comprises! obtaining a gaseous phase 129Xe MRI image for the patient; ! electronically generating a field map of the shifts of a spatially changing field, corresponding to the magnetic field inhomogeneity associated with the MRI scanner, based on the obtained 129Xe gaseous phase; and! electronic phase correction