Method and apparatus for gate specific MR-based attenuation correction of time-gated PET studies

An apparatus for generating a plurality of attenuation corrected time-gated PET images, said apparatus comprising:

• a PET-MR scanner;
• a controller connected in communication with the PET-MR scanner, wherein the controller is configured to acquire a baseline MR image of a structure, acquire a sequence of cine MR images of the structure, and acquire a plurality of time-gated PET data sets of the structure;
• and
• an image processor connected in communication with the controller, wherein the image processor is configured to generate a baseline ACF matrix based on the baseline MR image, register the baseline MR image with at least some of the cine MR images, generate cine ACF matrices based on registration of the baseline MR image with the cine MR images, and attenuation correct the time-gated PET data sets based on the cine ACF matrices.

A method for attenuation correction of PET imaging in a respiratory-gated PET study, comprising:

• obtaining, in a first MR acquisition, a baseline MR image suitable for deriving PET attenuation correction factors;
• obtaining, in a second MR acquisition, a cine sequence of MR images during a respiratory cycle, concurrent with the respiratory-gated PET study;
• and
• non-rigidly registering the baseline MR image to each of the cine MR images in order to produce a group of registered MR images that correspond to PET data sets from the respiratory-gated PET study and that are usable for deriving attenuation correction factors,
• wherein the registered MR images then are used to form attenuation correction factors for their respective time-gated PET data sets.