Abstract: An image reconstruction method includes reconstructing an initial composite image of a subject using a conventional reconstruction method. The initial composite image employs the best information available regarding the subject of the scan and this information is used to constrain the reconstruction of a highly undersampled or low SNR image frames. This highly constrained image reconstruction is repeated a plurality of iterations with the reconstructed image frame for one iteration being used as the composite image for the next iteration. The reconstructed image frame rapidly converges to a final image frame.

Abstract: A method for measuring the apparent transverse relaxation time (“T*2”) and apparent diffusion coefficient (“ADC”) of a hyperpolarized gas in a single breath-hold and consequently, with a single dose of the hyperpolarized gas contrast agent, is provided. The method employs a multiple-echo projection acquisition based pulse sequence. Individual images are reconstructed from data acquired during each of the individual echo times. Subsequently, T*2 and ADC are calculated using these reconstructed images. Furthermore, the method produces images indicative of ADC that have isotropic resolution, allowing for more reliable image registration. The inter-echo spacing and diffusion weighting b-value are varied during the pulse sequence employed when practicing the present invention; thus, a significant separation between the effects of diffusion and T*2 decay on the detected MR signals is possible. This separation allows for reliable measurements of these two parameters from a single echo-train.

Abstract: A method for measuring the apparent transverse relaxation time (“T2*”) and apparent diffusion coefficient (“ADC”) of a hyperpolarized gas in a single breath-hold and consequently, with a single dose of the hyperpolarized gas contrast agent, is provided. The method employs a multiple-echo projection acquisition based pulse sequence. Individual images are reconstructed from data acquired during each of the individual echo times. Subsequently, T2* and ADC are calculated using these reconstructed images. Furthermore, the method produces images indicative of ADC that have isotropic resolution, allowing for more reliable image registration. The inter-echo spacing and diffusion weighting b-value are varied during the pulse sequence employed when practicing the present invention; thus, a significant separation between the effects of diffusion and T2* decay on the detected MR signals is possible. This separation allows for reliable measurements of these two parameters from a single echo-train.

Abstract: An image reconstruction method includes reconstructing an initial composite image of a subject using a conventional reconstruction method. The initial composite image employs the best information available regarding the subject of the scan and this information is used to constrain the reconstruction of a highly undersampled or low SNR image frames. This highly constrained image reconstruction is repeated a plurality of iterations with the reconstructed image frame for one iteration being used as the composite image for the next iteration. The reconstructed image frame rapidly converges to a final image frame.