Accelerated echo planar J-resolved spectroscopic imaging in XXXX : a pilot validation of non-linear reconstruction using total variation and maximum entropy.

@entity1 @entity263 @entity8580 @entity3264 @entity5 @entity908 @entity8037 @entity7748 @entity3736 @entity1877
UNASSIGNED: The overlap of metabolites is a major limitation in one-dimensional (1D) spectral-based single-voxel @entity7748 and multivoxel-based MRSI. By combining echo planar spectroscopic imaging (EPSI) with a two-dimensional (2D) J-resolved spectroscopic (JPRESS) sequence, 2D spectra can be recorded in multiple locations in a single slice of prostate using four-dimensional (4D) echo planar J-resolved spectroscopic imaging (EP-JRESI). The goal of the present work was to validate two different non-linear reconstruction methods independently using compressed sensing-based 4D EP-JRESI in @entity263 ( @entity263 ): maximum entropy (MaxEnt) and total variation (TV). Twenty-two @entity1 with @entity263 with a mean age of 63.8 years (range, 46-79 years) were investigated in this study. A 4D non-uniformly undersampled (NUS) EP-JRESI sequence was implemented on a Siemens 3-T MRI scanner. The NUS data were reconstructed using two non-linear reconstruction methods, namely MaxEnt and TV. Using both TV and MaxEnt reconstruction methods, the following observations were made in @entity5 compared with non- @entity5 locations: (i) higher mean ( @entity1877 + @entity908 )/ @entity3736 metabolite ratios; (ii) increased levels of ( @entity1877 + @entity908 )/ @entity8037 and ( @entity1877 + @entity908 )/ @entity8580 ; and (iii) decreased levels of ( @entity1877 + @entity908 )/( @entity3264 + @entity3264 ). We have shown that it is possible to accelerate the 4D EP-JRESI sequence by four times and that the data can be reliably reconstructed using the TV and MaxEnt methods. The total acquisition duration was less than 13 min and we were able to detect and quantify several metabolites. Copyright    2015 John Wiley _ Sons, Ltd.
