about abs and fastMRI data

[lz666win]

I check your code, you use abs between Data Consistency,but is there any information loss between abs? I mean MRI data always use complex value data to get phase information, and phase information is often used to diagnose intracranial hemorrhage and local overheating，when you use abs layer, the real-part is calculate the modulus and the image-part is zero, the phase information will loss. The second question is do you use the whole data of fastMRI or a part for training? Looking forward for your reply!

[tinyRattar]

Good question. I didn't know that phase information is also important for diagnose, so I can't answer the first question. I believe that the phase information will loss, but part of the information is generate from network, I mean, it is not exactly true. And even the last sub-network will be followed by an Data Consistency, if the phase information is important, maybe it is a good chance to recovery? Sorry, but I'm not sure about it, the meaning of phase information is hard to make sense for me. I will be thankful if u can tell me more about what diagnostics truly care about.

I just use the part of fastMRI for training, maybe the validation part I guess? Thank you

[JingshuaiLiu]

Thanks for the provided code.

May I ask if you have ever conducted the ablation study, i.e. remove the absolute-based DC, for FastMRI data, as it is applied to cardiac MR reconstruction? As presented in Figure 6 and 7, dual data consistency can improve the reconstruction quality and result in lower errors. However, the training samples are real-valued, namely in magnitude domain, and the inverse transform combined with an absolute operation might be able to harmonize the data correction when the second DC follows, like real data can be transformed with stacked imaginary part.

Considering that FastMRI provides complex-valued data, the question is that if DC in magnitude can still benefit reconstructions. If the answer is yes, these might be some functional mechanism in dual DC and it will be of greater interest.

Thanks a lot.