Patent ID: 11885863
Assignee: ASELSAN ELEKTRONIK SANAYI VE TICARET ANONIM SIRKETI
Field: Measurement (Instruments)
Classification: CPC G | IPC G

Claim 6:
7. A method for reconstructing images of a magnetic resonance imaging (MRI) system comprising the steps of;
acquiring with the MRI system, multiple images under an influence of different contrast mechanisms, wherein the different contrast mechanisms belong to a same anatomy,
solving an optimization problem with an optimization algorithm using both joint and individual objective functions simultaneously for each of multiple image contrasts or a subset of the multiple image contrasts, to reconstruct the multiple images from acquired data,

wherein the optimization problem solved with a synthesis based method is formulated as below with an approach considering a signal, a linear combination of basis atoms of a dictionary;, ⁢
    
      
        
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where Ai denotes a transformation matrix, wherein the transformation matrix maps samples of an image to the samples in a data domain, and the data domain comprises a Fourier domain, {circumflex over (x)}i denotes a reconstructed image, and yi denotes associated acquired data for each of the multiple image contrasts; CTV, GSp, TV, and Sp denote a Color Total Variation, a Group Sparsity (12-1-norm), an individual Total Variation and an individual Sparsity (11-norm), respectively, and the Color Total Variation, the Group Sparsity, the individual Total Variation and the individual Sparsity are defined as:

CTV(|x|)=Σn√{square root over (Σki=1k((∇1|x(i)[n]|)2+(∇2|x(i)[n]|)2),)}

∥x∥2,1=Σn√{square root over (Σi=1k|x(i)[n]|2)},

TV(|x(i)∥)=Σn√{square root over ((∇1|x(i)[n]|)2+(∇2|x(i)[n]|)2)},

∥x(i)∥1=Σn|x(i)[n]|.