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<Articles JournalTitle="Frontiers in Biomedical Technologies">
  <Article>
    <Journal>
      <PublisherName>Tehran University of Medical Sciences</PublisherName>
      <JournalTitle>Frontiers in Biomedical Technologies</JournalTitle>
      <Issn>2345-5837</Issn>
      <Volume>7</Volume>
      <Issue>1</Issue>
      <PubDate PubStatus="epublish">
        <Year>2020</Year>
        <Month>03</Month>
        <Day>30</Day>
      </PubDate>
    </Journal>
    <title locale="en_US">Reconstruction of Simulated Magnetic Resonance Fingerprinting Using Accelerated Distance Metric Learning</title>
    <FirstPage>3</FirstPage>
    <LastPage>13</LastPage>
    <Language>EN</Language>
    <AuthorList>
      <Author>
        <FirstName>Elmira</FirstName>
        <LastName>Yazdani</LastName>
        <affiliation locale="en_US">Department of Medical Physics and Biomedical Engineering, Tehran University of Medical Sciences, Tehran, Iran</affiliation>
      </Author>
      <Author>
        <FirstName>Sajjad</FirstName>
        <LastName>Aghabozorgi Sahaf</LastName>
        <affiliation locale="en_US">Department of Energy Engineering, Sharif University of Technology, Tehran, Iran</affiliation>
      </Author>
      <Author>
        <FirstName>Hamidreza</FirstName>
        <LastName>Saligheh Rad</LastName>
        <affiliation locale="en_US">Department of Medical Physics and Biomedical Engineering, Tehran University of Medical Sciences, Tehran, Iran</affiliation>
      </Author>
    </AuthorList>
    <History>
      <PubDate PubStatus="received">
        <Year>2019</Year>
        <Month>11</Month>
        <Day>29</Day>
      </PubDate>
      <PubDate PubStatus="accepted">
        <Year>2020</Year>
        <Month>01</Month>
        <Day>16</Day>
      </PubDate>
    </History>
    <abstract locale="en_US">Purpose: Magnetic Resonance Fingerprinting (MRF) is a novel framework that uses a random acquisition to acquire a unique tissue response, or fingerprint. Through a pattern-matching algorithm, every voxel-vise fingerprint is matched with a pre-calculated dictionary of simulated fingerprints to obtain MR parameters of interest. Currently, a correlation algorithm performs the MRF matching, which is time-consuming. Moreover, MRF suffers from highly undersampled k-space data, thereby reconstructed images have aliasing artifact, propagated to the estimated quantitative maps. We propose using a distance metric learning method as a matching algorithm and a Singular Value Decomposition (SVD) to compress the dictionary, intending to promote the accuracy of MRF and expedite the matching process.
Material and Methods: In this investigation, a distance metric learning method, called the Relevant Component Analysis (RCA) was used to match the fingerprints from the undersampled data with a compressed dictionary to create quantitative maps accurately and rapidly. An Inversion Recovery Fast Imaging with Steady-State (IR-FISP) MRF sequence was simulated based on an Extended Phase Graph (EPG) on a digital brain phantom. The performance of our work was compared with the original MRF paper.
Results: Effectiveness of our method was evaluated with statistical analysis. Compared with the correlation algorithm and full-sized dictionary, this method acquires tissue parameter maps with more accuracy and better computational speed.
Conclusion: Our numerical results show that learning a distance metric of the undersampled training data accompanied by a compressed dictionary improves the accuracy of the MRF matching and overcomes the computation complexity.</abstract>
    <web_url>https://fbt.tums.ac.ir/index.php/fbt/article/view/234</web_url>
    <pdf_url>https://fbt.tums.ac.ir/index.php/fbt/article/download/234/149</pdf_url>
  </Article>
</Articles>
