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Dynamic susceptibility contrast parametric imaging using accelerated dual-contrast echo planar imaging with keyhole
Liliana L Caldeira1, Seong Dae Yun1, Nuno A da Silva1
1Institute of Neuroscience and Medicine 4, Medical Imaging Physics, Forschungszentrum Jülich GmbH, Jülich, Germany.
Journal of Magnetic Resonance Imaging : JMRI
|January 9, 2019
Summary
Echo planar imaging with keyhole (EPIK) enhances dynamic susceptibility contrast MRI by providing dual-contrast imaging with greater spatial coverage and reduced distortion compared to standard EPI. This method improves arterial input function estimation for brain tumor analysis.
Area of Science:
- Magnetic Resonance Imaging
- Medical Imaging Physics
Background:
- Echo planar imaging (EPI) offers high temporal resolution for dynamic susceptibility contrast MRI (DSC-MRI).
- EPI's long readout duration limits spatial coverage and multi-contrast capabilities in DSC-MRI.
Purpose of the Study:
- To develop and evaluate EPI with keyhole (EPIK) for DSC-MRI, enabling dual-contrast imaging with expanded spatial coverage.
- To compare the performance of EPIK against conventional EPI in brain tumor patients.
Main Methods:
- Prospective study involving one healthy subject and 17 brain tumor patients.
- Utilized 3T accelerated EPI and dual-contrast EPIK sequences.
- Compared parametric images (CBF, CBV) and arterial input function (AIF) derived from both EPI and EPIK.
Main Results:
- EPIK achieved dual-contrast imaging (TEs 13/33 msec) with 24 slices and reduced distortion, surpassing EPI's single contrast (TE 32 msec) with 20 slices, at the same temporal resolution (1.5 sec).
- Parametric values like AIF peak, time-to-peak (TTP), and tumor-to-brain ratio (TBR) showed comparable characteristics between EPIK and EPI.
- EPIK provided T1-corrected parametric images without a second contrast injection, enhancing AIF estimation.
Conclusions:
- EPIK is a viable DSC-MRI technique offering improved spatial coverage and dual-contrast capabilities over standard EPI.
- The dual-contrast data from EPIK facilitates enhanced AIF estimation and T1-corrected parametric imaging.
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