TY - GEN
T1 - Exact and stable interior ROI reconstruction for radial MRI
AU - Zhang, Jie
AU - Yu, Hengyong
AU - Corum, Curt
AU - Garwood, Michael
AU - Wang, Ge
PY - 2009
Y1 - 2009
N2 - MRI applications often require high spatial and/or temporal resolution within a region of interest (ROI) such as for perfusion studies. In theory, both spatial resolution and temporal resolution can be significantly improved using a ROI-focused MRI data acquisition scheme. However, in radial MRI, there is no such acquisition-based solution available. Traditional reconstruction methods to image the ROI by reducing the field of view produce aliasing artifacts when the dataset becomes truncated. Here we propose an interior MRI methodology to perform ROI reconstruction without artifacts. Methods: In contrast to the conventional wisdom that the interior problem does not have a unique solution, interior tomography has been recently proposed as an exact and stable solution to this longstanding problem. In this project, a ROI-focused radial MRI data acquisition scheme was developed, aided by a dedicated digital filter. We implemented this method in a 4T 90 cm bore Oxford magnet with a GE phantom and a transceiver TEM head coil. The parameters were 4 gauss/cm sonata gradients, 5 mm slice thickness, TE=30 ms, TR=200 ms, FOVs of 40 cm and 12 cm respectively. Results: Both numerical simulation and phantom experiments have demonstrated that the proposed interior MRI method can exactly reconstruct a ROI with increased spatial resolution (∼4 fold) while keeping the same temporal resolution. The image artifacts from truncated projections are effectively eliminated. No crosstalk with the outside ROI region is involved using the proposed method. Conclusions: Our interior radial MRI method can be used for zoomed-in and fast views of a particular ROI, which can be translated into significant advantages in clinical and pre-clinical applications of many types.
AB - MRI applications often require high spatial and/or temporal resolution within a region of interest (ROI) such as for perfusion studies. In theory, both spatial resolution and temporal resolution can be significantly improved using a ROI-focused MRI data acquisition scheme. However, in radial MRI, there is no such acquisition-based solution available. Traditional reconstruction methods to image the ROI by reducing the field of view produce aliasing artifacts when the dataset becomes truncated. Here we propose an interior MRI methodology to perform ROI reconstruction without artifacts. Methods: In contrast to the conventional wisdom that the interior problem does not have a unique solution, interior tomography has been recently proposed as an exact and stable solution to this longstanding problem. In this project, a ROI-focused radial MRI data acquisition scheme was developed, aided by a dedicated digital filter. We implemented this method in a 4T 90 cm bore Oxford magnet with a GE phantom and a transceiver TEM head coil. The parameters were 4 gauss/cm sonata gradients, 5 mm slice thickness, TE=30 ms, TR=200 ms, FOVs of 40 cm and 12 cm respectively. Results: Both numerical simulation and phantom experiments have demonstrated that the proposed interior MRI method can exactly reconstruct a ROI with increased spatial resolution (∼4 fold) while keeping the same temporal resolution. The image artifacts from truncated projections are effectively eliminated. No crosstalk with the outside ROI region is involved using the proposed method. Conclusions: Our interior radial MRI method can be used for zoomed-in and fast views of a particular ROI, which can be translated into significant advantages in clinical and pre-clinical applications of many types.
KW - Interior region of interest
KW - ROI
KW - ROI reconstruction
KW - Radial MRI
KW - Reduced FOV
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U2 - 10.1117/12.812035
DO - 10.1117/12.812035
M3 - Conference contribution
AN - SCOPUS:66749160993
SN - 9780819475091
T3 - Progress in Biomedical Optics and Imaging - Proceedings of SPIE
BT - Medical Imaging 2009
T2 - Medical Imaging 2009: Physics of Medical Imaging
Y2 - 9 February 2009 through 12 February 2009
ER -