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A review of 3D first-pass, whole-heart, myocardial perfusion cardiovascular magnetic resonance.

Fair MJ, Gatehouse PD, DiBella EV, Firmin DN - J Cardiovasc Magn Reson (2015)

Bottom Line: The mechanisms include rapid sequences, non-Cartesian k-space trajectories, reduced k-space acquisitions, parallel imaging reconstructions and compressed sensing.An attempt is made to explain, rather than simply state, the varying methods with the hope that it will give an appreciation of the different components making up a 3D FPP protocol.Basic estimates demonstrating the required total acceleration factors in typical 3D FPP cases are included, providing context for the extent that each acceleration method can contribute to the required imaging speed, as well as potential limitations in present 3D FPP literature.

View Article: PubMed Central - PubMed

Affiliation: National Heart & Lung Institute, Imperial College London, London, UK. M.Fair@rbht.nhs.uk.

ABSTRACT
A comprehensive review is undertaken of the methods available for 3D whole-heart first-pass perfusion (FPP) and their application to date, with particular focus on possible acceleration techniques. Following a summary of the parameters typically desired of 3D FPP methods, the review explains the mechanisms of key acceleration techniques and their potential use in FPP for attaining 3D acquisitions. The mechanisms include rapid sequences, non-Cartesian k-space trajectories, reduced k-space acquisitions, parallel imaging reconstructions and compressed sensing. An attempt is made to explain, rather than simply state, the varying methods with the hope that it will give an appreciation of the different components making up a 3D FPP protocol. Basic estimates demonstrating the required total acceleration factors in typical 3D FPP cases are included, providing context for the extent that each acceleration method can contribute to the required imaging speed, as well as potential limitations in present 3D FPP literature. Although many 3D FPP methods are too early in development for the type of clinical trials required to show any clear benefit over current 2D FPP methods, the review includes the small but growing quantity of clinical research work already using 3D FPP, alongside the more technical work. Broader challenges concerning FPP such as quantitative analysis are not covered, but challenges with particular impact on 3D FPP methods, particularly with regards to motion effects, are discussed along with anticipated future work in the field.

No MeSH data available.


K-space efficiencies. Three k-space acquisition modifications demonstrated for a 3D Cartesian sequence. Representations of partial Fourier in the phase-encoding (a) and readout (partial-echo) (b) directions are shown, with dashed lines denoting data points that are not acquired but later calculated (see text). Zero padding (c) has lines of ‘data’ filled with zeros added either side of the acquired data before reconstruction, artificially increasing resolution. An elliptical shutter (d) does not acquire the corner regions of k-space, as they are deemed less critical. Each of these methods can be applied in any encoding direction and those chosen here are simply illustrative
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Fig3: K-space efficiencies. Three k-space acquisition modifications demonstrated for a 3D Cartesian sequence. Representations of partial Fourier in the phase-encoding (a) and readout (partial-echo) (b) directions are shown, with dashed lines denoting data points that are not acquired but later calculated (see text). Zero padding (c) has lines of ‘data’ filled with zeros added either side of the acquired data before reconstruction, artificially increasing resolution. An elliptical shutter (d) does not acquire the corner regions of k-space, as they are deemed less critical. Each of these methods can be applied in any encoding direction and those chosen here are simply illustrative

Mentions: To achieve the acceleration required for 3D FPP, further reductions in raw data coverage are often applied in conjunction with the other methods discussed, although they are compatible with only some non-Cartesian methods (see Section Alternative k-space coverage). These k-space “efficiencies” or ‘tricks’ include methods such as partial Fourier, elliptical shutters, zero padding and zonal-imaging (see Fig. 3) and are described in this section. Many of the details of these techniques can be found in textbooks, such as [51] or [52].Fig. 3


A review of 3D first-pass, whole-heart, myocardial perfusion cardiovascular magnetic resonance.

Fair MJ, Gatehouse PD, DiBella EV, Firmin DN - J Cardiovasc Magn Reson (2015)

K-space efficiencies. Three k-space acquisition modifications demonstrated for a 3D Cartesian sequence. Representations of partial Fourier in the phase-encoding (a) and readout (partial-echo) (b) directions are shown, with dashed lines denoting data points that are not acquired but later calculated (see text). Zero padding (c) has lines of ‘data’ filled with zeros added either side of the acquired data before reconstruction, artificially increasing resolution. An elliptical shutter (d) does not acquire the corner regions of k-space, as they are deemed less critical. Each of these methods can be applied in any encoding direction and those chosen here are simply illustrative
© Copyright Policy - open-access
Related In: Results  -  Collection

License 1 - License 2
Show All Figures
getmorefigures.php?uid=PMC4522116&req=5

Fig3: K-space efficiencies. Three k-space acquisition modifications demonstrated for a 3D Cartesian sequence. Representations of partial Fourier in the phase-encoding (a) and readout (partial-echo) (b) directions are shown, with dashed lines denoting data points that are not acquired but later calculated (see text). Zero padding (c) has lines of ‘data’ filled with zeros added either side of the acquired data before reconstruction, artificially increasing resolution. An elliptical shutter (d) does not acquire the corner regions of k-space, as they are deemed less critical. Each of these methods can be applied in any encoding direction and those chosen here are simply illustrative
Mentions: To achieve the acceleration required for 3D FPP, further reductions in raw data coverage are often applied in conjunction with the other methods discussed, although they are compatible with only some non-Cartesian methods (see Section Alternative k-space coverage). These k-space “efficiencies” or ‘tricks’ include methods such as partial Fourier, elliptical shutters, zero padding and zonal-imaging (see Fig. 3) and are described in this section. Many of the details of these techniques can be found in textbooks, such as [51] or [52].Fig. 3

Bottom Line: The mechanisms include rapid sequences, non-Cartesian k-space trajectories, reduced k-space acquisitions, parallel imaging reconstructions and compressed sensing.An attempt is made to explain, rather than simply state, the varying methods with the hope that it will give an appreciation of the different components making up a 3D FPP protocol.Basic estimates demonstrating the required total acceleration factors in typical 3D FPP cases are included, providing context for the extent that each acceleration method can contribute to the required imaging speed, as well as potential limitations in present 3D FPP literature.

View Article: PubMed Central - PubMed

Affiliation: National Heart & Lung Institute, Imperial College London, London, UK. M.Fair@rbht.nhs.uk.

ABSTRACT
A comprehensive review is undertaken of the methods available for 3D whole-heart first-pass perfusion (FPP) and their application to date, with particular focus on possible acceleration techniques. Following a summary of the parameters typically desired of 3D FPP methods, the review explains the mechanisms of key acceleration techniques and their potential use in FPP for attaining 3D acquisitions. The mechanisms include rapid sequences, non-Cartesian k-space trajectories, reduced k-space acquisitions, parallel imaging reconstructions and compressed sensing. An attempt is made to explain, rather than simply state, the varying methods with the hope that it will give an appreciation of the different components making up a 3D FPP protocol. Basic estimates demonstrating the required total acceleration factors in typical 3D FPP cases are included, providing context for the extent that each acceleration method can contribute to the required imaging speed, as well as potential limitations in present 3D FPP literature. Although many 3D FPP methods are too early in development for the type of clinical trials required to show any clear benefit over current 2D FPP methods, the review includes the small but growing quantity of clinical research work already using 3D FPP, alongside the more technical work. Broader challenges concerning FPP such as quantitative analysis are not covered, but challenges with particular impact on 3D FPP methods, particularly with regards to motion effects, are discussed along with anticipated future work in the field.

No MeSH data available.