Dataset Information

Three-dimensional heart locator and compressed sensing for whole-heart MR angiography.

ABSTRACT:

Purpose

We sought to develop a whole-heart magnetic resonance angiography technique with three-dimensional (3D) respiratory motion compensation and reduced scan time.

Methods

A novel respiratory motion compensation method was implemented that acquires a 1D navigator (NAV) and a low-resolution 3D-image of the heart (3D-LOC) just before the angiography data. The central 10% of SSFP k-space was fully acquired using NAV-gating, and then 10% of peripheral k-space was randomly undersampled to complete the scan. Spatial registration of the 3D-LOC information was used to correct the central and peripheral k-space lines for the bulk respiratory motion in three dimensions, and then the remaining k-space data was estimated using compressed sensing (CS). Ten volunteers each underwent two angiography acquisitions with 1 mm(3) resolution: (i) conventional NAV with CS, and (ii) the new 3D-LOC with CS.

Results

Compared with conventional NAV, the new 3D-LOC with CS technique had a shorter scan time (4.8 ± 1.1 versus 6.3 ± 1.7 min; P < 0.001), better objective vessel sharpness for all three coronary arteries (P < 0.05), and no difference in subjective vessel sharpness for all three coronary arteries.

Conclusion

Compared with conventional NAV with CS, acceleration and respiratory motion correction using 3D-LOC with CS reduces scan time and improves objective vessel sharpness.

SUBMITTER: Moghari MH

PROVIDER: S-EPMC5292940 | biostudies-literature | 2016 May

REPOSITORIES: biostudies-literature

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Publications

Three-dimensional heart locator and compressed sensing for whole-heart MR angiography.

Moghari Mehdi H MH Annese David D Geva Tal T Powell Andrew J AJ

Magnetic resonance in medicine 20150610 5

<h4>Purpose</h4>We sought to develop a whole-heart magnetic resonance angiography technique with three-dimensional (3D) respiratory motion compensation and reduced scan time.<h4>Methods</h4>A novel respiratory motion compensation method was implemented that acquires a 1D navigator (NAV) and a low-resolution 3D-image of the heart (3D-LOC) just before the angiography data. The central 10% of SSFP k-space was fully acquired using NAV-gating, and then 10% of peripheral k-space was randomly undersamp ...[more]

PMID: 26069182

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Dataset Information

Three-dimensional heart locator and compressed sensing for whole-heart MR angiography.

Purpose

Methods

Results

Conclusion

Publications

Three-dimensional heart locator and compressed sensing for whole-heart MR angiography.

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