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Undersampled cine 3D tagging for rapid assessment of cardiac motion.

Stoeck CT, Manka R, Boesiger P, Kozerke S - J Cardiovasc Magn Reson (2012)

Bottom Line: Comparison of results from fully sampled in-vivo data acquired with prospectively undersampled acquisitions showed a mean difference in circumferential shortening of -0.14 ± 5.18% and 0.71 ± 6.16% for R = 3 and 4.In patients peak, circumferential shortening was significantly reduced (p < 0.002 for all patients) in regions with late gadolinium enhancement.Undersampled cine 3D tagging enables significant reduction in scan time of whole-heart tagging and facilitates quantification of shortening, rotation and torsion of the left ventricle without adding significant errors compared to previous 3D tagging approaches.

View Article: PubMed Central - PubMed

Affiliation: Institute for Biomedical Engineering, University and ETH Zurich, Gloriastrasse 35, 8092, Zurich, Switzerland.

ABSTRACT

Background: CMR allows investigating cardiac contraction, rotation and torsion non-invasively by the use of tagging sequences. Three-dimensional tagging has been proposed to cover the whole-heart but data acquisition requires three consecutive breath holds and hence demands considerable patient cooperation. In this study we have implemented and studied k-t undersampled cine 3D tagging in conjunction with k-t PCA reconstruction to potentially permit for single breath-hold acquisitions.

Methods: The performance of undersampled cine 3D tagging was investigated using computer simulations and in-vivo measurements in 8 healthy subjects and 5 patients with myocardial infarction. Fully sampled data was obtained and compared to retrospectively and prospectively undersampled acquisitions. Fully sampled data was acquired in three consecutive breath holds. Prospectively undersampled data was obtained within a single breath hold. Based on harmonic phase (HARP) analysis, circumferential shortening, rotation and torsion were compared between fully sampled and undersampled data using Bland-Altman and linear regression analysis.

Results: In computer simulations, the error for circumferential shortening was 2.8 ± 2.3% and 2.7 ± 2.1% for undersampling rates of R = 3 and 4 respectively. Errors in ventricular rotation were 2.5 ± 1.9% and 3.0 ± 2.2% for R = 3 and 4. Comparison of results from fully sampled in-vivo data acquired with prospectively undersampled acquisitions showed a mean difference in circumferential shortening of -0.14 ± 5.18% and 0.71 ± 6.16% for R = 3 and 4. The mean differences in rotation were 0.44 ± 1.8° and 0.73 ± 1.67° for R = 3 and 4, respectively. In patients peak, circumferential shortening was significantly reduced (p < 0.002 for all patients) in regions with late gadolinium enhancement.

Conclusion: Undersampled cine 3D tagging enables significant reduction in scan time of whole-heart tagging and facilitates quantification of shortening, rotation and torsion of the left ventricle without adding significant errors compared to previous 3D tagging approaches.

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Related in: MedlinePlus

Bland Altman plots of point-wise and sector-wise comparison of fully sampled and retrospectively undersampled in-vivo data (R = 3 and 4) in healthy volunteers. Mean differences (grey) and 95% levels of agreement (2SD) (black) are indicated by the dashed lines. Analysis was performed on the entire LV. Point-wise comparison was performed for the polar coordinates r (a, c) and ϕ (b, d) for each tracked point. Circumferential shortening (e, g) and rotation (f, h) were compared per sector.
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Figure 7: Bland Altman plots of point-wise and sector-wise comparison of fully sampled and retrospectively undersampled in-vivo data (R = 3 and 4) in healthy volunteers. Mean differences (grey) and 95% levels of agreement (2SD) (black) are indicated by the dashed lines. Analysis was performed on the entire LV. Point-wise comparison was performed for the polar coordinates r (a, c) and ϕ (b, d) for each tracked point. Circumferential shortening (e, g) and rotation (f, h) were compared per sector.

Mentions: In Figure 7 shows the Bland-Altman comparison of fully sampled and retrospectively undersampled in-vivo data for R = 3 and 4. Dashed lines represent the mean difference (light grey) and the 95% limit of agreement (2SD) (black). In Figure 7a-d provides the comparison of radial coordinates (r = radius and ϕ = angle) of tracked contour points. Mean differences ± 2SD of r were 0.0 ± 3.3% and −0.2 ± 4.1% for R = 3 and 4 and −0.2 ± 1.9° and −0.3 ± 2.2° for ϕ. In Figure 7e-h Bland-Altman plots for peak circumferential shortening and peak rotation are given. The mean differences ± 2SD for circumferential shortening were −0.2 ± 4.1% and −0.1 ± 4.2% for R = 3 and 4. For rotation, mean differences ± 2SD were 0.5 ± 1.8° and 0.7 ± 1.7° for R = 3 and 4. The mean differences of torsion were 0.45 ± 2.22° (p = N.S.) and 0.05 ± 2.24° (p = N.S.) for R = 3 and 4, respectively.


Undersampled cine 3D tagging for rapid assessment of cardiac motion.

Stoeck CT, Manka R, Boesiger P, Kozerke S - J Cardiovasc Magn Reson (2012)

Bland Altman plots of point-wise and sector-wise comparison of fully sampled and retrospectively undersampled in-vivo data (R = 3 and 4) in healthy volunteers. Mean differences (grey) and 95% levels of agreement (2SD) (black) are indicated by the dashed lines. Analysis was performed on the entire LV. Point-wise comparison was performed for the polar coordinates r (a, c) and ϕ (b, d) for each tracked point. Circumferential shortening (e, g) and rotation (f, h) were compared per sector.
© Copyright Policy - open-access
Related In: Results  -  Collection

License
Show All Figures
getmorefigures.php?uid=PMC3472184&req=5

Figure 7: Bland Altman plots of point-wise and sector-wise comparison of fully sampled and retrospectively undersampled in-vivo data (R = 3 and 4) in healthy volunteers. Mean differences (grey) and 95% levels of agreement (2SD) (black) are indicated by the dashed lines. Analysis was performed on the entire LV. Point-wise comparison was performed for the polar coordinates r (a, c) and ϕ (b, d) for each tracked point. Circumferential shortening (e, g) and rotation (f, h) were compared per sector.
Mentions: In Figure 7 shows the Bland-Altman comparison of fully sampled and retrospectively undersampled in-vivo data for R = 3 and 4. Dashed lines represent the mean difference (light grey) and the 95% limit of agreement (2SD) (black). In Figure 7a-d provides the comparison of radial coordinates (r = radius and ϕ = angle) of tracked contour points. Mean differences ± 2SD of r were 0.0 ± 3.3% and −0.2 ± 4.1% for R = 3 and 4 and −0.2 ± 1.9° and −0.3 ± 2.2° for ϕ. In Figure 7e-h Bland-Altman plots for peak circumferential shortening and peak rotation are given. The mean differences ± 2SD for circumferential shortening were −0.2 ± 4.1% and −0.1 ± 4.2% for R = 3 and 4. For rotation, mean differences ± 2SD were 0.5 ± 1.8° and 0.7 ± 1.7° for R = 3 and 4. The mean differences of torsion were 0.45 ± 2.22° (p = N.S.) and 0.05 ± 2.24° (p = N.S.) for R = 3 and 4, respectively.

Bottom Line: Comparison of results from fully sampled in-vivo data acquired with prospectively undersampled acquisitions showed a mean difference in circumferential shortening of -0.14 ± 5.18% and 0.71 ± 6.16% for R = 3 and 4.In patients peak, circumferential shortening was significantly reduced (p < 0.002 for all patients) in regions with late gadolinium enhancement.Undersampled cine 3D tagging enables significant reduction in scan time of whole-heart tagging and facilitates quantification of shortening, rotation and torsion of the left ventricle without adding significant errors compared to previous 3D tagging approaches.

View Article: PubMed Central - PubMed

Affiliation: Institute for Biomedical Engineering, University and ETH Zurich, Gloriastrasse 35, 8092, Zurich, Switzerland.

ABSTRACT

Background: CMR allows investigating cardiac contraction, rotation and torsion non-invasively by the use of tagging sequences. Three-dimensional tagging has been proposed to cover the whole-heart but data acquisition requires three consecutive breath holds and hence demands considerable patient cooperation. In this study we have implemented and studied k-t undersampled cine 3D tagging in conjunction with k-t PCA reconstruction to potentially permit for single breath-hold acquisitions.

Methods: The performance of undersampled cine 3D tagging was investigated using computer simulations and in-vivo measurements in 8 healthy subjects and 5 patients with myocardial infarction. Fully sampled data was obtained and compared to retrospectively and prospectively undersampled acquisitions. Fully sampled data was acquired in three consecutive breath holds. Prospectively undersampled data was obtained within a single breath hold. Based on harmonic phase (HARP) analysis, circumferential shortening, rotation and torsion were compared between fully sampled and undersampled data using Bland-Altman and linear regression analysis.

Results: In computer simulations, the error for circumferential shortening was 2.8 ± 2.3% and 2.7 ± 2.1% for undersampling rates of R = 3 and 4 respectively. Errors in ventricular rotation were 2.5 ± 1.9% and 3.0 ± 2.2% for R = 3 and 4. Comparison of results from fully sampled in-vivo data acquired with prospectively undersampled acquisitions showed a mean difference in circumferential shortening of -0.14 ± 5.18% and 0.71 ± 6.16% for R = 3 and 4. The mean differences in rotation were 0.44 ± 1.8° and 0.73 ± 1.67° for R = 3 and 4, respectively. In patients peak, circumferential shortening was significantly reduced (p < 0.002 for all patients) in regions with late gadolinium enhancement.

Conclusion: Undersampled cine 3D tagging enables significant reduction in scan time of whole-heart tagging and facilitates quantification of shortening, rotation and torsion of the left ventricle without adding significant errors compared to previous 3D tagging approaches.

Show MeSH
Related in: MedlinePlus