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Quantification of myocardial perfusion with self-gated cardiovascular magnetic resonance.

Likhite D, Adluru G, Hu N, McGann C, DiBella E - J Cardiovasc Magn Reson (2015)

Bottom Line: The gated and the self-gated datasets were then quantified with standard methods.Regional myocardial blood flow estimates (MBFs) obtained using self-gated systole (0.64 ± 0.26 ml/min/g), self-gated diastole (0.64 ± 0.26 ml/min/g), and ECG-gated scans (0.65 ± 0.28 ml/min/g) were similar.Based on the criteria for interchangeable methods listed in the statistical analysis section, the MBF values estimated from self-gated and gated methods were not significantly different.

View Article: PubMed Central - PubMed

ABSTRACT

Background: Current myocardial perfusion measurements make use of an ECG-gated pulse sequence to track the uptake and washout of a gadolinium-based contrast agent. The use of a gated acquisition is a problem in situations with a poor ECG signal. Recently, an ungated perfusion acquisition was proposed but it is not known how accurately quantitative perfusion estimates can be made from such datasets that are acquired without any triggering signal.

Methods: An undersampled saturation recovery radial turboFLASH pulse sequence was used in 7 subjects to acquire dynamic contrast-enhanced images during free-breathing. A single saturation pulse was followed by acquisition of 4-5 slices after a delay of ~40 msec. This was repeated without pause and without any type of gating. The same pulse sequence, with ECG-gating, was used to acquire gated data as a ground truth. An iterative spatio-temporal constrained reconstruction was used to reconstruct the undersampled images. After reconstruction, the ungated images were retrospectively binned ("self-gated") into two cardiac phases using a region of interest based technique and deformably registered into near-systole and near-diastole. The gated and the self-gated datasets were then quantified with standard methods.

Results: Regional myocardial blood flow estimates (MBFs) obtained using self-gated systole (0.64 ± 0.26 ml/min/g), self-gated diastole (0.64 ± 0.26 ml/min/g), and ECG-gated scans (0.65 ± 0.28 ml/min/g) were similar. Based on the criteria for interchangeable methods listed in the statistical analysis section, the MBF values estimated from self-gated and gated methods were not significantly different.

Conclusion: The self-gated technique for quantification of regional myocardial perfusion matched ECG-gated perfusion measurements well in normal subjects at rest. Self-gated systolic perfusion values matched ECG-gated perfusion values better than did diastolic values.

No MeSH data available.


Histogram plot showing the distribution of the MBF parameter using a) self-gated systole and b) self-gated diastole, along with the gated acquisition MBFs. The histograms were created from the seven datasets, three slices each with six regions in each slice.
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Fig9: Histogram plot showing the distribution of the MBF parameter using a) self-gated systole and b) self-gated diastole, along with the gated acquisition MBFs. The histograms were created from the seven datasets, three slices each with six regions in each slice.

Mentions: Figure 6 shows the Bland-Altman plot for the systolic and diastolic self-gated techniques. The diastolic self-gated result shows a wider spread, likely due to more challenging segmentation. Another way to look at the data is in Figure 7, which shows a paired MBF plot between the 18 MBF values (3 slices × 6 regions per slice) estimated using gated and the 18 MBF values estimated using self-gated systole for each of the seven subjects. Three different colors represent the three different slices being compared. Figure 8 shows the same type of plot for self-gated diastole. It can be seen that for each dataset the gated as well as the self-gated acquisitions give a similar mean. Figure 9 shows a distribution of the MBF from the gated acquisition and the proposed ungated acquisition for all datasets, all slices and all regions. One can see a similar distribution for both gated and the self-gated acquisition.Figure 6


Quantification of myocardial perfusion with self-gated cardiovascular magnetic resonance.

Likhite D, Adluru G, Hu N, McGann C, DiBella E - J Cardiovasc Magn Reson (2015)

Histogram plot showing the distribution of the MBF parameter using a) self-gated systole and b) self-gated diastole, along with the gated acquisition MBFs. The histograms were created from the seven datasets, three slices each with six regions in each slice.
© Copyright Policy - open-access
Related In: Results  -  Collection

License 1 - License 2
Show All Figures
getmorefigures.php?uid=PMC4325943&req=5

Fig9: Histogram plot showing the distribution of the MBF parameter using a) self-gated systole and b) self-gated diastole, along with the gated acquisition MBFs. The histograms were created from the seven datasets, three slices each with six regions in each slice.
Mentions: Figure 6 shows the Bland-Altman plot for the systolic and diastolic self-gated techniques. The diastolic self-gated result shows a wider spread, likely due to more challenging segmentation. Another way to look at the data is in Figure 7, which shows a paired MBF plot between the 18 MBF values (3 slices × 6 regions per slice) estimated using gated and the 18 MBF values estimated using self-gated systole for each of the seven subjects. Three different colors represent the three different slices being compared. Figure 8 shows the same type of plot for self-gated diastole. It can be seen that for each dataset the gated as well as the self-gated acquisitions give a similar mean. Figure 9 shows a distribution of the MBF from the gated acquisition and the proposed ungated acquisition for all datasets, all slices and all regions. One can see a similar distribution for both gated and the self-gated acquisition.Figure 6

Bottom Line: The gated and the self-gated datasets were then quantified with standard methods.Regional myocardial blood flow estimates (MBFs) obtained using self-gated systole (0.64 ± 0.26 ml/min/g), self-gated diastole (0.64 ± 0.26 ml/min/g), and ECG-gated scans (0.65 ± 0.28 ml/min/g) were similar.Based on the criteria for interchangeable methods listed in the statistical analysis section, the MBF values estimated from self-gated and gated methods were not significantly different.

View Article: PubMed Central - PubMed

ABSTRACT

Background: Current myocardial perfusion measurements make use of an ECG-gated pulse sequence to track the uptake and washout of a gadolinium-based contrast agent. The use of a gated acquisition is a problem in situations with a poor ECG signal. Recently, an ungated perfusion acquisition was proposed but it is not known how accurately quantitative perfusion estimates can be made from such datasets that are acquired without any triggering signal.

Methods: An undersampled saturation recovery radial turboFLASH pulse sequence was used in 7 subjects to acquire dynamic contrast-enhanced images during free-breathing. A single saturation pulse was followed by acquisition of 4-5 slices after a delay of ~40 msec. This was repeated without pause and without any type of gating. The same pulse sequence, with ECG-gating, was used to acquire gated data as a ground truth. An iterative spatio-temporal constrained reconstruction was used to reconstruct the undersampled images. After reconstruction, the ungated images were retrospectively binned ("self-gated") into two cardiac phases using a region of interest based technique and deformably registered into near-systole and near-diastole. The gated and the self-gated datasets were then quantified with standard methods.

Results: Regional myocardial blood flow estimates (MBFs) obtained using self-gated systole (0.64 ± 0.26 ml/min/g), self-gated diastole (0.64 ± 0.26 ml/min/g), and ECG-gated scans (0.65 ± 0.28 ml/min/g) were similar. Based on the criteria for interchangeable methods listed in the statistical analysis section, the MBF values estimated from self-gated and gated methods were not significantly different.

Conclusion: The self-gated technique for quantification of regional myocardial perfusion matched ECG-gated perfusion measurements well in normal subjects at rest. Self-gated systolic perfusion values matched ECG-gated perfusion values better than did diastolic values.

No MeSH data available.