Limits...
Pulmonary artery stiffness assessed by velocity-encoding MRI: comparison of techniques

View Article: PubMed Central - HTML

AUTOMATICALLY GENERATED EXCERPT
Please rate it.

The loss of PA compliance has considerable influence on elevated right-ventricle workload... MRI velocity-encoding is an effective technique for assessing pulse-wave-velocity (PWV) by measuring the disturbances in flow or vessel diameter the pressure wave causes... Nevertheless, no data is available that compares the two methods, especially over wide range of PWV values, or at 3.0-Tesla, which is the purpose of this study... The first sequence was optimized for high temporal-resolution (heart-phases=128, pixel-size =1.25mm, venc=150cm/s), and implemented twice: at main PA and either right or left PA locations (Figure 1)... The second sequence was optimized for high spatial-resolution (heart-phases=80, pixel-size=0.6mm, venc=150cm/s), and implemented once at the main PA location (Figure 1)... The TT and QA methods showed good agreement (P>0.1)... The Bland-Altman analysis resulted in mean±SD of 0.13±0.35m/s for the measurement differences... The corresponding correlation coefficients were r=0.96/0.92 and r=0.94/0.90... The TT and QA techniques showed good agreement in estimating PWV, although the QA method resulted in larger variabilities than in TT... The use of 3.0-Tesla allowed for improving the temporal and spatial resolutions in the TT and QA sequences, respectively... In conclusion, each technique has its own advantages and disadvantages... The choice depends on patient condition, heart rate, and required image quality.

No MeSH data available.


Planning of the pulmonary flow imaging planes. An axial slice showing the main, right, and left pulmonary arteries (MPA, RPA and LPA, respectively). Two planes are prescribed perpendicular to the flow direction in the pulmonary artery. Plane 1 is perpendicular to MPA, while plane 2 is perpendicular to LPA or RPA. The distance along the pulmonary artery between the two measuring sites (Δx) is used in calculating PWV.
© Copyright Policy - open-access
Related In: Results  -  Collection


getmorefigures.php?uid=PMC3106526&req=5

Figure 1: Planning of the pulmonary flow imaging planes. An axial slice showing the main, right, and left pulmonary arteries (MPA, RPA and LPA, respectively). Two planes are prescribed perpendicular to the flow direction in the pulmonary artery. Plane 1 is perpendicular to MPA, while plane 2 is perpendicular to LPA or RPA. The distance along the pulmonary artery between the two measuring sites (Δx) is used in calculating PWV.

Mentions: Twenty-five volunteers(Table 1) were scanned on 3.0-Tesla Siemens scanner. Two velocity-encoding sequences were applied to each subject. The first sequence was optimized for high temporal-resolution (heart-phases=128, pixel-size =1.25mm, venc=150cm/s), and implemented twice: at main PA and either right or left PA locations (Figure 1). The second sequence was optimized for high spatial-resolution (heart-phases=80, pixel-size=0.6mm, venc=150cm/s), and implemented once at the main PA location (Figure 1). The images were analyzed with MATLAB, as previously described for TT and QA methods( Figures 2 and 3) [2,3]. Inter-method, inter-observer and intra-observer variabilities were calculated using Bland-Altman analysis.


Pulmonary artery stiffness assessed by velocity-encoding MRI: comparison of techniques
Planning of the pulmonary flow imaging planes. An axial slice showing the main, right, and left pulmonary arteries (MPA, RPA and LPA, respectively). Two planes are prescribed perpendicular to the flow direction in the pulmonary artery. Plane 1 is perpendicular to MPA, while plane 2 is perpendicular to LPA or RPA. The distance along the pulmonary artery between the two measuring sites (Δx) is used in calculating PWV.
© Copyright Policy - open-access
Related In: Results  -  Collection

Show All Figures
getmorefigures.php?uid=PMC3106526&req=5

Figure 1: Planning of the pulmonary flow imaging planes. An axial slice showing the main, right, and left pulmonary arteries (MPA, RPA and LPA, respectively). Two planes are prescribed perpendicular to the flow direction in the pulmonary artery. Plane 1 is perpendicular to MPA, while plane 2 is perpendicular to LPA or RPA. The distance along the pulmonary artery between the two measuring sites (Δx) is used in calculating PWV.
Mentions: Twenty-five volunteers(Table 1) were scanned on 3.0-Tesla Siemens scanner. Two velocity-encoding sequences were applied to each subject. The first sequence was optimized for high temporal-resolution (heart-phases=128, pixel-size =1.25mm, venc=150cm/s), and implemented twice: at main PA and either right or left PA locations (Figure 1). The second sequence was optimized for high spatial-resolution (heart-phases=80, pixel-size=0.6mm, venc=150cm/s), and implemented once at the main PA location (Figure 1). The images were analyzed with MATLAB, as previously described for TT and QA methods( Figures 2 and 3) [2,3]. Inter-method, inter-observer and intra-observer variabilities were calculated using Bland-Altman analysis.

View Article: PubMed Central - HTML

AUTOMATICALLY GENERATED EXCERPT
Please rate it.

The loss of PA compliance has considerable influence on elevated right-ventricle workload... MRI velocity-encoding is an effective technique for assessing pulse-wave-velocity (PWV) by measuring the disturbances in flow or vessel diameter the pressure wave causes... Nevertheless, no data is available that compares the two methods, especially over wide range of PWV values, or at 3.0-Tesla, which is the purpose of this study... The first sequence was optimized for high temporal-resolution (heart-phases=128, pixel-size =1.25mm, venc=150cm/s), and implemented twice: at main PA and either right or left PA locations (Figure 1)... The second sequence was optimized for high spatial-resolution (heart-phases=80, pixel-size=0.6mm, venc=150cm/s), and implemented once at the main PA location (Figure 1)... The TT and QA methods showed good agreement (P>0.1)... The Bland-Altman analysis resulted in mean±SD of 0.13±0.35m/s for the measurement differences... The corresponding correlation coefficients were r=0.96/0.92 and r=0.94/0.90... The TT and QA techniques showed good agreement in estimating PWV, although the QA method resulted in larger variabilities than in TT... The use of 3.0-Tesla allowed for improving the temporal and spatial resolutions in the TT and QA sequences, respectively... In conclusion, each technique has its own advantages and disadvantages... The choice depends on patient condition, heart rate, and required image quality.

No MeSH data available.