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Impact of motion correction on reproducibility and spatial variability of quantitative myocardial T2 mapping.

Roujol S, Basha TA, Weingärtner S, Akçakaya M, Berg S, Manning WJ, Nezafat R - J Cardiovasc Magn Reson (2015)

Bottom Line: In-plane myocardial motion was corrected using an adaptive registration of varying contrast-weighted images for improved tissue characterization (ARCTIC).ARCTIC led to increased DSC in BH data (0.85 ± 0.08 vs. 0.90 ± 0.02, p = 0.007), FB data (0.78 ± 0.13 vs. 0.90 ± 0.21, p < 0.001), and FB + NAV data (0.86 ± 0.05 vs. 0.90 ± 0.02, p = 0.002), and reduced MBE in BH data (0.90 ± 0.40 vs. 0.64 ± 0.19 mm, p = 0.005), FB data (1.21 ± 0.65 vs. 0.63 ± 0.10 mm, p < 0.001), and FB + NAV data (0.81 ± 0.21 vs. 0.63 ± 0.08 mm, p < 0.001).The ARCTIC technique substantially reduces spatial mis-alignment among T2-weighted images and improves the reproducibility and spatial variability of in-vivo T2 mapping.

View Article: PubMed Central - PubMed

Affiliation: Department of Medicine (Cardiovascular Division), Beth Israel Deaconess Medical Center, 330 Brookline Ave, Boston, MA, 02215, USA. sroujol@bidmc.harvard.edu.

ABSTRACT

Background: To evaluate and quantify the impact of a novel image-based motion correction technique in myocardial T2 mapping in terms of measurement reproducibility and spatial variability.

Methods: Twelve healthy adult subjects were imaged using breath-hold (BH), free breathing (FB), and free breathing with respiratory navigator gating (FB + NAV) myocardial T2 mapping sequences. Fifty patients referred for clinical CMR were imaged using the FB + NAV sequence. All sequences used a T2 prepared (T2prep) steady-state free precession acquisition. In-plane myocardial motion was corrected using an adaptive registration of varying contrast-weighted images for improved tissue characterization (ARCTIC). DICE similarity coefficient (DSC) and myocardial boundary errors (MBE) were measured to quantify the motion estimation accuracy in healthy subjects. T2 mapping reproducibility and spatial variability were evaluated in healthy subjects using 5 repetitions of the FB + NAV sequence with either 4 or 20 T2prep echo times (TE). Subjective T2 map quality was assessed in patients by an experienced reader using a 4-point scale (1-non diagnostic, 4-excellent).

Results: ARCTIC led to increased DSC in BH data (0.85 ± 0.08 vs. 0.90 ± 0.02, p = 0.007), FB data (0.78 ± 0.13 vs. 0.90 ± 0.21, p < 0.001), and FB + NAV data (0.86 ± 0.05 vs. 0.90 ± 0.02, p = 0.002), and reduced MBE in BH data (0.90 ± 0.40 vs. 0.64 ± 0.19 mm, p = 0.005), FB data (1.21 ± 0.65 vs. 0.63 ± 0.10 mm, p < 0.001), and FB + NAV data (0.81 ± 0.21 vs. 0.63 ± 0.08 mm, p < 0.001). Improved reproducibility (4TE: 5.3 ± 2.5 ms vs. 4.0 ± 1.5 ms, p = 0.016; 20TE: 3.9 ± 2.3 ms vs. 2.2 ± 0.5 ms, p = 0.002), reduced spatial variability (4TE: 12.8 ± 3.5 ms vs. 10.3 ± 2.5 ms, p < 0.001; 20TE: 9.7 ± 3.5 ms vs. 7.5 ± 1.4 ms) and improved subjective score of T2 map quality (3.43 ± 0.79 vs. 3.69 ± 0.55, p < 0.001) were obtained using ARCTIC.

Conclusions: The ARCTIC technique substantially reduces spatial mis-alignment among T2-weighted images and improves the reproducibility and spatial variability of in-vivo T2 mapping.

No MeSH data available.


Related in: MedlinePlus

T2 scans from one subject acquired using the T2P4TE sequence under breath-hold (BH), free breathing (FB), and free breathing with respiratory navigator gating (FB + NAV). Data are shown without (uncorrected) and with (motion corrected) in-plane motion correction. The endocardial contour of the LV myocardium, drawn on the reference image (1st image) of each scan, is reported in all subsequent T2-weighted images to facilitate visual motion assessment. Misalignments observed among uncorrected images (red arrows) were substantially reduced after in-plane motion correction using ARCTIC. Furthermore, artifacts in uncorrected T2 maps (white arrows) were reduced in motion corrected T2 maps
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Fig1: T2 scans from one subject acquired using the T2P4TE sequence under breath-hold (BH), free breathing (FB), and free breathing with respiratory navigator gating (FB + NAV). Data are shown without (uncorrected) and with (motion corrected) in-plane motion correction. The endocardial contour of the LV myocardium, drawn on the reference image (1st image) of each scan, is reported in all subsequent T2-weighted images to facilitate visual motion assessment. Misalignments observed among uncorrected images (red arrows) were substantially reduced after in-plane motion correction using ARCTIC. Furthermore, artifacts in uncorrected T2 maps (white arrows) were reduced in motion corrected T2 maps

Mentions: Figure 1 shows an example of the remaining in-plane motion between T2-weighted images acquired in one healthy subject using the T2P4TE sequence under breath-hold, free breathing, and free breathing with respiratory navigator gating. Motion artifacts can be observed in the reconstructed T2 maps (see white arrows). In-plane motion correction improves the spatial alignment of T2-weighted images and results in visually improved T2 map quality (Figure 1).Fig. 1


Impact of motion correction on reproducibility and spatial variability of quantitative myocardial T2 mapping.

Roujol S, Basha TA, Weingärtner S, Akçakaya M, Berg S, Manning WJ, Nezafat R - J Cardiovasc Magn Reson (2015)

T2 scans from one subject acquired using the T2P4TE sequence under breath-hold (BH), free breathing (FB), and free breathing with respiratory navigator gating (FB + NAV). Data are shown without (uncorrected) and with (motion corrected) in-plane motion correction. The endocardial contour of the LV myocardium, drawn on the reference image (1st image) of each scan, is reported in all subsequent T2-weighted images to facilitate visual motion assessment. Misalignments observed among uncorrected images (red arrows) were substantially reduced after in-plane motion correction using ARCTIC. Furthermore, artifacts in uncorrected T2 maps (white arrows) were reduced in motion corrected T2 maps
© Copyright Policy - open-access
Related In: Results  -  Collection

License 1 - License 2
Show All Figures
getmorefigures.php?uid=PMC4465156&req=5

Fig1: T2 scans from one subject acquired using the T2P4TE sequence under breath-hold (BH), free breathing (FB), and free breathing with respiratory navigator gating (FB + NAV). Data are shown without (uncorrected) and with (motion corrected) in-plane motion correction. The endocardial contour of the LV myocardium, drawn on the reference image (1st image) of each scan, is reported in all subsequent T2-weighted images to facilitate visual motion assessment. Misalignments observed among uncorrected images (red arrows) were substantially reduced after in-plane motion correction using ARCTIC. Furthermore, artifacts in uncorrected T2 maps (white arrows) were reduced in motion corrected T2 maps
Mentions: Figure 1 shows an example of the remaining in-plane motion between T2-weighted images acquired in one healthy subject using the T2P4TE sequence under breath-hold, free breathing, and free breathing with respiratory navigator gating. Motion artifacts can be observed in the reconstructed T2 maps (see white arrows). In-plane motion correction improves the spatial alignment of T2-weighted images and results in visually improved T2 map quality (Figure 1).Fig. 1

Bottom Line: In-plane myocardial motion was corrected using an adaptive registration of varying contrast-weighted images for improved tissue characterization (ARCTIC).ARCTIC led to increased DSC in BH data (0.85 ± 0.08 vs. 0.90 ± 0.02, p = 0.007), FB data (0.78 ± 0.13 vs. 0.90 ± 0.21, p < 0.001), and FB + NAV data (0.86 ± 0.05 vs. 0.90 ± 0.02, p = 0.002), and reduced MBE in BH data (0.90 ± 0.40 vs. 0.64 ± 0.19 mm, p = 0.005), FB data (1.21 ± 0.65 vs. 0.63 ± 0.10 mm, p < 0.001), and FB + NAV data (0.81 ± 0.21 vs. 0.63 ± 0.08 mm, p < 0.001).The ARCTIC technique substantially reduces spatial mis-alignment among T2-weighted images and improves the reproducibility and spatial variability of in-vivo T2 mapping.

View Article: PubMed Central - PubMed

Affiliation: Department of Medicine (Cardiovascular Division), Beth Israel Deaconess Medical Center, 330 Brookline Ave, Boston, MA, 02215, USA. sroujol@bidmc.harvard.edu.

ABSTRACT

Background: To evaluate and quantify the impact of a novel image-based motion correction technique in myocardial T2 mapping in terms of measurement reproducibility and spatial variability.

Methods: Twelve healthy adult subjects were imaged using breath-hold (BH), free breathing (FB), and free breathing with respiratory navigator gating (FB + NAV) myocardial T2 mapping sequences. Fifty patients referred for clinical CMR were imaged using the FB + NAV sequence. All sequences used a T2 prepared (T2prep) steady-state free precession acquisition. In-plane myocardial motion was corrected using an adaptive registration of varying contrast-weighted images for improved tissue characterization (ARCTIC). DICE similarity coefficient (DSC) and myocardial boundary errors (MBE) were measured to quantify the motion estimation accuracy in healthy subjects. T2 mapping reproducibility and spatial variability were evaluated in healthy subjects using 5 repetitions of the FB + NAV sequence with either 4 or 20 T2prep echo times (TE). Subjective T2 map quality was assessed in patients by an experienced reader using a 4-point scale (1-non diagnostic, 4-excellent).

Results: ARCTIC led to increased DSC in BH data (0.85 ± 0.08 vs. 0.90 ± 0.02, p = 0.007), FB data (0.78 ± 0.13 vs. 0.90 ± 0.21, p < 0.001), and FB + NAV data (0.86 ± 0.05 vs. 0.90 ± 0.02, p = 0.002), and reduced MBE in BH data (0.90 ± 0.40 vs. 0.64 ± 0.19 mm, p = 0.005), FB data (1.21 ± 0.65 vs. 0.63 ± 0.10 mm, p < 0.001), and FB + NAV data (0.81 ± 0.21 vs. 0.63 ± 0.08 mm, p < 0.001). Improved reproducibility (4TE: 5.3 ± 2.5 ms vs. 4.0 ± 1.5 ms, p = 0.016; 20TE: 3.9 ± 2.3 ms vs. 2.2 ± 0.5 ms, p = 0.002), reduced spatial variability (4TE: 12.8 ± 3.5 ms vs. 10.3 ± 2.5 ms, p < 0.001; 20TE: 9.7 ± 3.5 ms vs. 7.5 ± 1.4 ms) and improved subjective score of T2 map quality (3.43 ± 0.79 vs. 3.69 ± 0.55, p < 0.001) were obtained using ARCTIC.

Conclusions: The ARCTIC technique substantially reduces spatial mis-alignment among T2-weighted images and improves the reproducibility and spatial variability of in-vivo T2 mapping.

No MeSH data available.


Related in: MedlinePlus