Dataset Information

Confounder-corrected T₁ mapping in the liver through simultaneous estimation of T₁ , PDFF, R2* , and B1+ in a single breath-hold acquisition.

ABSTRACT:

Purpose

Quantitative volumetric T₁ mapping in the liver has the potential to aid in the detection, diagnosis, and quantification of liver fibrosis, inflammation, and spatially resolved liver function. However, accurate measurement of hepatic T₁ is confounded by the presence of fat and inhomogeneous B1+$$ {B}_1^{+} $$ excitation. Furthermore, scan time constraints related to respiratory motion require tradeoffs of reduced volumetric coverage and/or increased acquisition time. This work presents a novel 3D acquisition and estimation method for confounder-corrected T₁ measurement over the entire liver within a single breath-hold through simultaneous estimation of T₁ , fat and B1+$$ {B}_1^{+} $$ .

Theory and methods

The proposed method combines chemical shift encoded MRI and variable flip angle MRI with a B1+$$ {B}_1^{+} $$ mapping technique to enable confounder-corrected T₁ mapping. The method was evaluated theoretically and demonstrated in both phantom and in vivo acquisitions at 1.5 and 3.0T. At 1.5T, the method was evaluated both pre- and post- contrast enhancement in healthy volunteers.

Results

The proposed method demonstrated excellent linear agreement with reference inversion-recovery spin-echo based T₁ in phantom acquisitions at both 1.5 and 3.0T, with minimal bias (5.2 and 45 ms, respectively) over T₁ ranging from 200-1200 ms. In vivo results were in general agreement with reference saturation-recovery based 2D T₁ maps (SMART₁ Map, GE Healthcare).

Conclusion

The proposed 3D T₁ mapping method accounts for fat and B1+$$ {B}_1^{+} $$ confounders through simultaneous estimation of T₁ , B1+$$ {B}_1^{+} $$ , PDFF and R2*$$ {R}_2^{\ast } $$ . It demonstrates strong linear agreement with reference T₁ measurements, with low bias and high precision, and can achieve full liver coverage in a single breath-hold.

SUBMITTER: Roberts NT

PROVIDER: S-EPMC10139739 | biostudies-literature | 2023 Jun

REPOSITORIES: biostudies-literature

ACCESS DATA

Publications

Confounder-corrected T<sub>1</sub> mapping in the liver through simultaneous estimation of T<sub>1</sub> , PDFF, R 2 * , and B 1 + in a single breath-hold acquisition.

Roberts Nathan T NT Tamada Daiki D Muslu Yavuz Y Hernando Diego D Reeder Scott B SB

Magnetic resonance in medicine 20230119 6

<h4>Purpose</h4>Quantitative volumetric T<sub>1</sub> mapping in the liver has the potential to aid in the detection, diagnosis, and quantification of liver fibrosis, inflammation, and spatially resolved liver function. However, accurate measurement of hepatic T<sub>1</sub> is confounded by the presence of fat and inhomogeneous B 1 + $$ {B}_1^{+} $$ excitation. Furthermore, scan time constraints related to respiratory motion require tradeoffs of reduced volumetric coverage and/or increased a ...[more]

PMID: 36656152

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Dataset Information

Confounder-corrected T₁ mapping in the liver through simultaneous estimation of T₁ , PDFF, R2* , and B1+ in a single breath-hold acquisition.

Purpose

Theory and methods

Results

Conclusion

Publications

Confounder-corrected T<sub>1</sub> mapping in the liver through simultaneous estimation of T<sub>1</sub> , PDFF, R 2 * , and B 1 + in a single breath-hold acquisition.

Similar Datasets

OmicsDI is part of the ELIXIR infrastructure

Tweets

Dataset Information

Confounder-corrected T1 mapping in the liver through simultaneous estimation of T1 , PDFF, R2* , and B1+ in a single breath-hold acquisition.

Purpose

Theory and methods

Results

Conclusion

Publications

Confounder-corrected T<sub>1</sub> mapping in the liver through simultaneous estimation of T<sub>1</sub> , PDFF, R 2 * , and B 1 + in a single breath-hold acquisition.

Similar Datasets

OmicsDI is part of the ELIXIR infrastructure

Tweets

Confounder-corrected T₁ mapping in the liver through simultaneous estimation of T₁ , PDFF, R2* , and B1+ in a single breath-hold acquisition.