Next Article in Journal
Peritumoral Brain Edema in Relation to Tumor Size Is a Variable That Influences the Risk of Recurrence in Intracranial Meningiomas
Previous Article in Journal
Myocarditis Following COVID-19 Vaccination: Cardiac Imaging Findings in 118 Studies
 
 
Article

B0 Correction for 3T Amide Proton Transfer (APT) MRI Using a Simplified Two-Pool Lorentzian Model of Symmetric Water and Asymmetric Solutes

1
Xi’an Key Laboratory of Radiomics and Intelligent Perception, School of Information Sciences and Technology, Northwest University, Xi’an 710069, China
2
Department of Radiology, Beijing Tsinghua Changgung Hospital, Beijing 102218, China
3
Center for Biomedical Imaging Research, Department of Biomedical Engineering, Tsinghua University, Beijing 100084, China
*
Author to whom correspondence should be addressed.
These authors contributed equally to this work.
Academic Editor: Emilio Quaia
Tomography 2022, 8(4), 1974-1986; https://doi.org/10.3390/tomography8040165
Received: 4 May 2022 / Revised: 17 July 2022 / Accepted: 27 July 2022 / Published: 1 August 2022
(This article belongs to the Section Brain Imaging)
Amide proton transfer (APT)-weighted MRI is a promising molecular imaging technique that has been employed in clinic for detection and grading of brain tumors. MTRasym, the quantification method of APT, is easily influenced by B0 inhomogeneity and causes artifacts. Current model-free interpolation methods have enabled moderate B0 correction for middle offsets, but have performed poorly at limbic offsets. To address this shortcoming, we proposed a practical B0 correction approach that is suitable under time-limited sparse acquisition scenarios and for B1 ≥ 1 μT under 3T. In this study, this approach employed a simplified Lorentzian model containing only two pools of symmetric water and asymmetric solutes, to describe the Z-spectral shape with wide and ‘invisible’ CEST peaks. The B0 correction was then performed on the basis of the fitted two-pool Lorentzian lines, instead of using conventional model-free interpolation. The approach was firstly evaluated on densely sampled Z-spectra data by using the spline interpolation of all acquired 16 offsets as the gold standard. When only six offsets were available for B0 correction, our method outperformed conventional methods. In particular, the errors at limbic offsets were significantly reduced (n = 8, p < 0.01). Secondly, our method was assessed on the six-offset APT data of nine brain tumor patients. Our MTRasym (3.5 ppm), using the two-pool model, displayed a similar contrast to the vendor-provided B0-orrected MTRasym (3.5 ppm). While the vendor failed in correcting B0 at 4.3 and 2.7 ppm for a large portion of voxels, our method enabled well differentiation of B0 artifacts from tumors. In conclusion, the proposed approach could alleviate analysis errors caused by B0 inhomogeneity, which is useful for facilitating the comprehensive metabolic analysis of brain tumors. View Full-Text
Keywords: amide proton transfer (APT) MRI; B0 inhomogeneity correction; brain tumors; Lorentzian fitting; chemical exchange saturation transfer (CEST) MRI amide proton transfer (APT) MRI; B0 inhomogeneity correction; brain tumors; Lorentzian fitting; chemical exchange saturation transfer (CEST) MRI
Show Figures

Figure 1

MDPI and ACS Style

Chen, Y.; Dang, X.; Zhao, B.; Zheng, Z.; He, X.; Song, X. B0 Correction for 3T Amide Proton Transfer (APT) MRI Using a Simplified Two-Pool Lorentzian Model of Symmetric Water and Asymmetric Solutes. Tomography 2022, 8, 1974-1986. https://doi.org/10.3390/tomography8040165

AMA Style

Chen Y, Dang X, Zhao B, Zheng Z, He X, Song X. B0 Correction for 3T Amide Proton Transfer (APT) MRI Using a Simplified Two-Pool Lorentzian Model of Symmetric Water and Asymmetric Solutes. Tomography. 2022; 8(4):1974-1986. https://doi.org/10.3390/tomography8040165

Chicago/Turabian Style

Chen, Yibing, Xujian Dang, Benqi Zhao, Zhuozhao Zheng, Xiaowei He, and Xiaolei Song. 2022. "B0 Correction for 3T Amide Proton Transfer (APT) MRI Using a Simplified Two-Pool Lorentzian Model of Symmetric Water and Asymmetric Solutes" Tomography 8, no. 4: 1974-1986. https://doi.org/10.3390/tomography8040165

Find Other Styles

Article Access Map by Country/Region

1
Back to TopTop