Multiple b value diffusion-weighted MRI of liver: A novel respiratory frequency-modulated continuous-wave radar-trigger technique and comparison with free-breathing technique

Kai Liu; Caizhong Chen; Tingting Shen; Xixi Wen; Mengsu Zeng; Pengju Xu

doi:10.1016/j.mri.2024.110312

Multiple b value diffusion-weighted MRI of liver: A novel respiratory frequency-modulated continuous-wave radar-trigger technique and comparison with free-breathing technique

Magn Reson Imaging. 2024 Dec 16:117:110312. doi: 10.1016/j.mri.2024.110312. Online ahead of print.

Authors

Kai Liu¹, Caizhong Chen², Tingting Shen³, Xixi Wen⁴, Mengsu Zeng⁵, Pengju Xu⁶

Affiliations

¹ Department of Radiology, Zhongshan Hospital, Fudan University, Shanghai Institute of Medical Imaging, China. Electronic address: [email protected].
² Department of Radiology, Zhongshan Hospital, Fudan University, Shanghai Institute of Medical Imaging, China. Electronic address: [email protected].
³ Department of Radiology, Zhongshan Hospital, Fudan University, Shanghai Institute of Medical Imaging, China. Electronic address: [email protected].
⁴ Shanghai United Imaging Healthcare Co., Ltd., Shanghai, China. Electronic address: [email protected].
⁵ Department of Radiology, Zhongshan Hospital, Fudan University, Shanghai Institute of Medical Imaging, China.
⁶ Department of Radiology, Zhongshan Hospital, Fudan University, Shanghai Institute of Medical Imaging, China. Electronic address: [email protected].

PMID: 39694121
DOI: 10.1016/j.mri.2024.110312

Abstract

Objective: The aim of this study was to evaluate a novel respiratory frequency-modulated continuous-wave radar-trigger (FT) technique for multiple -b-value diffusion-weighted imaging (DWI) of liver and compare it with conventional free breathing (FB) DWI technique.

Material and methods: 39 patients with focal liver lesions underwent both frequency-modulated continuous-wave radar-trigger (FT) and conventional free-breathing (FB) multi-b-value diffusion-weighted imaging (DWI,b = 0,50,400,800 s/mm²⁾. Two abdominal radiologists independently assessed the quality of liver DWI images obtained using both techniques, measured and compared liver signal-to-noise ratio (SNR) and contrast-to-noise ratio (CNR) at different b-values, as well as apparent diffusion coefficient (ADC) values calculated from all b-values.

Results: In terms of image quality, the FT technique is superior to the conventional FB technique, with overall image quality scores (Reader 1, 3.56 ± 0.50 and Reader 2, 3.59 ± 0.55)vs (Reader 1, 2.90 ± 0.75 and Reader 2, 2.97 ± 0.71), respectively. The liver SNR (at b-values of 50,400,and 800 s/mm²) obtained by FT was (138.5 ± 43.48, 96.67 ± 31.95, 71.54 ± 22.03), respectively, which was significantly higher than that obtained by conventional FB (110.90 ± 39.28, 80.86 ± 29.13, 60.43 ± 18.61, P < 0.05). The lesion CNR with FT was significantly higher than that with conventional FB (258.99 ± 151.38 vs 174.60 ± 99.90; 164.56 ± 87.25 vs 111.12 ± 42.43; 118.83 ± 68.76 vs 76.01 ± 35.48, P < 0.001). There was no significant difference in ADC values of liver and lesions between the two techniques: ADCliver-L and ADCliver-R: (FT 1479.3 ± 270.0 vs FB 1529.3 ± 275.5 and FT 1219.6 ± 127.4 vs FB 1248.7 ± 168.2, P > 0.05); ADC lesion:FT(969.0 ± 261.3) vs FB (1017.5 ± 240.4, P > 0.05).

Conclusion: For multi-b-value liver diffusion-weighted imaging, FT technique has higher image quality and better lesion visibility than conventional FB technique and there is no significant difference in ADC values of liver and lesions between the two techniques.

Keywords: Comparison; Diffusion-weighted imaging; Free-breathing; Frequency-modulated continuous-wave radar-trigger; Multi-b value.