Guangzi Shi1, Hong Chen1, Weike Zeng1, Mengzhu Wang2, and Jun Shen1
1Radiology, Sun Yat-Sen Memorial Hospital, Sun Yat-Sen University, Guangzhou, China, 2Department of MR Scientific Marketing, Siemens Healthineers, Guangzhou, China
Synopsis
R2* derived from multi-echo Dixon imaging is a potential biomarker to differentiate malignant from benign FFLs. R2* value of malignant FLLs was significantly higher than that of the benign
FLLs. The multi-echo Dixon sequence is easy
to perform and required only a single breath-hold of 16 s to image the entire
liver, which holds a good potential for clinical application.
Introduction
Clinically, once a focal liver lesion (FLL) is
identified, it is essential to distinguish between benign and malignant lesions,
as this differentiation determines the individual’s prognosis and subsequent
treatment strategy[1]. R2* estimation reflects the paramagnetism of the
tumor tissue[2,3], which may be used to differentiate between benign and malignant
liver lesions when the contrast agents is contraindicated.To investigate whether R2* derived from multi-echo
Dixon imaging can aid differentiating benign
from malignant focal liver lesions (FLLs) and the impact of 2D region of
interest (2D-ROI) and volume of interest (VOI) on the outcomes.Methods
We retrospectively enrolled 73 patients with 108 benign or malignant FLLs. All patients
underwent conventional abdominal magnetic resonance imaging and multi-echo
Dixon imaging. Two radiologists independently
measured the mean R2* values of lesions using 2D-ROI and VOI approaches. The
Bland–Altman plot was used to determine the interobserver agreement between R2*
measurements. Intraclass correlation coefficient (ICC) was used to determine
the reliability between the two readers. Mean R2* values were
compared between benign and malignant FFLs using the nonparametric Mann–Whitney
test. Receiver Operating
Characteristic curve analysis was used to determine the diagnostic performance
of R2* in differentiation between benign and malignant FFLs. We
compared the diagnostic performance of R2*
measured by 2D-ROI and VOI approaches.Results
The study included 30 benign and 78 malignant FLLs. The
interobserver reproducibility of R2* measurements was excellent
for the 2D-ROI (ICC = 0.994) and VOI (ICC = 0.998)
methods. Bland–Altman analysis also demonstrated excellent agreement. Mean R2* was
significantly higher for malignant than benign FFLs as measured by 2D-ROI
(P < 0.001) and VOI (P < 0.001). The AUC of
R2* measured by 2D-ROI was 0.884 at a cut-off of 25.2/s, with a sensitivity of
84.6% and specificity of 80.0% for differentiating benign from malignant FFLs. R2*
measured by VOI yielded an area under the curve (AUC) of 0.875 at a cut-off of 26.7/s
in distinguishing benign from malignant FFLs, with a sensitivity of 85.9% and
specificity of 76.7%. The AUCs of R2* were not significantly different between the 2D-ROI and
VOI methods.Conclusion
R2* derived from multi-echo Dixon imaging whether by
2D-ROI or VOI can aid in differentiation between benign and malignant FLLs.Acknowledgements
No acknowledgement found.References
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