CT energy spectral parameters of creeping fat in Crohn's disease and correlation with inflammatory activity

Xianchu Li; Wei Wu; Yan Yuan; Zhiming Zhu; Xiaowei Liu; Desheng Xiao; Xueying Long

doi:10.1186/s13244-023-01592-6

CT energy spectral parameters of creeping fat in Crohn's disease and correlation with inflammatory activity

Insights Imaging. 2024 Jan 17;15(1):10. doi: 10.1186/s13244-023-01592-6.

Authors

Xianchu Li^{1

2}, Wei Wu^{3

4}, Yan Yuan², Zhiming Zhu², Xiaowei Liu⁵, Desheng Xiao⁶, Xueying Long^{7

8}

Affiliations

¹ Department of Radiology, The Second Affiliated Hospital, Hengyang Medical School, University of South China, Hengyang, China.
² Department of Radiology, Xiangya Hospital, Central South University, 87 Xiangya Road, Changsha, 410008, China.
³ Department of General Surgery, Xiangya Hospital, Central South University, Changsha, China.
⁴ National Clinical Research Center for Geriatric Disorders, Xiangya Hospital, Central South University, Changsha, China.
⁵ Department of Gastroenterology, Xiangya Hospital, Central South University, Changsha, China.
⁶ Department of Pathology, Xiangya Hospital, Central South University, Changsha, China.
⁷ Department of Radiology, Xiangya Hospital, Central South University, 87 Xiangya Road, Changsha, 410008, China. longxueying@csu.edu.cn.
⁸ National Clinical Research Center for Geriatric Disorders, Xiangya Hospital, Central South University, Changsha, China. longxueying@csu.edu.cn.

Abstract

Objectives: Creeping fat is a kind of unique abnormal mesenteric tissue at the sites of diseased bowel of Crohn's disease. By using dual-energy CT enterography, this study aimed to evaluate the feasibility of spectral parameters in the quantitative analysis of mesenteric adipose tissue or creeping fat.

Methods: In this study, patients with known or suspected Crohn's disease who underwent dual-energy CT enterography from March 1, 2019, to March 31, 2021, were enrolled. Among them, 40 patients with surgery and pathology-proven creeping fat were selected as the creeping fat Crohn's disease group, and 40 normal patients were selected as the control group. The quantitative spectral parameters including the slope of the Hounsfield unit curve, normalised fat-water concentration, normalised fat-iodine concentration, and normalised fat volume fraction at the enteric phases were obtained. Mann-Whitney U test, Kruskal-Wallis H test, and receiver operating characteristic curve analysis were applied to compare quantitative parameters among various groups.

Results: A significant difference was observed in the slope of the Hounsfield unit curve, normalised fat-water concentration, normalised fat-iodine concentration, and normalised fat volume fraction between mesenteric adipose tissue and creeping fat with Crohn's disease at the enteric phase (all p < 0.001). The slope of the Hounsfield unit curve of creeping fat at the enteric phase had a better capability to distinguish inactive and active Crohn's disease (AUC = 0.93, p < 0.001).

Conclusion: Dual-energy CT enterography with quantitative spectral parameters is a potentially novel noninvasive tool for evaluating creeping fat in Crohn's disease.

Critical relevance statement: Energy spectral parameters of creeping fat in Crohn's disease are significantly different from normal mesenteric adipose tissues and are correlated with inflammatory activity.

Key points: • Dual-energy CT enterography allows quantitatively assessing creeping fat with spectral parameters. • The creeping fat has distinct spectral parameters to normal mesenteric adipose. • The spectral parameters accurately differentiate active and inactive Crohn's disease.

Keywords: CT enterography; Creeping fat; Crohn’s disease; Dual-energy; Mesenteric adipose tissue.

Grants and funding

GEHC-CT-CFP-2018-01/GE Global Research