Department of Ultrasound, Xinhua Hospital Affiliated to Shanghai Jiao Tong University, School of Medicine, Shanghai, China.
Clin Hemorheol Microcirc. 2024;86(1-2):51-61. doi: 10.3233/CH-238102.
To explore the technical and clinical evaluation of ultrasound-derived fat fraction (UDFF) measurement in adult patients in whom fatty liver was suspected.
In this prospective study, 41 participants were initially enrolled in our hospital between October 2022 and December 2022 and received UDFF assessment using Siemens ACUSON Sequoia system equipped with DAX transducer. UDFF measurement was performed three times to obtain UDFF values from each imaging location (V hepatic segment and VIII hepatic segment) per participant, and the depth (skin-to-capsule distance) was automatically measured. The echogenicity of liver tissue in B mode ultrasound (BMUS) was compared to the normal kidney tissue, and fatty liver was graded as mild (Grade 1), moderate (Grade 2), and severe (Grade 3). The median of the acquired overall median UDFF values was used for statistical analysis. All ultrasound examinations were performed by one of two radiologists (with 20 and 10 years of liver ultrasound imaging experience).
Finally, UDFF measurement was successfully performed on 38 participants to obtain valid values, including 21 men with a median age of 40.0 years (interquartile range [IQR]: 23.0 - 58.5) and 17 women with a median age of 60.0 years (IQR: 29.5 - 67.0). Fatty liver was diagnosed by BMUS features in 47.4% (18/38) participants. Among all participants, the median UDFF value was 7.0% (IQR: 4.0 - 15.6). A significant difference in UDFF values was found between participants with fatty liver and without fatty liver (U = 7.0, P < 0.001), and UDFF values elevated as the grade of the fatty liver increased (P < 0.001). The median UDFF values from the three UDFF measurements obtained during each ultrasound examination showed excellent agreement (ICC = 0.882 [95% confidence interval: 0.833 - 0.919]). The Spearman correlation of UDFF values in different depths was moderate, with a rs value of 0.546 (P < 0.001). No significant differences in UDFF values were found between V hepatic segment and VIII hepatic segment (U = 684.5, P = 0.697).
UDFF provides a novel non-invasive imaging tool for hepatic steatosis assessment with excellent feasibility.
探讨超声衍生脂肪分数（UDFF）测量技术在疑似脂肪肝的成年患者中的临床评估。
本前瞻性研究于 2022 年 10 月至 12 月期间在我院纳入 41 名参与者，使用配备 DAX 换能器的西门子 ACUSON Sequoia 系统进行 UDFF 评估。对每位参与者的每个成像部位（V 肝段和 VIII 肝段）进行三次 UDFF 测量，以获得 UDFF 值，并自动测量深度（皮肤-包膜距离）。B 型超声（BMUS）中肝组织的回声与正常肾脏组织进行比较，脂肪肝分为轻度（1 级）、中度（2 级）和重度（3 级）。采用获取的整体中位数 UDFF 值的中位数进行统计分析。所有超声检查均由两名放射科医生之一（具有 20 年和 10 年肝脏超声成像经验）进行。
最终，对 38 名参与者成功进行了 UDFF 测量，获得了有效值，其中 21 名男性，中位年龄为 40.0 岁（四分位距 [IQR]：23.0-58.5），17 名女性，中位年龄为 60.0 岁（IQR：29.5-67.0）。BMUS 特征诊断 47.4%（18/38）的参与者患有脂肪肝。所有参与者的中位 UDFF 值为 7.0%（IQR：4.0-15.6）。有脂肪肝和无脂肪肝的参与者之间的 UDFF 值存在显著差异（U=7.0，P<0.001），且随着脂肪肝程度的增加 UDFF 值升高（P<0.001）。每次超声检查中三次 UDFF 测量获得的中位 UDFF 值显示出极好的一致性（ICC=0.882[95%置信区间：0.833-0.919]）。不同深度 UDFF 值的 Spearman 相关系数为中度，rs 值为 0.546（P<0.001）。V 肝段和 VIII 肝段的 UDFF 值无显著差异（U=684.5，P=0.697）。
UDFF 为评估肝脂肪变性提供了一种新的、可行的非侵入性成像工具。
