Department of Radiology and Research Institute of Radiological Science, Severance Children's Hospital, Yonsei University College of Medicine, 50-1Yonsei-ro, Seodaemun-gu, Seoul, 03722, South Korea.
Severance Pediatric Liver Disease Research Group, Severance Children's Hospital, Yonsei University College of Medicine, Seoul, South Korea.
BMC Pediatr. 2019 Apr 15;19(1):112. doi: 10.1186/s12887-019-1485-8.
Controlled attenuation parameter (CAP) is a recently introduced, non-invasive and quantitative method to evaluate hepatic steatosis demonstrated in adults, but limited in obesity and not well evaluated in children. The aim of this study was to investigate the diagnostic performance for assessing hepatic steatosis grades using CAP in children based on MR proton density fat fraction (PDFF).
Children evaluated for non-alcoholic fatty liver disease (NAFLD) who were assessed for PDFF and CAP were enrolled retrospectively. Hepatic steatosis grades 0-3 were classified according to PDFF using cutoff values of 6, 17.5, and 23.3%. Subgroup analyses were performed in non-obese and obese groups using the 95th percentile body mass index (BMI) as a cutoff and BMI30 group when BMI > 30 kg/m. Pearson's correlations between variables were also analyzed.
In a total of 86 children, there were 53 in the obese group including 17 of the BMI30 group. CAP demonstrated 98.7% sensitivity and 80% specificity for diagnosing grades 1-3 vs. grade 0 using a cutoff value of 241 dB/m (area under the curve = 0.941, p < 0.001). The diagnostic performance for higher steatosis grades was suboptimal. CAP correlated with abdominal wall thickness in both obese (r = 0.549, p = 0.001) and non-obese (r = 0.386, p = 0.004) groups and did not correlate with PDFF in BMI30 group.
In children with NAFLD, CAP showed excellent diagnostic performance for differentiating presence and absence of hepatic steatosis using a cutoff value of 241 dB/m. However, CAP was limited in evaluating grades of steatosis, especially in children with BMI > 30 kg/m.
受控衰减参数（CAP）是一种最近引入的、非侵入性的定量方法，可用于评估成年人的肝脂肪变性，但在肥胖症中受限，并且在儿童中的评估效果不佳。本研究旨在通过磁共振质子密度脂肪分数（PDFF）研究 CAP 评估儿童肝脂肪变性程度的诊断性能。
回顾性纳入评估非酒精性脂肪性肝病（NAFLD）并接受 PDFF 和 CAP 评估的儿童。根据 PDFF 将肝脂肪变性程度分为 0-3 级，使用的截断值分别为 6、17.5 和 23.3%。使用 95%体质量指数（BMI）作为截断值和 BMI＞30kg/m2 时 BMI30 组进行非肥胖组和肥胖组的亚组分析。还分析了变量之间的 Pearson 相关性。
在总共 86 名儿童中，肥胖组 53 名，包括 BMI30 组 17 名。使用 241dB/m 的截断值，CAP 诊断 1-3 级与 0 级的敏感度为 98.7%，特异度为 80%（曲线下面积 0.941，p＜0.001）。对于更高程度的肝脂肪变性，诊断性能欠佳。CAP 在肥胖组（r=0.549，p=0.001）和非肥胖组（r=0.386，p=0.004）中均与腹壁厚度相关，而与 BMI30 组的 PDFF 不相关。
在患有 NAFLD 的儿童中，使用 241dB/m 的截断值，CAP 对区分是否存在肝脂肪变性具有出色的诊断性能。然而，CAP 对评估脂肪变性程度的作用有限，尤其是在 BMI＞30kg/m2 的儿童中。
