Computed tomography (CT)-derived body metrics such as skeletal muscle index (SMI), psoas muscle index (PMI), and subcutaneous fat area index (ScFI) are measurable components of sarcopenia, frailty, and nutrition. While these body metrics are advocated in adults for predicting postoperative outcomes after liver transplantation (LT), little is known about their value in pediatric populations. This study assessed the relation between preoperative CT-based body metrics and postoperative short-term outcomes in pediatric LT recipients. Patients aged 0-18 years who underwent a primary LT were retrospectively included (n = 101; median age 0.5 years; range 0.2-17.1). SMI, PMI, and ScFI were derived from preoperative axial CT slices. Postoperative outcomes and complications within 90 days were correlated with the CT-based body metrics. To classify postoperative infections, the Clavien-Dindo (CD) classification was used. Subgroup analyses were performed for age groups (<1, 1-10, and >10 years old). An optimal threshold for test performance was defined using Youden’s J-statistic and receiver operating characteristic curve as appropriate. ScFI was significantly (P = 0.001) correlated with moderate to severe postoperative infections (CD grade 3-5) in children aged <1 year, with the optimal ScFI threshold being ≤27.1 cm²/m² (sensitivity 80.4% and specificity 77.8%). A weak negative correlation between SMI and the total duration of hospital stay (R = −0.3; P = 0.01) and intensive care unit (ICU) stay (R = −0.3; P = 0.01) was observed in children aged <1 year. No other associations between CT-based body metrics and postoperative outcomes were shown. In children aged <1 year with cirrhotic liver disease undergoing LT, preoperative CT-based body metrics were correlated with moderate to severe postoperative infections (ScFI) and with longer duration of hospital and ICU stay (SMI), and thus can be considered important tools for pre-LT risk assessment.

中文翻译：

---

基于术前计算机断层扫描的身体指标在小儿肝移植受者术后并发症中的应用

计算机断层扫描 (CT) 衍生的身体指标，如骨骼肌指数 (SMI)、腰大肌指数 (PMI) 和皮下脂肪面积指数 (ScFI)，是肌肉减少症、虚弱和营养的可测量组成部分。虽然这些身体指标在成人中被提倡用于预测肝移植 (LT) 后的术后结果，但人们对其在儿科人群中的价值知之甚少。本研究评估了儿科 LT 接受者术前基于 CT 的身体指标与术后短期结果之间的关系。回顾性纳入接受过初次 LT 的 0-18 岁患者（n = 101；中位年龄 0.5 岁；范围 0.2-17.1）。SMI、PMI 和 ScFI 来自术前轴位 CT 切片。90 天内的术后结果和并发症与基于 CT 的身体指标相关。为了对术后感染进行分类，使用了 Clavien-Dindo (CD) 分类法。对年龄组（<1 岁、1-10 岁和>10 岁）进行了亚组分析。使用 Youden 定义了测试性能的最佳阈值J-统计量和接受者操作特征曲线（视情况而定）。ScFI 与 <1 岁儿童的中度至重度术后感染（CD 3-5 级）显着相关（P  = 0.001），最佳 ScFI 阈值≤27.1 cm 2 ^/ m ²（敏感性 80.4%，特异性 77.8%） ). SMI 与总住院时间 ( R  = -0.3; P  = 0.01) 和重症监护病房 (ICU) 住院时间 ( R  = -0.3; P)呈弱负相关 = 0.01) 在 <1 岁的儿童中观察到。没有显示基于 CT 的身体指标与术后结果之间的其他关联。在接受 LT 的 1 岁以下肝硬化儿童中，基于 CT 的术前身体指标与中度至重度术后感染 (ScFI) 以及较长的住院时间和 ICU 停留时间 (SMI) 相关，因此可被视为重要工具用于 LT 前风险评估。