Department of Radiology, University of Groningen, University Medical Center Groningen, PO Box 30 001, 9700 RB, Groningen, The Netherlands.
Department of Hepatobiliary Surgery and Liver Transplantation, University of Groningen, University Medical Center Groningen, Groningen, The Netherlands.
Eur Radiol. 2023 Sep;33(9):6404-6413. doi: 10.1007/s00330-023-09522-2. Epub 2023 Mar 17.
Doppler ultrasound (DUS) is the main imaging modality to evaluate vascular complications of pediatric liver transplants (LT). The current study aimed to determine reference values and their change over time.
A consecutive cohort of pediatric patients undergoing an LT were retrospectively included between 2015 and 2020. Timepoints for standardized DUS were intra-operative and postoperative (day 0), days 1-7, months 1 and 3, and years 1 and 2. DUS measurements of the hepatic artery (HA), portal vein (PV), and hepatic vein(s) (HV) were included if there were no complications during 2 years follow-up. Measurements consisted of: peak systolic velocity (PSV) and resistive index (RI) for the HA, PSV for the PV, and venous pulsatility index (VPI) for the HV. Generalized estimating equations were used to analyze change over time.
One hundred twelve pediatric patients with 123 LTs were included (median age 3.3 years, interquartile range 0.7-10.1). Ninety-five HAs, 100 PVs, and 115 HVs without complications were included. Reference values for HA PSV and RI, PV PSV, and HV VPI were obtained for all timepoints (4043 included data points in total) and presented using 5-95 percentiles and threshold values. All reference values changed significantly over time (p = 0.032 to p < 0.001).
DUS reference values of hepatic vessels in children after LT are presented, reference values change over time with specific vessel-dependent patterns. Timepoint-specific reference values improve the interpretation of DUS values and may help to better weigh their clinical significance.
• Doppler ultrasound reference values of pediatric liver transplantations are not static but change over time. Applying the correct reference values for the specific timepoint may further improve the interpretation of the measurements. • The pattern of change over time of Doppler ultrasound measurements differs between the hepatic vessel and measurement; knowledge of these patterns may help radiologists to better understand normal postoperative hemodynamic changes.
多普勒超声（DUS）是评估儿科肝移植（LT）血管并发症的主要成像方式。本研究旨在确定参考值及其随时间的变化。
回顾性纳入 2015 年至 2020 年间连续接受 LT 的儿科患者队列。标准化 DUS 的时间点包括手术中和术后（第 0 天）、第 1-7 天、第 1、3 个月和第 1、2 年。如果在 2 年随访期间没有并发症，则纳入肝动脉（HA）、门静脉（PV）和肝静脉（HV）的 DUS 测量值。测量包括：HA 的峰值收缩速度（PSV）和阻力指数（RI）、PV 的 PSV 和 HV 的静脉搏动指数（VPI）。使用广义估计方程分析随时间的变化。
共纳入 123 例 LT 的 112 例儿科患者（中位年龄 3.3 岁，四分位间距 0.7-10.1）。纳入 95 条 HA、100 条 PV 和 115 条无并发症的 HV。获得了所有时间点（总共 4043 个数据点）的 HA PSV 和 RI、PV PSV 和 HV VPI 的参考值，并使用 5-95 百分位数和阈值值表示。所有参考值随时间显著变化（p = 0.032 至 p < 0.001）。
本研究提供了 LT 后儿童肝血管的 DUS 参考值，参考值随时间变化，具有特定的血管依赖性模式。特定时间点的参考值可提高 DUS 值的解释，并有助于更好地权衡其临床意义。
• 儿科肝移植的多普勒超声参考值不是静态的，而是随时间变化的。应用特定时间点的正确参考值可能会进一步提高测量结果的解释。
• 多普勒超声测量值随时间变化的模式在肝血管和测量之间有所不同；了解这些模式可能有助于放射科医生更好地理解术后正常的血液动力学变化。
