钆哌醇与钆贝葡胺体外弛豫率及肝脑成像随机交叉研究
本研究通过体外弛豫率测量和随机个体内交叉设计，比较钆哌醇与钆贝葡胺的r1、r2、r2*弛豫率，并在动态肝脏MRI和脑灌注DSC MRI中评估剂量依赖性效应。结果显示钆哌醇体外弛豫率更高；0.05mmol/kg钆哌醇腹部增强与0.1mmol/kg钆贝葡胺相当，而0.1mmol/kg钆哌醇信号更高；DSC灌注中0.05mmol/kg钆哌醇AIF峰值和AUC显著降低，0.1mmol/kg则与钆贝葡胺匹配。
要点
- 钆哌醇体外r1、r2、r2*弛豫率均高于钆贝葡胺，呈场强和介质依赖性线性关系。
- 0.05mmol/kg钆哌醇腹部T1增强效果与0.1mmol/kg钆贝葡胺相当，支持剂量减半。
- DSC脑灌注推荐0.1mmol/kg钆哌醇，0.05mmol/kg会显著降低AIF峰值和AUC。
核心结论
- 0.05mmol/kg钆哌醇可维持T1加权腹部成像性能，支持剂量降低；更高剂量增强信号和磁化率效应。
- 钆哌醇最佳剂量取决于应用场景，尤其DSC灌注MRI需更高剂量。
研究设计与样本
- 体外弛豫率在生理盐水、血浆和全血中于1.5T和3.0T下测量，覆盖临床相关浓度。
- 随机个体内交叉设计，受试者接受3次MRI检查：0.05mmol/kg钆哌醇、0.1mmol/kg钆哌醇、0.1mmol/kg钆贝葡胺，间隔≥28天。
- 肝脏成像纳入10例局灶性结节性增生参与者（7女；年龄20至81岁），DSC灌注成像纳入10名健康参与者（1女9男；年龄35至77岁），共完成60次MRI检查。
关键影像表现/征象
- 体外实验显示所有对比剂和介质呈场强和介质依赖性线性弛豫率（R²>0.98），钆哌醇r1、r2、r2* consistently更高。
- 腹部增强：0.05mmol/kg钆哌醇与0.1mmol/kg钆贝葡胺相当，0.1mmol/kg钆哌醇产生显著更高的肝实质和血管增强。
- DSC灌注：0.05mmol/kg钆哌醇AIF峰值和AUC显著降低，0.1mmol/kg钆哌醇与钆贝葡胺接近。
- 尽管首过效应减弱，所有方案间灰质/白质rCBV比值一致性高。
临床应用与阅片要点
- 腹部T1增强可考虑钆哌醇0.05mmol/kg以实现剂量减半，但需注意更高剂量可提升肝实质和血管信号。
- DSC脑灌注成像应使用钆哌醇0.1mmol/kg以匹配钆贝葡胺的AIF指标，避免0.05mmol/kg导致AIF峰值和AUC低估。
- 解读rCBV比值时，即使首过效应减弱，灰白质比值一致性仍较高，但需结合AIF变化综合判断。
局限性
- 肝脏成像样本量较小（10例），且为局灶性结节性增生患者，结论外推需谨慎。
- DSC灌注仅纳入10名健康参与者，性别分布不均衡（1女9男）。
- 研究为个体内交叉设计，但未报告盲法及随机化细节。
以上解读依据论文摘要（全文未开放获取或许可不允许翻译转载）。
英文原文（摘要）· 点击展开
OBJECTIVES: High-relaxivity macrocyclic gadolinium-based contrast agents (GBCAs) have been introduced to reduce the administered gadolinium dose while maintaining high diagnostic performance. Gadopiclenol exhibits higher intrinsic relaxivity than conventional extracellular agents, but comprehensive evaluation of longitudinal and transverse relaxivity across biologically relevant media and in vivo applications remains limited. The purpose was to compare r1, r2, and r2* relaxivity of gadopiclenol and gadobenate dimeglumine, and to assess dose-dependent in vivo effects in dynamic liver MRI and dynamic susceptibility contrast (DSC) MRI of brain perfusion using a randomized intraindividual crossover design.
METHODS: Relaxivity was measured in saline, plasma, and whole blood at 1.5T and 3.0T across clinically relevant concentrations. In vivo, participants underwent 3 MRI examinations in a randomized crossover design using 0.05mmol/kg gadopiclenol, 0.1mmol/kg gadopiclenol, and 0.1mmol/kg gadobenate dimeglumine, each separated by ≥28 days. Liver imaging assessed signal enhancement, relative contrast and between-visit residual GBCA effects. DSC perfusion evaluated arterial input function (AIF) metrics and gray-to-white matter relative cerebral blood volume (GM/WM rCBV) ratios.
RESULTS: Phantom experiments demonstrated field-dependent and medium-dependent linear relaxivity for all agents and media (R²>0.98), with consistently higher r1, r2, and r2* for gadopiclenol. Liver imaging was performed in 10 participants with focal nodular hyperplasia (7 women; age 20 to 81 y); DSC perfusion imaging was acquired in 10 healthy participants (1 woman, 9 men; age 35 to 77 y). Overall, 60 MRI examinations were performed. Enhancement in the abdomen was comparable between 0.05mmol/kg gadopiclenol and 0.1mmol/kg gadobenate, while 0.1mmol/kg gadopiclenol produced significantly higher liver parenchymal and vascular enhancement. In DSC perfusion imaging, AIF peak and AUC were significantly reduced with 0.05mmol/kg gadopiclenol, whereas 0.1mmol/kg gadopiclenol closely matched gadobenate dimeglumine. Agreement of GM/WM rCBV ratios was high across all protocols despite attenuated first-pass effects.
DISCUSSION: 0.05mmol/kg gadopiclenol maintains T1-weighted abdominal imaging performance, supporting dose reduction, while higher dosing enhances signal and susceptibility effects. Optimal gadopiclenol dosing appears application-dependent, particularly for DSC perfusion MRI.
引用
- Heidenreich JF, Tamada D, Rice J, et al. Relaxivity Performance of Gadopiclenol Versus Gadobenate Dimeglumine In Vitro, and Liver and Brain Imaging: A Randomized Crossover Study. Invest Radiol. 2026. PMID: 42132130. doi:10.1097/RLI.0000000000001295
供执业医师工作参考，不替代临床判断；数值与分级以指南原文为准。