From the Radiology R&D (Medical Affairs).
MR and CT Contrast Media Research, Bayer AG, Berlin, Germany.
Invest Radiol. 2020 Jun;55(6):367-373. doi: 10.1097/RLI.0000000000000645.
The signal enhancement (SE) and enhancement kinetics of gadolinium-based contrast agents (GBCAs) in T1-weighted magnetic resonance (MR) images depend on the relaxivity of the GBCA and its pharmacokinetic profile. This in vivo study systematically compared the SE (technical efficacy) and the enhancement kinetics of the 3 macrocyclic GBCAs gadobutrol, gadoteridol, and gadoterate meglumine in various body regions.
A total of 15 healthy male white New Zealand rabbits were randomly divided into 3 groups (n = 5/group). The GBCAs were injected intravenously (0.1 mmol/kg body weight) and signal intensities from multiphase T1-weighted MR images (1.5 T; volumetric interpolated breath-hold examination (VIBE); repetition time/echo time/α: 4.74 milliseconds/2.38 milliseconds/10°) before and up to approximately 23 minutes after contrast injection were determined in the brain, tongue, submandibular gland, liver, spleen, prostate, muscle, and blood/aorta). Thirty minutes after injection, the animals were sacrificed and Gadolinium (Gd) concentrations were determined in the above-mentioned tissue samples by inductively coupled plasma optical emission spectrometry. Gadolinium tissue concentrations were correlated with the respective SE measurements in each tissue.
The time course of SE, representing the pharmacokinetic profile of the GBCA, was similar for all 3 agents in all tissues. The magnitude of SE was, however, tissue dependent and consistently higher for gadobutrol (P < 0.05 in all tissues but brain). No significant difference in the magnitude of SE was found between gadoteridol and gadoterate meglumine. The inductively coupled plasma optical emission spectrometry analysis revealed no differences in Gd-tissue concentrations between the GBCAs. A linear correlation was observed between SE and the respective Gd concentrations for all 3 GBCAs. A significantly higher enhancement efficacy, that is, SE per Gd concentration, was observed for gadobutrol.
Gadobutrol-enhanced MR imaging showed greater SE compared with gadoteridol and gadoterate meglumine, whereas the SE kinetics were similar among the 3 GBCAs. For all 3 GBCAs, the SE was independent of the body region.
基于钆基对比剂（GBCA）的弛豫率及其药代动力学特征，T1 加权磁共振（MR）图像中的信号增强（SE）和增强动力学各不相同。本体内研究系统比较了 3 种大环 GBCA（钆布醇、钆特醇和钆喷酸葡胺）在不同身体部位的 SE（技术功效）和增强动力学。
共 15 只健康雄性新西兰白兔随机分为 3 组（每组 5 只）。GBCA 经静脉注射（0.1mmol/kg 体重），在注射后直至约 23 分钟内，通过多期 T1 加权 MR 图像（1.5T；容积内插屏气检查（VIBE）；重复时间/回波时间/α：4.74ms/2.38ms/10°）测量脑、舌、颌下腺、肝、脾、前列腺、肌肉和血/主动脉的信号强度。注射后 30 分钟处死动物，采用电感耦合等离子体发射光谱法测定上述组织样本中的钆浓度。将组织中的钆浓度与相应的 SE 测量值进行相关性分析。
SE 的时间过程代表了 GBCA 的药代动力学特征，在所有组织中 3 种药物均相似。然而，SE 的幅度与组织有关，并且在所有组织中（脑除外），钆布醇的幅度均显著更高（P<0.05）。在 SE 幅度方面，钆特醇和钆喷酸葡胺之间无显著差异。电感耦合等离子体发射光谱分析显示 3 种 GBCA 之间的 Gd 组织浓度无差异。所有 3 种 GBCA 均观察到 SE 与相应的 Gd 浓度之间呈线性相关。与钆特醇和钆喷酸葡胺相比，钆布醇的增强效果（即每 Gd 浓度的 SE）更高。
与钆特醇和钆喷酸葡胺相比，钆布醇增强磁共振成像的 SE 更高，而 3 种 GBCA 的 SE 动力学相似。对于所有 3 种 GBCA，SE 与身体部位无关。
