From the Department of Neuroradiology, University of Heidelberg Medical Center, Im Neuenheimer Feld 400, 69120 Heidelberg, Germany (A.R., L.D.W., O.E., S.B., P.K., S.H., M.B.); Department of Radiology, German Cancer Research Center (DKFZ), Heidelberg, Germany (A.R., H.P.S.); Department of Psychology, University of Mannheim, Mannheim, Germany (P.J.K.); and Neurology Clinic, University of Heidelberg, Heidelberg, Germany (W.W.).
Radiology. 2015 Jun;275(3):783-91. doi: 10.1148/radiol.2015150337. Epub 2015 Apr 6.
To compare changes in signal intensity (SI) ratios of the dentate nucleus (DN) and the globus pallidus (GP) to those of other structures on unenhanced T1-weighted magnetic resonance (MR) images between linear and macrocyclic gadolinium-based contrast agents (GBCAs).
The study was approved by the ethical committee of the University of Heidelberg (reference no. S-324/2014). Owing to the retrospective character of the study, the ethical committee did not require any written informed consent. Two groups of 50 patients who underwent at least six consecutive MR imaging examinations with the exclusive use of either a linear GBCA (gadopentetate dimeglumine) or a macrocyclic GBCA (gadoterate meglumine) were analyzed retrospectively. The difference in mean SI ratios of DN to pons and GP to thalamus on unenhanced T1-weighted images from the last and first examinations was calculated. One-sample and independent-sample t tests were used to assess the difference in SI ratios for both groups, and regression analysis was performed to account for potential confounders.
The SI ratio difference in the linear group was greater than 0 (mean DN difference ± standard deviation, 0.0407 ± 0.0398 [P < .001]; GP, 0.0287 ± 0.0275 [P < .001]) and significantly larger (DN, P < .001 and standardized difference of 1.16; GP, P < .001 and standardized difference of 0.81) than that in the macrocyclic group, which did not differ from 0 (DN, 0.0016 ± 0.0266 [P = .680]; GP, 0.0031 ± 0.0354 [P = .538]). The SI ratio difference between the last and first examinations for the DN remained significantly different between the two groups in the regression analysis (P < .001).
This study indicates that an SI increase in the DN and GP on T1-weighted images is caused by serial application of the linear GBCA gadopentetate dimeglumine but not by the macrocyclic GBCA gadoterate meglumine. Clinical implications of this observation remain unclear.
比较线性和大环钆基对比剂（GBCA）增强前后 T1 加权磁共振（MR）图像上齿状核（DN）和苍白球（GP）与其他结构的信号强度（SI）比值的变化。
本研究得到海德堡大学伦理委员会的批准（参考号 S-324/2014）。由于研究的回顾性特征，伦理委员会不需要任何书面知情同意书。回顾性分析了两组各 50 例患者，这些患者至少连续进行了 6 次 MR 检查，仅使用线性 GBCA（钆喷酸二甲葡胺）或大环 GBCA（钆特酸葡甲胺）。计算最后和第一次检查时未增强 T1 加权图像上 DN 与脑桥和 GP 与丘脑的平均 SI 比值差异。采用单样本和独立样本 t 检验比较两组的 SI 比值差异，并进行回归分析以考虑潜在的混杂因素。
线性组的 SI 比值差异大于 0（平均 DN 差异±标准偏差，0.0407±0.0398[P<.001]；GP，0.0287±0.0275[P<.001]），且明显大于大环组（DN，P<.001 和标准化差异为 1.16；GP，P<.001 和标准化差异为 0.81），大环组的 SI 比值差异与 0 无差异（DN，0.0016±0.0266[P=.680]；GP，0.0031±0.0354[P=.538]）。回归分析显示，DN 的最后和第一次检查之间的 SI 比值差异在两组之间仍有显著差异（P<.001）。
本研究表明，T1 加权图像上 DN 和 GP 的 SI 增加是由线性 GBCA 钆喷酸二甲葡胺的连续应用引起的，而不是由大环 GBCA 钆特酸葡甲胺引起的。这种观察结果的临床意义尚不清楚。
