Nural Mehmet Selim, Gokce Erkan, Danaci Murat, Bayrak Ilkay Koray, Diren H Baris
Ondokuz Mayis University, Faculty of Medicine, Department of Radiology, Samsun, Turkey.
Eur J Radiol. 2008 Apr;66(1):65-74. doi: 10.1016/j.ejrad.2007.04.022. Epub 2007 Jun 6.
Gadobenate dimeglumine (Gd-BOPTA) is a liver-specific contrast agent also showing a distribution in the extracellular compartment which is recommended to be used at standard dose (0.05 mmol/kg) in magnetic resonance imaging (MRI) of liver lesions. However, its use at 0. 1mmol/kg is gradually increasing in recent clinical practice. Which dose should we use in routine MRI of liver lesions from now on? This study investigated the efficacy of Gd-BOPTA at a standard dose versus 0.1 mmol/kg dose in demonstrating diagnostic data in MRI of focal liver lesions.
The study included 47 patients with focal liver lesions. Twenty-two patients received standard dose and 25 patients received 0.1 mmol/kg dose Gd-BOPTA intravenously. MRI of both groups was carried out with T1-A FLASH-2D and T2-A TURBO spin echo before contrast injection and T1-A FLASH-2D sequences in dynamic and late phase (90th minute) after the contrast injection. The lesion conspicuity for each image was evaluated qualitatively. Liver signal to noise ratio (SNR), absolute lesion-liver contrast to noise ratio (CNR), mean lesion-liver CNR and contrast enhancement rate of the liver obtained from both groups were compared quantitatively.
While liver contrast enhancement rate in the group receiving standard dose Gd-BOPTA were 41%+/-42 in the arterial phase, 66%+/-58 in the portal phase, 45%+/-45 in the venous phase and 42%+/-88 in the late phase, these values were 43%+/-59, 86%+/-73, 63%+/-75 and 61%+/-105, respectively, in the group receiving the dose of 0.1 mmol/kg. There were no statistically significant differences between the means of both groups. While the absolute lesion-liver CNR values were 18+/-15 precontrast, 22+/-18 in the arterial phase, 19+/-17 in the portal phase, 15+/-10 in the venous phase and 24+/-26 in the late phase in the group receiving the standard dose Gd-BOPTA, these values were 13+/-11, 18+/-15, 15+/-15, 13+/-13 and 19+/-21, respectively, in the group receiving the 0.1 mmol/kg dose. There were no statistically significant differences between the means of both groups (p>0.05). However, when the mean lesion-liver CNR values were compared, there was statistically significant difference between each arterial and portal phases of metastases in both groups (p<0.05). There was no statistical difference found in other lesions. When lesion conspicuity scores were compared, there were no significant differences between the two groups.
In liver lesions, similar diagnostic data are obtained in dynamic and late phase MRI with either standard dose Gd-BOPTA or with a dose of 0.1 mmol/kg. Because there was a difference in only metastases in both groups, in oncological patients who are being investigated for liver metastasis, it is expedient to use a dose of 0.1 mmol/kg.
钆贝葡胺(Gd-BOPTA)是一种肝脏特异性造影剂,在细胞外间隙也有分布,推荐在肝脏病变的磁共振成像(MRI)中按标准剂量(0.05 mmol/kg)使用。然而,在最近的临床实践中,其0.1 mmol/kg剂量的使用逐渐增加。从现在起,在肝脏病变的常规MRI中我们应该使用哪种剂量?本研究调查了标准剂量与0.1 mmol/kg剂量的钆贝葡胺在显示肝脏局灶性病变MRI诊断数据方面的疗效。
该研究纳入了47例肝脏局灶性病变患者。22例患者接受标准剂量,25例患者静脉注射0.1 mmol/kg剂量的钆贝葡胺。两组在注射造影剂前均采用T1-A FLASH-2D和T2-A快速自旋回波序列进行MRI检查,注射造影剂后在动态期和晚期(第90分钟)采用T1-A FLASH-2D序列。对每张图像的病变清晰度进行定性评估。定量比较两组获得的肝脏信噪比(SNR)、绝对病变-肝脏对比噪声比(CNR)、平均病变-肝脏CNR以及肝脏的对比增强率。
接受标准剂量钆贝葡胺组的肝脏对比增强率在动脉期为41%±42,门静脉期为66%±58,静脉期为45%±45,晚期为42%±88;而接受0.1 mmol/kg剂量组的这些值分别为43%±59、86%±73、63%±75和61%±105。两组均值之间无统计学显著差异。接受标准剂量钆贝葡胺组在造影前的绝对病变-肝脏CNR值为18±15,动脉期为22±18,门静脉期为19±17,静脉期为15±10,晚期为24±26;接受0.1 mmol/kg剂量组的这些值分别为13±11、18±15、15±15、13±13和19±21。两组均值之间无统计学显著差异(p>0.05)。然而,比较平均病变-肝脏CNR值时,两组转移瘤的每个动脉期和门静脉期之间存在统计学显著差异(p<0.05)。其他病变未发现统计学差异。比较病变清晰度评分时,两组之间无显著差异。
在肝脏病变中,标准剂量钆贝葡胺或0.1 mmol/kg剂量在动态期和晚期MRI中均可获得相似的诊断数据。由于两组仅在转移瘤方面存在差异,对于正在接受肝脏转移瘤检查的肿瘤患者,使用0.1 mmol/kg剂量是适宜的。