两种不同弛豫率钆对比剂在脑转移瘤中的磁共振对比研究

Comparison of two gadolinium-based contrasts with different T1 relaxation rates in MR imaging of brain metastases

目的对比研究钆贝葡胺(Gd-BOPTA)与钆喷酸葡胺(Gd-DTPA)在磁共振增强检查中对脑转移瘤的诊断价值。方法第一部分:回顾性分析40例无颅内疾患成人MR增强图像资料,其中20例应用钆贝葡胺,另20例应用钆喷酸葡胺,均使用标准剂量(0.1mmol/kg体重),两组年龄、体重相匹配,比较两组下鼻甲与正常脑白质的对比噪声比。第二部分:10例临床诊断为脑转移瘤患者间隔24～48小时分别用标准剂量(0.1mmol/kg体重)钆贝葡胺与钆喷酸葡胺行磁共振增强检查,比较二者对转移瘤的显示情况及病灶与对侧正常脑白质的对比噪声比。结果第一部分:钆贝葡胺组下鼻甲与正常脑白质的对比噪声比(36.6±11.9)高于钆喷酸葡胺组(25.6±8.1),P=0.002。第二部分:10例脑转移瘤中有3例钆贝葡胺增强检查比钆喷酸葡胺增强检查多检出一小病灶;5例钆贝葡胺比钆喷酸葡胺对病灶强化更明显;另2例两者无明显差别。钆贝葡胺与钆喷酸葡胺增强后病灶与对侧正常脑白质的平均对比噪声比前者(22.5±10.5)明显高于后者(12.0±6.4),P<0.009。结论同等剂量条件下,使用钆贝葡胺行MR增强检查不仅使脑转移瘤显示更清晰,对比更明显,而且能提高隐匿性病灶的检出率,改善临床治疗方案。

Objective To compare the enhancement characteristics of Gadobenate dimeglumine（Gd-BOPTA）and Gadopentetate dimeglumine（Gd-DTPA）with a standard dose in brain metastases.Methods The first part,MRI data of 40 adults with no intracranial lesions were retrospectively analyzed,in 20 cases of which Gadobenate dimeglumine was used as the contrast media,in another 20 cases Gadopentetate dimeglumine was the contrast media（0.1 mmol/kg）.The ages and weights in two groups were matched.The contrast-to-noise ratios of inferior nosal concha to normal brain white matter were compared.The second part,10 consecutive patients diagnosed as brain metastasis underwent MR imaging twice with Gadobenate dimeglumine and Gadopentetate dimeglumine（0.1 mmol/kg）as the contrast media respectively.The interval between two examinations was 24—48 hours.The detection and delineation of lesions were evaluated visually.The contrast-to-noise ratios of lesion to normal brain white matter were calculated and compared between the two examinations.Results The first part,The mean contrast-to-noise ratio of inferior nosal concha to normal brain white matter in Gadobenate dimeglumine group（36.6±11.9）was higher than Gadopentetate dimeglumine group（25.6±8.1）,P=0.002.The second part,after administration of Gadobenate dimeglumine one additional small lesions were detected compared with Gadopentetate dimeglumine in 3 of the 10 patients.In 5 cases the lesion enhancement were more intense with Gadobenate dimeglumine than Gadopentetate dimeglumine.In another 2 cases the lesion enhancement were similar between the two by visual assessment.The contrast-to-noise ratios of lesion to normal brain white matter were higher with Gadobenate dimeglumine（22.5±10.5）than that with Gadopentetate dimeglumine（12.0±6.4）,P〈0.009.Conclusion With standard dose of 0.1 mmol/kg,the lesion enhancement and delineation were superior with Gadobenate dimeglumine than that with Gadopentetate dimeglumine,and occult lesions can be detected with Gadobenate dimeglumine,so therapy strategy can be improved accordingly.