顺磁性造影剂Gd-DTPA与FAC弛豫增强特性的实验研究  

Relaxational Characters of Paramagnetic Contrast AgentsGdDTPA and FACin Experimental Study

作　　者：戴平丰[1,2] 刘继汉[1,2] 余伟南[1,2] 

机构地区：[1]浙江医科大学邵逸夫医院影像科 [2]西安医科大学一附院影像中心

出　　处：《中国医学计算机成像杂志》1998年第1期60-63,共4页Chinese Computed Medical Imaging

摘　　要：目的：明确顺磁性造影剂ＧｄＤＴＰＡ与ＦＡＣ（枸橼酸铁铵）的驰豫增强规律，比较两者的增强效率。材料和方法：将两种造影剂分别配制成１２种不同的浓度，装入试管后多次重复成像，测量驰豫时间和信号强度进行分析研究。结果：ＧｄＤＴＰＡ与ＦＡＣ的驰豫增强规律十分相似。驰豫时间随造影剂浓度的增加而缩短，但Ｔ１、Ｔ２的变化速度和规律不同。信号强度的变化具有双向性，低浓度时呈阳性造影效果，且信号强度随浓度增高而升高；达到一度浓度后信号强度反而随浓度增加而下降，高浓度时则出现阴性造影效果。信号变化的转折点在不同参数成像时不同步。当ＦＡＣ的浓度为ＧｄＤＴＰＡ的四倍时两者达到同样的增强幅度。作者对浓度、驰豫时间和信号强度三者的关系作了深入的分析。结论：ＧｄＤＴＰＡ与ＦＡＣ均为顺磁性造影剂，明确其增强特性与增强效率可为与顺磁质有关的信号演变的解释及胃物道造影剂的选择提供理论根据。urpose: To clarify the relaxivity and to compare the efficiency of paramagnetic contrast agents GdDTPA and FAC(ferric ammoniam citrite). Materials and Mathods: Twelve different concentrations were prepared for both contrast agents.SE T1W,T2W images were repeatedly done in defferent time with same scan parameters.Relaxation times and signal intensities were measured and analysed. Results:GdDTPA and FAC have simillar relaxation property.Relxation time shortens with increase of concentration.But the shortening effects on T1 and T2 were very different. The change of signal intensity showed a biphasic characteristics. At low concentration,positive enhancement was presented and the signal intensity increase with higher concentration. At high concentration, a negtive contrast enhancement was shown,the turning point of the signal change was not synchronous in various kinds of defferent weighed images.When the concentration of FAC was four times as high as that of GdDTPA,they would have same degree of enhancement. The author deeply explored the relations among the relation time,signal intensity,and the concentration.Conclusion:GdDTPA and FAC are paramegnetic contrast agents,the clarifying of their relaxation enhancing character can give a new way for the explanation of signal change of hematoma which has a close relation to paramegnetic matearial Fe. and can also help to select oral contrast agent.

关 键 词：造影剂 实验研究 枸橼酸铁铵 弛豫增强特性 

分 类 号：R981.1[医药卫生—药品]