OPTIMAL DOSE OF MR CONTRAST AGENT IN T1-WEIGHTED MRI

Nowadays magnetic resonance imaging (MRI) has been commonly used in many indications. Concurrent development of MRI contrast agents has aided the rapid expansion and increased clinical efficacy. The use of contrast agents can improve lesion detection and characterization. With the contrast enhancement, lesion conspicuity is dramatically increased. Therefore, contrast enhanced MRI could provide more accurate diagnosis and be helpful for further therapy. The routinely used dose of contrast agents suggested by the documents only relies on the body weight of the subject. However, the relationship between the signal enhancement and the dose of contrast agents needs to be further investigated in order to achieve the maximum enhancement from optimal dose of the contrast agents. The aim of this study is to obtain the optimal dose of two contrast agents (Magnivist and Omniscan) for various T1-weighted pulse sequences (SE, SPGR, 2D TOF and 3D TOF) and various coils (body coil, NV array coil and head coil). The optimal dose is defined as achieving the MR images with the highest enhancement. The results show that there are significant differences in optimal dose among various pulse sequences. However, there are no significant differences in optimal dose among various coils and these two contrast agents. The advantage of finding optimal dose is to minimize dose and potential toxicity, and furthermore to decrease the cost of contrast agents. This study was done on a phantom, and it is expected to provide useful information to the contrast enhanced MRI in the routine clinical diagnosis and research in the future.