Comparison of T1-weighted spin-echo and gradient-echo sequences in hepatic magnetic resonance studies with mangafodipir (Teslascan)

Mangafodipir (MnDPDP, Teslascan) is a positive contrast medium that enhances the contrast between the liver and focal lesions. It is especially useful in the detection of small, poorly discernible hepatic lesions. Our objective is to determine which T1-weighted sequence is more sensitive to contrast uptake and which is more reliable in the detection of lesions. A clinical trial was carried out in a series of 112 patients who presented between 1 and 5 local hepatic lesions. All underwent magnetic resonance imaging (1.0 T and 0.5) using T1-weighted spin-echo (SE) and gradient-echo (GE) sequences before and after the intravenous administration of MnDPDP (10 mmol/ml). The number of lesions detected was recorded and, in 80 patients, the signal-to-noise ratio (SNR) and the relative uptake factor (RUF) were calculated. Student <> test was used to compare the means for SNR and RUF and Wilcoxon's test for paired data was employed to analyze the number of lesions. T1-weighted GE sequences were more sensitive to the presence of MnDPDP in the liver parenchyma and more effective in the detection of hepatic lesions that SE. We recommend the use of T1-weighted Ge sequences over SE for the study of the liver after MnDPDP administration. (Author) 7 refs