[Influence of Different Contrast Agent Concentrations and Injection Protocols on Dynamic Contrast Enhanced MRI of Prostate: Equimolar Comparison of 1.0M Gadobutrol and 0.5M Gadolinium Chelates].

The purpose of this study was to evaluate the enhancement profile of 1.0M gadobutrol (high concentration: HC) in comparison to 0.5M gadopentetate dimeglumine and gadoterate meglumine (low concentration: LC) in dynamic contrast enhanced magnetic resonance imaging (DCE-MRI) of prostate. In total, 48 patients who were diagnosed with prostate cancer by radiologist were included. Each patient was examined after intravenous injection of 0.1 mmol/kg body weight contrast agent with flow rate of 1.5 (HC) or 3.0 mL/s (LC). Circular regions of interest were placed at prostate cancer (PCa) and normal peripheral zone (normal PZ) in DCE-MRI. The enhancement curves were calculated as a relative enhancement. Statistical analysis was performed by Mann-Whitney U test (p<0.05 were considered significant). As a result, the enhancement at first phase of HC was significantly lower compared with LC in PCa (HC, 0.47; LC, 0.85; p=0.029), and in normal PZ (HC, 0.12; LC, 0.22; p=0.033). The enhancement of HC in PCa was significantly higher compared with LC at late phase. Although not significant, a similar tendency was observed in normal PZ. The present study suggested that the enhancement profile with HC was higher at late phase but the rise of the enhancement curve with HC tended to be delayed.