Dual-source parallel RF transmission for diffusion-weighted imaging of the abdomen using different b values: Image quality and apparent diffusion coefficient comparison with conventional single-source transmission

Purpose: To prospectively and intraindividually evaluate what effects dual-source parallel radiofrequency (RF) transmission have on image quality and apparent diffusion coefficient (ADC) of abdomen diffusion-weighted imaging (DWI) using different b values, compared with the single-source RF transmission. Materials and Methods: Eighteen healthy male volunteers were enrolled in this Health Insurance Portability and Accountability Act (HIPAA)-compliant Institutional Review Board (IRB)-approved study. Abdominal DWI was performed with dual-source and single-source RF transmission at 3.0 T using a series of b-value combinations: 0/100, 0/500, 0/800, and 0/100/800. RF field homogeneity, subjective image quality, and signal to noise ratio (SNR) of each abdominal organ were evaluated. ADC values were calculated for each abdominal organ. Wilcoxon test and repeated-measures analysis of variance was used to calculate statistical significance. Results: The parallel RF transmission significantly improved homogeneity of the RF field (P = 0.00010.008) and subjective image quality (P < 0.0001) at each b value and also increased SNR. At lower and higher b value, the measured ADC of lateral left hepatic lobe and spleen between dual-source and single-source images were significantly different (P = 0.00010.047). At b = 0/500, there was no significant difference in ADC measurements between dual-source and single-source RF transmission for abdominal organs, except a slight statistically significant difference for spleen (P = 0.047). Conclusion: Parallel RF transmission significantly improved the image quality and homogeneity of the RF field. The RF transmission had a significant influence on measured ADC of lateral left hepatic lobe and spleen. At b = 0/500 the influence was minimum for all abdominal organs. J. Magn. Reson. Imaging 2013;37:875885. (c) 2012 Wiley Periodicals, Inc.