With b = 0 bright signals are noted in multiple veins due to the high T2 of blood coupled with sluggish flow. This array of multiple white dots on the b0 image makes distinguishing cysts, masses, and vessels difficult. By raising the starting b-value to a low number like 50-100, these vascular white dots disappear, providing a cleaner visualization of the hepatic parenchyma.
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Other than liver imaging, I know of no reason why body imagers would choose b=50 instead of b=0 starting values elsewhere in the abdomen and pelvis. Perhaps it is simply habit that b=50 values are used in these other areas.
Unless multi-component ADC values need to be calculated, this small difference in starting b-values (0 vs 50) makes no significant difference in the single-component ADC maps commonly used.
Qayyum A. Diffusion-weighted imaging in the abdomen and pelvis: concepts and applications. Radiographics 2009; 29:1797-1810.
What is meant by the b-value? How do I pick it?