Banishing Ghosts in MRI: A Clever Trick with Dual-polarity Readout

You know how ghosts can show up in your MRI scans, making it hard to see what's really going on? This happens due to something called Nyquist ghosting. A clever trick called dual-polarity readout can fix this, but it usually takes twice as long. Researchers have found a way to make this trick work faster and better! In simple terms, they discovered that these ghosts are more noticeable at low b-values. But if you set the b-value to 1000 s/mm², the ghosts almost disappear. They tested this on healthy volunteers and saw that ghosting was hardly noticeable at this higher b-value.The scientists also showed how important this trick is by scanning people using a special technique called tensor-valued diffusion encoding. This helps estimate things like mean diffusivity and mean kurtosis. Without the dual-polarity readout, ghosts messed up these estimates. But with it, the scans were clear and accurate. So, the takeaway is that using dual-polarity readout at these higher b-values can eliminate ghosts and doesn't need extra scan time. This is great news for any MRI scan that averages signals at low b-values.