The CEST signal is defined as the reduction in bulk water signal intensity that results from chemical exchange of water protons when a saturation pulse
is applied at given frequencies; 3.5, 3.0, 2.0, and 1.0 ppm, respectively, with water set to 0 ppm.
In order to distinguish between high and low CBF, a saturation pulse
can be applied over the labelling plan after blood water labelling (TI1) to cutoff the tagging tail (Figure 14).
With regard to scanning technique, early imaging parameters of peripheral nerves typically utilized fat suppression based on chemical selective saturation pulses
or the STIR method  and fast T2 weighting techniques such as fast spin echo .
6) and optimize the center frequency and fat saturation pulses
with a manual prescan to confirm that correct values have been set for these components.
* The use of MTC saturation pulses
limits the time available for an acquisition.