Indeed, there’re many parameters to keep in mind: frequency in B-mode, Colour, Pulsed, gain, scale, beam steering, Dopple sample gate, angle, heel and toe, etc. It is quite overwhelming!
For grading stenosis, does your PSV has to agree with the ICA/CCA ratio when trying to categorise the extent of a stenosis? For example for a 70% stenosis, if I get >270 cm/s for PSV, do I need to get a ICA/CCA of >4 to make it consistent or vice versa?