Sonographic Formulas
John C. Sciarra
Ok, there is really no other way to put it. Memorize these!!!!!!!!!!!!!!!!!!! Some you probably already know, others are Greek. So just write them out over and over until you have them memorized.
Gradient = 4 × Velocity squared
Area of a cylinder thing = 0.785 × D squared
Area of a triangle = 0.433 × Side squared
Deceleration time mv area = 759/DT (ms)
Pisa area = 2 pi R squared × alpha angle/180 (angle stuff is one if no angle)
Pisa flow = 2 pi R squared × Aliasing Velocity
Pisa MV area = 2 pi R squared × alpha/180 × Aliasing Velocity/Peak Velocity
Continuity equation: what goes in comes out. (Note: you can sub peak vel for TVI.)
Here I will go over some that are not quite obvious. The hemodynamic section will explain most of these again.
