Table 3

Normalized parameter-ranking results

Parameter nameDefinition
Wall shear stress (WSS)Tangential force per unit area exerted on the aneurysm wall by the bloodflow. This data can be presented as the average, minimum, and maximum across either space or time, and is typically based on WSS vector magnitude.
Low shear stress areaSurface area of aneurysm in which WSS is below a threshold (Ex. 10% of maximum WSS)
Aneurysm sizeMaximum diameter of aneurysm
Size ratioRatio of aneurysm size to parent vessel diameter
Aspect ratioRatio of maximum aneurysm height to aneurysm neck width
Oscillatory shear indexDimensionless measure of how much the instantaneous WSS vector is aligned with the time- averaged WSS vector (measure of changes in direction of shear forces on wall during cardiac cycle). Please refer to 32 for mathematical formula).