Volumetric vs. Linear Reduction of Arterial Stenosis for Trans-stenotic Pressure Gradient in Image-based Computational Hemodynamics

Arteries, transport oxygenated blood, is essential for sustaining life functions. Lumen reduction of an artery, known as arterial stenosis, causes insufficient blood supply and may lead to a fatal consequence such as heart attack and ischemic stroke. While the linear (diameter) reduction of arterial lumen has been a practical measurement, trans-stenotic pressure gradient is a more accurate measurement for determining the severity of blood flow blockage therefore image-based computational hemodynamics has emerged as a unique and powerful tool to noninvasively quantify the trans-stenotic pressure gradient in human arteries. In this work, we use a developed and validated in-house computation package, named InVascular, to study the relationship between the lumen reduction and trans-stenotic pressure gradient, aiming to provide more appropriate measurement of the severity of a diagnosed arterial stenosis from CT or MRI imaging. Through the parametrization of an image-based renal stenosis, fixing volumetric reduction with varying linear reduction and fixing linear reduction with varying volumetric reduction, by deteriorating the 3-D shape of the stenosis, we demonstrate that volumetric reduction of the renal lumen is more accurate to reflect the trans-stenotic pressure gradient.