How do you calculate % stenosis in a vessel?

To determine the percentage stenosis in a vessel, the formula used focuses on the relationship between the diameter of the vessel at its minimal point (the narrowed area, denoted as d) and the diameter of the normal, unaffected segment of the vessel (denoted as D). The formula ( [1 - (d/D)] \times 100 ) effectively captures this relationship.

When calculating percent stenosis, the diameter of the vessel is compared before and after the stenosis. The key concept here is that percentage stenosis reflects how much the vessel diameter has been reduced compared to the normal diameter. By using the expression ( (d/D) ), you are determining how much of the normal diameter remains at the site of stenosis. Subtracting this ratio from 1 gives you the proportion of the diameter that has been lost due to stenosis, which can then be converted into a percentage by multiplying by 100.

This formula is crucial for quantifying stenosis and is frequently applied in vascular imaging and assessment. Being able to accurately calculate % stenosis is vital for determining the severity of vascular disease and potential treatment strategies.