Pressure is reduced _____ to a stenosis in turbulent flow.

Pressure is reduced _____ to a stenosis in turbulent flow.

• A. Distal
• B. Proximal
• C. Across
• D. Through

Answer: (B)

In turbulent flow through a stenosis, energy losses from friction, eddies, and flow separation create a pressure gradient as the fluid accelerates into the narrowed passage. The static pressure drops as the flow moves toward the constriction, so the region just upstream of the stenosis (the proximal side) experiences a reduced pressure compared with the normal upstream area. After the flow passes the narrowest point, it often recovers pressure downstream, though some loss remains. So the statement is capturing where the pressure reduction is most clearly observed relative to the stenosis in turbulent conditions—the proximal side upstream of the constriction.

In turbulent flow through a stenosis, energy losses from friction, eddies, and flow separation create a pressure gradient as the fluid accelerates into the narrowed passage. The static pressure drops as the flow moves toward the constriction, so the region just upstream of the stenosis (the proximal side) experiences a reduced pressure compared with the normal upstream area. After the flow passes the narrowest point, it often recovers pressure downstream, though some loss remains. So the statement is capturing where the pressure reduction is most clearly observed relative to the stenosis in turbulent conditions—the proximal side upstream of the constriction.