RVT Hemodynamics and Doppler Principles 2

Question 1

Which hemodynamic principle states that flow rate equals the pressure gradient divided by resistance?

Accepted Answer

Ohm's law analogy for blood flow

Answer

Bernoulli's principle

Answer

Poiseuille's law

Answer

Laplace's law

Question 2

In a stenotic vessel, where is the highest flow velocity observed according to the continuity equation?

Accepted Answer

At the site of maximum narrowing

Answer

Proximal to the stenosis

Answer

Distal to the stenosis

Answer

At the vessel wall

Question 3

What does the resistivity index (RI) formula [(PSV - EDV) / PSV] primarily reflect?

Accepted Answer

Downstream vascular resistance

Answer

Cardiac output

Answer

Blood viscosity

Answer

Vessel wall compliance

Question 4

A Doppler angle of 0° between the ultrasound beam and blood flow would result in:

Accepted Answer

Maximum Doppler shift

Answer

Zero Doppler shift

Answer

Aliasing artifact

Answer

Mirror image artifact

Question 5

Which waveform characteristic is most consistent with a high-resistance peripheral arterial system at rest?

Accepted Answer

Triphasic waveform with reverse flow component

Answer

Monophasic forward flow throughout diastole

Answer

Biphasic waveform with brief reverse flow

Answer

Continuous low-velocity forward flow

Question 6

Turbulent flow is most likely to develop when the Reynolds number exceeds approximately:

Accepted Answer

2000

Answer

200

Answer

500

Answer

5000

Question 7

During exercise, peripheral arterial waveforms typically change from triphasic to monophasic because:

Accepted Answer

Peripheral resistance decreases due to vasodilation

Answer

Heart rate decreases

Answer

Blood viscosity increases

Answer

Cardiac output decreases