VT Non-Invasive Testing Procedures 1 — Questions and Answers

Question 1: Which test measures blood pressure differences between limbs to assess arterial disease?

Segmental pressure test
Ankle-Brachial Index (Correct answer)
Venous duplex scan
Reactive hyperemia test

Correct answer: Ankle-Brachial Index

The Ankle-Brachial Index (ABI) is a widely used non-invasive test that measures blood pressure differences between the ankles and arms to assess for peripheral arterial disease (PAD). A ratio of ankle systolic pressure to brachial systolic pressure helps determine the degree of arterial narrowing or blockage in the lower limbs. A low ABI indicates reduced blood flow and potential PAD.

Question 2: Which test is used to evaluate venous reflux and valve function?

Photoplethysmography
Venous duplex ultrasound (Correct answer)
Pulse volume recording
Segmental limb pressure

Correct answer: Venous duplex ultrasound

Venous duplex ultrasound is the primary test used to evaluate venous reflux and valve function, particularly in cases of chronic venous insufficiency. This technique uses both B-mode imaging to visualize the veins and Doppler to assess blood flow direction and velocity. It can detect incompetent valves by observing retrograde blood flow, which indicates reflux.

Question 3: What is the purpose of a pulse volume recording (PVR)?

Measure oxygen levels
Detect heart murmurs
Assess blood volume changes (Correct answer)
Test kidney function

Correct answer: Assess blood volume changes

The purpose of a pulse volume recording (PVR) is to assess blood volume changes in a limb, providing an indirect measure of arterial blood flow. PVR uses pneumatic cuffs to detect pulsatile changes in limb circumference, which correspond to arterial inflow. This non-invasive test helps identify the presence and severity of peripheral arterial disease by evaluating waveform morphology and amplitude.

Question 4: How is photoplethysmography (PPG) used in vascular testing?

Visualize large arteries
Evaluate bone density
Measure venous return using light sensors (Correct answer)
Capture lung function

Correct answer: Measure venous return using light sensors

Photoplethysmography (PPG) is a non-invasive vascular testing method that uses light sensors to measure changes in blood volume in the microvasculature, typically in the skin. It detects variations in light absorption or reflection caused by pulsatile blood flow, which can be used to evaluate venous return, arterial inflow, and capillary refill. PPG is often used for assessing venous reflux or digital perfusion.

Question 5: Which of the following is an advantage of non-invasive vascular testing?

They require sedation
They provide histological diagnosis
They use contrast dyes
They are safe and radiation-free (Correct answer)

Correct answer: They are safe and radiation-free

A significant advantage of non-invasive vascular testing, such as ultrasound or ABI, is that these procedures are generally safe and radiation-free. Unlike imaging modalities like X-rays or CT scans, they do not expose patients to ionizing radiation or require contrast dyes, making them suitable for repeated use and for patients with contraindications to other methods. This enhances patient safety and comfort during diagnostic evaluations.

Question 6: Which measurement is crucial in assessing arterial stenosis with duplex ultrasound?

Vein diameter
Heart rate
Peak systolic velocity (Correct answer)
Blood pH level

Correct answer: Peak systolic velocity

Peak systolic velocity (PSV) is a crucial measurement in assessing arterial stenosis with duplex ultrasound. By measuring the highest velocity of blood flow through a narrowed segment of an artery, technicians can quantify the degree of stenosis. A significant increase in PSV compared to proximal segments is a key indicator of a hemodynamically significant blockage.

VT Non-Invasive Testing Procedures 1

Which test measures blood pressure differences between limbs to assess arterial disease?