Diagnostic Imaging Techniques Flashcards

Which modality is most commonly used to evaluate blood flow in arteries and veins?

Answer: Doppler ultrasound

Doppler ultrasound is the most commonly used non-invasive modality for evaluating blood flow in both arteries and veins. It uses sound waves to detect and measure the speed and direction of blood flow, providing crucial information about vessel patency and the presence of blockages. Its real-time imaging capabilities make it invaluable for diagnosing vascular conditions.

What does color Doppler imaging provide?

Answer: Blood flow visualization

Color Doppler imaging enhances traditional ultrasound by providing a visual representation of blood flow within vessels. It assigns different colors to indicate the direction and velocity of blood flow, allowing technicians to quickly identify areas of normal flow, turbulence, or absence of flow. This visualization is essential for assessing vascular health and detecting abnormalities.

Which technique is best for detecting deep vein thrombosis (DVT)?

Answer: Compression ultrasound

Compression ultrasound is considered the gold standard for detecting deep vein thrombosis (DVT). This technique involves applying pressure with the ultrasound transducer to compress the vein; a healthy vein will compress completely, while a thrombosed vein will not. The inability to compress the vein is a direct indicator of a clot, making it a highly effective diagnostic tool.

What role does spectral Doppler play in vascular testing?

Answer: Displays flow velocity waveforms

Spectral Doppler plays a crucial role in vascular testing by displaying blood flow velocity waveforms. These waveforms provide quantitative data on the speed and characteristics of blood flow, allowing for detailed analysis of arterial and venous hemodynamics. This information is vital for assessing the severity of stenosis, identifying turbulent flow, and evaluating vascular resistance.

Which imaging technique requires contrast injection to visualize vessels?

Answer: CT angiography

CT angiography (CTA) is an imaging technique that specifically requires the injection of an iodinated contrast dye into the bloodstream to visualize blood vessels. The contrast agent highlights the arteries and veins on CT scans, allowing for detailed anatomical assessment and detection of blockages, aneurysms, or other vascular abnormalities. Without contrast, the vessels would not be clearly distinguishable from surrounding tissues.

What does a triphasic waveform indicate in arterial testing?

Answer: Normal arterial flow

A triphasic waveform in arterial testing indicates normal arterial flow, characterized by three distinct phases: a rapid antegrade flow during systole, a brief reversal of flow during early diastole, and a small antegrade flow component in late diastole. This pattern signifies healthy, high-resistance arterial flow without significant blockages. Its presence suggests good vascular health in the tested artery.