CAMRT Fluoroscopy and Interventional Radiography 3

Question 1

In percutaneous transluminal angioplasty (PTA), what is the mechanism by which the balloon catheter restores blood flow?

Accepted Answer

It is inflated within a stenotic vessel segment to mechanically dilate the narrowing and restore luminal diameter

Answer

PTA uses high-pressure balloon inflation to compress atherosclerotic plaque against the vessel wall and plastically deform the artery, increasing luminal diameter without surgical incision.

Question 2

In digital subtraction angiography (DSA), what is a 'mask' image and how is it used?

Accepted Answer

A pre-contrast baseline image electronically subtracted from contrast-filled frames, leaving only opacified vessels visible

Answer

The mask is a pre-contrast image acquired immediately before contrast injection; it is logarithmically subtracted from each subsequent contrast frame so that bones and soft tissues cancel out, leaving only the contrast-filled vascular structures.

Question 3

What are the key steps of the Seldinger technique for vascular access in interventional radiology?

Accepted Answer

Needle puncture of vessel, guidewire insertion through needle, needle removal, catheter advancement over guidewire

Answer

The Seldinger technique uses a guidewire as an intermediary: the vessel is punctured with a needle, a flexible guidewire is inserted through the needle lumen, the needle is withdrawn, and a catheter is then threaded over the guidewire into the vessel.

Question 4

Which combination of radiation protection measures is most important for the interventional radiologist who must stand near the patient during fluoroscopic-guided procedures?

Accepted Answer

Wearing a full lead apron, thyroid collar, and leaded glasses, and maximizing distance from the beam when possible

Answer

Because interventionalists work in close proximity to the scatter source, comprehensive personal shielding (lead apron ≥0.5 mm Pb, thyroid collar, leaded glasses) combined with distance maximization are the primary occupational dose control measures.

Question 5

In percutaneous nephrostomy, which anatomical approach and calyceal target are preferred to minimize vascular injury?

Accepted Answer

Posterior flank approach targeting a posterior calyx, typically in the lower pole

Answer

The posterior flank approach targets a posterior calyx (usually lower pole) because posterior calyces lie in the avascular plane of Brödel between the anterior and posterior segmental arteries, minimizing risk of hemorrhage.

CAMRT - Canadian Association of Medical Radiation Technologists Practice Test

CAMRT - Canadian Association of Medical Radiation Technologists Practice Test

CAMRT Fluoroscopy and Interventional Radiography 3