ARRT Vascular-Interventional Radiography flashcards
ARRT Vascular-Interventional Radiography · Build recall with a focused review session.
31 cards. Read the term and the definition here. The deck at the top of this page is optional.
- Mask image
- A pre-contrast fluoroscopic frame stored by the digital subtraction system and subtracted from subsequent contrast-filled frames to isolate opacified vessels.
- Misregistration artifact
- Artifact in digital subtraction angiography caused by patient motion between mask and contrast frame acquisition, producing dark or light halos at vessel margins.
- Remasking
- Post-processing technique in which a different frame is chosen as the mask, or the mask is pixel-shifted, to correct patient-motion misregistration without re-exposing the patient.
- Roadmapping
- Technique that overlays a stored contrast-enhanced vessel image on live fluoroscopy, allowing catheters and guide wires to be navigated without repeated contrast injections.
- Quantum mottle
- Grainy image noise that results when too few x-ray photons reach the detector; it is reduced by increasing exposure rather than by window and level adjustment.
- Bit depth
- The number of binary digits assigned to each pixel, determining the number of gray levels displayed; a 10-bit image shows 1024 levels.
- Magnification mode
- A fluoroscopic setting that images a smaller detector area to increase spatial resolution, but requires higher exposure and therefore increases patient dose.
- Informed consent
- Documented patient agreement obtained after explaining the procedure, its benefits, material risks such as bleeding and contrast reaction, and available alternatives.
- Contrast-induced nephropathy
- Acute decline in renal function following iodinated contrast administration, with risk increased by pre-existing renal insufficiency, diabetes, dehydration, and large contrast volume.
- Contrast premedication
- A corticosteroid with an antihistamine given before iodinated contrast to patients with a prior anaphylactoid reaction, typically beginning 13 hours before the study.
- Metformin hold
- Practice of withholding metformin after iodinated contrast in patients with renal impairment because of lactic acidosis risk, with reinstitution after renal function reassessment.
- Pseudoaneurysm
- A contained collection of blood communicating with an artery through a defect in the vessel wall, often signaled by a new pulsatile mass at the access site.
- Distal pulse check
- Assessment of pulses, capillary refill, color, temperature, and sensation in the accessed extremity, documented before and after angiography to detect vascular compromise.
- eGFR screening
- Estimated glomerular filtration rate calculated from serum creatinine, used to identify patients at elevated risk for contrast-induced nephropathy before angiography.
- Seldinger technique
- Vascular access method using needle puncture, guide wire insertion, needle removal, and catheter advancement over the wire, with the wire secured throughout.
- Cobra catheter
- A selectively shaped diagnostic catheter with a curved tip used to engage visceral and abdominal branch vessels arising at moderate angles from the aorta.
- Balloon sizing
- Selection of an angioplasty balloon whose diameter matches the adjacent normal vessel; oversizing risks dissection or rupture and undersizing leaves residual stenosis.
- Stent landing zone
- The segment of relatively normal vessel proximal and distal to a lesion that must be adequate to anchor a stent and prevent migration.
- Embolization coils
- Metallic coils delivered into a vessel to induce thrombotic occlusion; they provide permanent, precise, relatively proximal occlusion of the target vessel.
- Gelatin sponge
- A temporary embolic agent that occludes intermediate-sized vessels and is resorbed over weeks, useful when temporary occlusion is desired.
- IVC filter
- A device placed in the inferior vena cava to trap thromboemboli, indicated when anticoagulation is contraindicated or has failed in a patient with deep vein thrombosis.
- TIPS procedure
- Creation of a transjugular channel between the hepatic vein and portal vein to decompress portal hypertension, used for variceal bleeding or refractory ascites.
- Inverse square law
- The principle that radiation dose rate decreases with the square of the distance from the source, so doubling distance reduces dose to one quarter.
- Last-image-hold
- A fluoroscopic function that freezes the most recent frame on the monitor, allowing review without additional radiation exposure to the patient.
- Pulsed fluoroscopy
- Fluoroscopic operation in which x-rays are produced in discrete pulses; lower pulse rates proportionally reduce patient dose compared with continuous fluoroscopy.
- Collimation
- Restriction of the x-ray beam to the region of interest, which reduces patient dose and improves contrast by limiting scattered radiation reaching the detector.
- Dose-sparing geometry
- Positioning the detector close to the patient and the tube far from the patient, which reduces entrance skin dose while maintaining image quality.
- Air kerma
- A measure of radiation energy absorbed per unit mass of air at a point, displayed on interventional systems as a patient dose indicator in milligray.
- Kerma-area product
- The product of air kerma and beam cross-sectional area, expressed in Gy·cm², used to estimate total radiation dose delivered during a procedure.
- Dosimeter placement
- Personnel radiation monitor worn at collar level outside the lead apron to estimate dose to the unshielded head and neck region.
- kVp and dose
- Fluoroscopic dose rate is approximately proportional to the square of tube potential, so lowering kVp reduces dose but also reduces beam penetration.