Fluoroscopy and Interventional Radiography Flashcards
7 cards from real CAMRT practice questions. Tap to flip, then mark Knew It or Still Learning — missed cards come back until you master them.
Read the first 7 Fluoroscopy and Interventional Radiography flashcards as text
What is the primary characteristic that distinguishes fluoroscopy from conventional radiography?
Answer: It provides real-time, continuous X-ray imaging
Fluoroscopy provides real-time, continuous X-ray imaging, allowing visualization of dynamic physiological processes such as swallowing or vessel flow.
In a conventional image intensifier, what is the correct sequence of conversions that produces a visible fluoroscopic image?
Answer: X-rays → input phosphor (light) → photocathode (electrons) → output phosphor (light) → TV camera
The image intensifier converts X-rays to light via the input phosphor, then to electrons via the photocathode; electrons are accelerated to the output phosphor, producing a bright, minified image captured by the TV camera.
What is the typical entrance skin dose rate range during standard fluoroscopy?
Answer: 1–10 mGy/min
Standard fluoroscopy delivers entrance skin dose rates of approximately 1–10 mGy/min, though high-dose-rate fluoroscopy modes can exceed this range.
What is the function of the 'last image hold' (LIH) feature in fluoroscopic equipment?
Answer: It displays the most recently acquired fluoroscopic frame as a static image without ongoing radiation
LIH captures and displays the last acquired fluoroscopic frame as a static image, allowing the operator to review the image without continuing to expose the patient to radiation.
What is the primary purpose of the automatic brightness control (ABC) system in a fluoroscopic unit?
Answer: To automatically adjust kVp and/or mA to maintain consistent image brightness as attenuation changes
ABC automatically adjusts exposure parameters (kVp and/or mA) to compensate for changes in tissue thickness or density, maintaining consistent image brightness throughout the examination.
During a barium swallow examination, why are multiple projections (AP, lateral, oblique) obtained rather than a single view?
Answer: To comprehensively evaluate esophageal anatomy and function from all angles and detect lesions that may be obscured in one view
Multiple projections are required to fully assess esophageal morphology and motility, as lesions or structural abnormalities may be hidden behind overlying structures in any single projection.
At what cumulative fluoroscopic time does most current guidance recommend that the operator be alerted to monitor for potential high skin dose?
Answer: 5 minutes
Many regulatory and professional guidelines recommend alerting thresholds at 5 minutes of cumulative fluoroscopy time as a reference level to prompt dose monitoring and documentation in lengthy procedures.