Free ARDMS SPI MCQ Questions and Answers — Questions and Answers
Question 1: Which display mode shows information about a moving reflector over time?
- M-mode (Correct answer)
- Z-mode
- A-mode
- B-mode
Correct answer: M-mode
M-mode, or Motion mode, displays a single scan line over time. The horizontal axis represents time, and the vertical axis represents depth, showing the movement of structures along that specific line. This display mode is ideal for visualizing and quantifying motion, such as cardiac wall movement or fetal heart rate, by tracking changes in reflector position over time.
Question 2: The phrase that best expresses this is "amplifying image contrast directly at structure boundaries"
- Fill-in interpolation
- Edge enhancement (Correct answer)
- Spatial compounding
- Frequency compounding
Correct answer: Edge enhancement
Edge enhancement is a post-processing technique designed to improve the visual clarity of anatomical structures. It works by selectively amplifying the contrast at the boundaries between different tissues or structures, making the edges appear sharper and more defined. This process enhances the perception of detail without altering the raw data.
Question 3: Using electrical steering technology, spatial compounding can:
- Improve temporal resolution
- Increase frame rate
- Decrease speckle artifact (Correct answer)
- Enhance shadowing artifact
Correct answer: Decrease speckle artifact
Spatial compounding acquires multiple scan lines from different angles using electrical steering and then averages them to create a single composite image. By viewing structures from various perspectives, random noise and speckle artifacts, which are angle-dependent, are significantly reduced. This leads to a smoother image with improved contrast resolution and better visualization of tissue textures.
Question 4: The following are examples of technologies that use extended sound pulses with a broad frequency range to enhance image quality and penetration:
- Frequency compounding
- Interpolation
- Harmonic imaging
- Coded excitation (Correct answer)
Correct answer: Coded excitation
Coded excitation is an advanced technology that uses a complex, encoded sequence of sound pulses instead of a single short pulse. This technique broadens the frequency spectrum of the transmitted signal and significantly improves the signal-to-noise ratio. The result is enhanced image quality, better penetration, and improved axial resolution, particularly beneficial for imaging deeper structures.
Question 5: The easiest way to characterize harmonics produced during reflection and requiring the utilization of microbubbles is:
- Tissue harmonics
- Fundamental harmonics
- Contrast harmonics (Correct answer)
- Pulse inversion harmonics
Correct answer: Contrast harmonics
Contrast harmonics are specifically generated when ultrasound microbubble contrast agents oscillate non-linearly in response to the incident sound wave. These microbubbles, when reflecting sound, produce harmonic frequencies that are distinct from those generated by tissue. This phenomenon is utilized to enhance the visualization of blood flow and perfusion in contrast-enhanced ultrasound imaging.
Question 6: Which color Doppler program precisely takes color out of a flow that flows slowly?
- Decreasing PRF
- Wall filter (Correct answer)
- Increasing PRF
- Color gain
Correct answer: Wall filter
The wall filter (or high-pass filter) in Doppler ultrasound is specifically designed to eliminate low-frequency, high-amplitude signals produced by stationary or slowly moving structures, such as vessel walls or tissue motion. By filtering out these clutter signals, it allows for better visualization of true blood flow, especially slow flow, preventing artifactual color display from tissue movement.
Question 7: An artifact that results from excessive color gain is known as:
- Color confetti (Correct answer)
- Color bleed
- Color funfetti
- Crosstalk
Correct answer: Color confetti
Color confetti is an artifact that occurs when the color gain in Doppler ultrasound is set excessively high. It manifests as random, spurious color pixels appearing throughout the image, often outside of vessels or in areas of no flow. This happens because the system amplifies even very weak noise signals to the point where they are incorrectly interpreted and displayed as blood flow.
Free ARDMS SPI MCQ Questions and Answers
Which display mode shows information about a moving reflector over time?