FREE ARDMS SPI MCQ Questions and Answers
The following are examples of technologies that use extended sound pulses with a broad frequency range to enhance image quality and penetration:
The pulser's sound pulses are lengthened by coded excitation, which also spreads the peak energy intensity over a wide frequency range. System electronics simultaneously shorten lengthened pulse reflections via a mathematical technique. Axial resolution is aided by this, and image penetration, signal-to-noise ratio, spatial, and contrast resolutions are all improved. A system technology called frequency compounding helps to eliminate sonographic artifacts like noise, speckle, and shadowing. A preprocessing technique called fill-in interpolation boosts the spatial resolution of the displayed image by simulating data between scan lines. Harmonic imaging is a technique where the image is produced using reflected frequencies that are twice as high as the fundamental (transmission) frequency. Harmonic imaging can take many different forms, including pulse inversion, contrast, tissue, and power modulation harmonic imaging.
The phrase that best expresses this is "amplifying image contrast directly at structure boundaries"
Edge enhancement alters contrast and highlighting to emphasize the edge of anatomical structural boundaries. In order to give structures a crisp appearance, this determines their edge. The portrayal of nearby structures that are almost isoechoic may benefit from edge enhancement. System technologies like frequency and spatial compounding help to lessen sonographic artifacts including noise, speckle, and shadowing. A preprocessing technique called fill-in interpolation boosts the spatial resolution of the displayed image by simulating data between scan lines.
Using electrical steering technology, spatial compounding can:
A technique called spatial compounding creates an image from many overlapping frames. Compounding is the term used to describe this frame-overlapping. Each of these frames is acquired from a different angle, and then they are combined to show a single image. In artifacts like shadowing and speckle, the advantages of spatial compounding are reduced; nonetheless, this results in a fall in temporal resolution.
Which color Doppler program precisely takes color out of a flow that flows slowly?
Wall filter uses the color Doppler application to precisely remove color from areas of slow-moving flow. Adjustments to the wall filter are unaffected by high velocities, making it a helpful feature for reducing ghosting phenomenon.
Which display mode shows information about a moving reflector over time?
Heart imaging typically use M-mode. M-mode is frequently used to measure fetal heart rate. In this display mode, the X-axis is used to show variations in the positions of anatomical features over time. On the Y-axis of M-mode, depth is shown.
The easiest way to characterize harmonics produced during reflection and requiring the utilization of microbubbles is:
As microbubbles interact with the acoustic wave, contrast harmonics are formed during the energy conversion from the fundamental to the harmonic frequency. Microbubbles behave nonlinearly, swelling and shrinking when they engage with the acoustic wave. Reflection results in the production of contrast harmonics. Microbubble response and harmonic strength are both determined by the mechanical index (MI). Within soft tissues, harmonics that are related to energy conversion from the fundamental to harmonic frequency are referred to as tissue harmonics. This is due to acoustic energy compressions and rarefactions having a nonlinear behavior when they pass through soft tissue, which reduces the possibility of artifacts appearing inside structures.Another device that sends opposing positive and negative acoustic pulses down each individual scan line is called pulse inversion harmonics. The destructive interference causes these pulses to cancel one another out, leaving just the nonlinear, harmonic reflections. The term "fundamental harmonics" is untrue.
An artifact that results from excessive color gain is known as:
Excess color gain is referred to as color confetti. Instead of just appearing in the area of interest (the vessel), color confetti scatters colors throughout the full color Doppler box. Color bleed and color funfetti are not real words. Crosstalk, which applies to spectral Doppler imaging as opposed to color Doppler imaging, is an artifact that is displayed as the spectral Doppler waveform's mirrored image.