CCI: Physics of Ultrasound-URR Questions With Answers Graded A+ Assured Success

Frequencies used in transthoracic imaging are usually in the range of ____________. Frequencies used in transesophageal imaging are usually in the range of ______________. A) 3-6 MHz;6-8 MHz B) 3-6 MHz; 5-7 MHz C) 2.5-4 MHz; 5-7 MHz D) 1-3 MHz; 6-8 MHz - 2.5-4 MHz; 5-7 MHz Which of the following will aid in visualization of the endocardium? A) Increased transducer frequency B) Larger sector size C) Increased wall filter D) Agitated saline contrast - Increased transducer frequency-this will improve spatial and contrast resolution Which of the following adjustments will change the image data that will be stored in the memory of the ultrasound system? A) Both pre-processing and post-processing B) Post-processing C) Changing monitor contrast settings at the beginning of the exam. D) Pre-Processing - Pre-processing-is performed as the image is "live" or in real time, before it has been stored to memory. Which measurement of beam intensity is used to describe levels of intensity associated with US bioeffects? A) Spatial peak temporal peak B) Spatial average temporal peak C) Spatial average temporal averageD) Spatial peak temporal average - Spatial peak temporal average Which of the following technical factors can negatively affect the 2D planimetry evaluation of the mitral valve? A) Valve masking from mechanical MVR and lateral resolution B) Transducer with a short spatial pulse length and long wavelength C) Lateral resolution and gain settings D) Transducer with a short spatial pulse length and high frequency - Lateral resolution and gain settings ________________ occurs posterior to highly attenuating structures. A) Misregistration B) Refraction C) Shadowing D) Enhancement - Shadowing If you increase the power output on the machine: A) Beam intensity and beam penetration increases B) Beam intensity and the magnitude of the doppler shift increases C) Beam intensity, resolution and beam penetration increase D) Beam penetration and the magnitude of the doppler shift increase - Beam intensity and beam penetration increase All of the following are techniques used to better visualize the LV apex in the apical view, except? A) Change to a lower frequency transducer B) Contrast administration C) Apply color doppler to the LV chamber D) Adjust focal zone depth - Change to a lower frequency transducer-a lower frequency probe will improve penetration but decrease resolutionWhich of the following ultrasound techniques has the highest temporal resolution? A) 3D imaging B) 2D imaging C) Color doppler D) M-Mode - M-Mode Lateral resolution is defined as: A) The ability to differentiate two reflectors that are perpendicular to the US beam B) The ability to differentiate two reflectors that are moving in a direction parallel to the US beam C) The ability to differentiate two reflectors that are parallel to the US beam D) The ability to differentiate two reflectors that are moving in a direction that is perpendicular to the US beam - The ability to differentiate two reflectors that are parallel to the US beam When does aliasing occur? - When the frequency shift exceeds the PRF of the transducer Which of the following system control adjustments will increase the amount of color doppler that is superimposed over the 2D image? A) Increased threshold and increased persistence B) Decrease persistence C) Increased wall filter D) Decreased threshold - Increased threshold and increased persistence-Threshold control=Color priority While scanning the heart from the apical window, the ventricular chambers are anechoic but artifactual echoes appear to fill the atria. Which of the following adjustments of the system controls would best address this issue? A) Decrease near field gain levels B) Switch to a higher frequency transducer C) Increase output power to increase penetrationD) Decrease far field gain - Decrease far field gain-adjusting the power output can improve the image but it should always be performed after all other image improvement techniques have been used Which of the following is related to an increase in the spatial pulse length of an US beam produced by the transducer? A) Decreased imaging depth B) Increased beam width C) Remove a focal zone D) Decrease in probe frequency - Decrease in probe frequency-the other options are inversely proportional to the transmitted frequency