Ultrasound Physics II Practice Exam

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• What does static imaging display?
• PACS in medical imaging refers to?
• Frame Rate is defined as:
• In real-time imaging, which description best fits?
• What is the Doppler Effect in ultrasound context?
• How does frame-to-frame coherence affect speckle, and how can averaging or persistence alter it?
• Enveloping is the result of which demodulation stage?
• A picture element is known as which term?
• Temporal Compounding in ultrasound imaging results in?
• In deep imaging, frame rate is:
• What is the purpose of the Reject receiver function?
• In deep imaging, what sector size is used?
• What is the typical frequency-attenuation relationship in soft tissue, and what is α at 1 MHz?
• Which target is considered stationary for frame rate considerations?
• In Doppler ultrasound, which statement best describes aliasing and the Nyquist limit?
• Which imaging approach offers superior temporal resolution?
• Deep imaging frame rate is typically:
• The Nyquist frequency is half of the PRF. If PRF increases, what happens to Nyquist frequency?
• If RBC velocity doubles, the Doppler shift will
• Which statement about speckle is true?
• In 3D/4D ultrasound, what is a voxel and how is volume data constructed?
• A pixel is defined as which of the following?
• The Doppler Shift helps determine which property?
• If time-of-flight measurement has an error Δt, how does depth error Δd relate?
• For moving heart imaging, what is the line density?
• How do phased-array and single-element transducers differ in beamforming?
• Narrow Dynamic Range yields which display characteristic?
• Higher line density has what effect on spatial information?
• Increasing the transducer aperture size D has what effect on beam divergence in the far field?
• What is the function of the matching layer in a transducer?
• What is the key difference between fundamental and harmonic imaging regarding tissue interaction?
• Dynamic Range is measured in which unit?
• In color Doppler velocity estimation, why does angle dependence limit accuracy?
• What is a key feature of harmonic imaging?
• For deep imaging, increasing PRP results in PRF...?
• Increasing the number of scan lines per frame will primarily improve which aspect?
• Which term describes a broad dynamic range in display terms?
• When RBCs move toward transducer, observed frequency is?
• What does the receiver do?
• High line density tends to influence frame rate and spatial resolution. Which pairing is correct?
• What are the two common ultrasound artifacts shadowing and enhancement, and what causes them?
• Frame rate units are:
• In soft tissue, the speed of sound is approximately 1540 m/s. If a 5 MHz transducer is used, what is the wavelength in tissue?
• Frame rate is inversely related to image creation time. Options:
• Time delay corresponds to which?
• ALARA principle involves minimizing exposure by adjusting which ultrasound system parameter?
• Which condition yields a higher frequency shift?
• Temporal resolution is highest in which imaging depth?
• In deep imaging, what is the line density?
• In receiver functions, amplification is equivalent to which concept?
• In shallow imaging, the frame rate is:
• Which statement correctly characterizes digital signals in imaging?
• How does wall filtering improve color Doppler quality, and what Doppler components does it target?
• Compared to deep imaging, the go-return time in shallow imaging is:
• Which processing step occurs after data storage in imaging workflows?
• In Doppler ultrasound, the measured shift is proportional to cos θ. If θ increases toward 90°, the Doppler shift:
• What is the Nyquist frequency in Doppler imaging relative to PRF?
• DICOM is best described as?
• Which statement best expresses the relationship between frame rate and time per frame?
• What are side lobes and grating lobes in an array, and how do they affect image quality?
• Time-Velocity Integral (TVI) in Doppler ultrasound is used to estimate what?
• ALARA stands for which full name?
• Specular reflection and scattering: which statement correctly differentiates them?
• Which of the following describes how the time needed to create a frame changes with increasing frame rate?
• How is the mechanical index (MI) defined, and what does it indicate?
• PRP is an acronym for what term?
• The sign used for movement away from the transducer is?
• Which imaging depth uses a small sector size?
• What tissue property enables harmonic imaging to generate harmonics?
• In shallow imaging, temporal resolution is described as:
• What is the significance of 1540 m/s as the speed of sound in tissue?
• In tissue harmonic imaging, which frequency configuration is used and what is the purpose of filtering?
• The reflection coefficient for intensity at an interface is 0.10. What percent of the incident acoustic intensity is reflected?
• Which method is an effective way to mitigate aliasing in Doppler spectra?
• If RBCs move away from the transducer, observed frequency is?
• Wide Dynamic Range corresponds to which display characteristic?
• What term denotes the smallest unit of a digital image?
• With speed of sound 1540 m/s in tissue and frequency 3 MHz, what is the wavelength?
• Shadowing artifact is commonly produced by what structure?
• Define tissue harmonic imaging and state one key benefit.
• If frame rate increases, what happens to the time needed to make a frame?
• For low line density, what combination of frame rate and spatial resolution results?
• Frequency Compounding in ultrasound imaging achieves what?
• Which artifacts are associated with speed mismatch at an interface?
• Dynamic Range connects directly to which receiver function?
• What is the purpose of phantom calibration in ultrasound?
• A narrow sector typically results in which combination of frame rate and temporal resolution?
• What is pulse length and how does it affect axial resolution and sensitivity?
• For moving structures such as the heart, which focus setting is used?
• A single binary digit is called what?
• Real-Time imaging displays:
• A CW Doppler uses a 4 MHz transducer to measure flow at θ = 60°. If the blood velocity is 50 cm/s, what is the Doppler shift in Hz?
• Which statement correctly describes Narrow Dynamic Range?
• What makes microbubble contrast agents enhance ultrasound signals?
• Negative Doppler Shift occurs when RBCs move away from transducer, resulting in?
• Which processing step occurs before storage in imaging data workflows?
• Which standard governs medical image communication?
• Which option is NOT a function of the receiver?
• In deep imaging, temporal resolution is described as:
• For moving heart, frame rate is typically?
• What is the principal mechanism by which tissue harmonic imaging reduces clutter?
• In Doppler ultrasound, what does the Time-Velocity Integral (TVI) display estimate?
• What causes speckle in ultrasound images, and how does it affect image interpretation?
• What is the difference between SPTP and SPTA intensities, and which is used for calculating thermal indices?
• If RBC velocity increases, Doppler shift?
• Acoustic impedance is defined as Z = ρ c and has units Rayl. Which expression gives the pressure reflection coefficient at normal incidence between two media with impedances Z1 and Z2?
• In ultrasound speckle, what distribution describes echo amplitudes, and what does it imply about intensities?
• Which aspect of imaging data is affected by the bit value, beyond representing 0 or 1?
• Which statement correctly describes the relationship between PRF and PRP?
• If frequency doubles from 2 MHz to 4 MHz, what is the change in attenuation over 5 cm if α is 0.5 dB/(cm·MHz)?
• In deep imaging, what focusing method is used?
• Which statement is true about gallbladder vs heart imaging?
• What are ghost echoes and what causes them?
• A bit is best described as which of the following?
• Amplification in the receiver context corresponds to which term?
• Which term reduces noise by combining sub-bands?
• What is the principle behind dynamic aperture and its effect on lateral resolution at depth?
• What information does spectral Doppler provide compared with color Doppler?
• In shallow imaging, line density is:
• To achieve better spatial resolution, which frame rate would you typically accept?
• What is the consequence of using fewer scan lines?
• Which factor can reduce frame rate in this imaging setup?
• In Doppler ultrasound, PRF stands for pulse repetition frequency. How does increasing PRF affect Nyquist limit and potential aliasing, assuming depth is adjusted as needed?
• Which statement correctly contrasts Color Doppler and Power Doppler in terms of velocity information and sensitivity?
• Why does tissue harmonic imaging typically prefer receiving at 2f0 (twice the transmitted frequency)?
• In deep imaging, go-return time is:
• Doppler shift provides information about what in flow?
• Define axial and lateral resolution in ultrasound and describe how to improve each.
• Which of the following factors improves lateral resolution in ultrasound imaging?
• Which component is not a function of the pulser or the receiver?
• Which statement differentiates strain imaging from shear-wave elastography?
• What is a typical FDA safety index range for diagnostic ultrasound in terms of MI and TI?
• Stationary structures like the gallbladder typically use which focus setting?
• Which option best represents ALARA's recommended adjustment to minimize exposure?
• Temporal Compounding is defined as?
• What is a typical guidance value for the Thermal Index (TI) in diagnostic ultrasound?
• If the measured sound speed c_meas differs from the true speed c by Δc, which expression best describes the resulting depth error Δd?
• Which of the following expresses the unit for the attenuation coefficient in soft tissue?
• Which term is used to describe the ratio of the largest to smallest signal?
• For moving structures such as the heart, what combination yields high frame rate according to HEART = SPEED?
• In the context of stationary structures, to which attribute is STATIONARY equal?
• In stationary gallbladder imaging, what is the frame rate?
• If all other factors are constant, what happens to the mechanical index as transmit frequency increases?
• For stationary gallbladder structures, what is the field of view (FOV) used?
• Which statement is true regarding preprocessing and postprocessing with respect to storage?
• Dynamic Range has a direct relationship with which function?
• Demodulation by rectification primarily does what to the signal?
• Narrow Dynamic Range is also called which term?
• Which statement about stationary gallbladder imaging is true?
• In shallow imaging, sector size is:
• In tissue harmonic imaging, what is the role of filtering in the received signal?
• The Doppler shift in ultrasound is primarily caused by the motion of which entities?
• Which technique averages frames from different viewpoints?
• If Time per frame is 0.02 seconds, the Frame Rate is:
• Which ultrasound imaging enhancement improves signal-to-noise ratio and resolution?
• Doppler shift is most directly related to which velocity?
• In 3D/4D ultrasound, what additional dimension does 4D data introduce?
• Which operation removes weak signals?
• In stationary gallbladder imaging, what is the line density?
• Dynamic range is defined as which of the following?
• Which expression represents the frame rate formula?
• If you double frame rate from 20 Hz to 40 Hz, what happens to frame time?
• HEART = SPEED: Which combination yields a high frame rate?
• A wide sector yields which combination?
• The product of frame time and frame rate implies what relationship?
• What is the expected effect of increasing transducer frequency on lateral resolution and attenuation?
• A 60 Hz display yields approximately how much time per frame?
• Which term describes signals with continuous values?
• Which term is associated with generating a three-dimensional representation from data?
• Which statement best describes a phased-array transducer?
• Increasing the number of scan lines has which effect?
• Demodulation by smoothing results in which effect?
• In receiver functions, compensation is equivalent to which concept?
• How does dynamic focusing improve beam quality with depth in ultrasound imaging?
• Positive Doppler Shift occurs when RBCs move toward transducer, resulting in?
• Static imaging is best described as:
• Which combination results in a low frame rate according to the material?
• Which factors influence frame rate in B-mode imaging?
• What is the effect of deep imaging on lateral resolution?
• For pulsed-wave Doppler, what is the Nyquist limit and how does it constrain measurable velocity?
• Which items are included in the receiver?
• As the Doppler angle approaches 90 degrees, what happens to velocity estimation?
• Which parameter most directly affects frame rate for moving heart imaging?
• Which statement correctly describes how to maximize frame rate in ultrasound, given practical constraints?
• For an ultrasound beam, the near-field length N is approximately N ≈ D^2/(4λ). If the aperture D increases while the wavelength λ remains the same, what happens to the near-field length?
• In shallow imaging, the focus is:
• Which statement about dynamic focusing is true?
• Differentiate acoustic streaming from physiologic perfusion.
• Derive the Doppler shift equation for motion along the ultrasound beam: Δf = ?
• Stationary Structure — Gallbladder uses which focus?
• The Doppler shift is proportional to which quantity?
• Which statement correctly characterizes analog signals in imaging?
• To maximize temporal resolution, which sector setting is preferred?
• Fill-In Interpolation in ultrasound imaging is used to?
• What is a consequence of poor impedance matching between the transducer and tissue?
• Spatial Compounding does what in ultrasound imaging?
• Which description best matches the effect of compression in ultrasound imaging?
• If PRP is decreased, what happens to PRF?
• If acoustic impedances Z1 and Z2 are equal, what is the pressure reflection coefficient at their interface?
• In moving structure imaging, which combination yields high frame rate?
• For moving heart imaging, what is the field of view?
• What effect does transducer curvature have on focusing and the near field?
• What is the function of the pulser?
• Edge Enhancement in ultrasound imaging serves to?
• In grayscale imaging, the bit value primarily influences which aspect?
• In shallow imaging, the go-return time is:
• If PRF = 5 kHz, f0 = 5 MHz, θ = 0°, c = 1540 m/s, what is the maximum detectable velocity?