SPI

What does this image demonstrate? A . Presence of flowB . Direction of flowC . Color aliasingD . Color inversionView AnswerAnswer: C Explanation: Color aliasing in Doppler ultrasound occurs when the velocity of blood flow exceeds the Nyquist limit, causing the color display to wrap around and display high velocities...

What improves the temporal resolution of color flow imaging?A . Decreasing pulse repetition frequencyB . Increasing ensemble length (packet size)C . Decreasing width of the color field of viewD . Increasing number of color lines per frameView AnswerAnswer: C Explanation: Temporal resolution refers to the ability of the ultrasound system...

Which factor has a positive effect on temporal resolution?A . Increase in scan depthB . Use of spatial compoundingC . Increase in number of focal zonesD . Use of narrow sector widthView AnswerAnswer: D Explanation: Temporal resolution refers to the ability to accurately depict moving structures over time. A narrow...

Which change improves temporal resolution during color flow imaging?A . Increase field of viewB . Decrease transmit frequencyC . Decrease packet sizeD . Increase line densityView AnswerAnswer: C Explanation: Temporal resolution is improved by increasing the frame rate. One way to increase the frame rate is by decreasing the packet...

What is the relationship between overall gain and image brightness?A . The higher the overall gain, the brighter the imageB . The lower the overall gain, the brighter the imageC . The higher the overall gain, the darker the imageD . There is no relationship between overall gain and image...

Which unfocused transducer will have the greatest divergence?A . 4 mm aperture, 4 MHzB . 4 mm aperture, 6 MHzC . 6 mm aperture, 4 MHzD . 6 mm aperture, 6 MHzView AnswerAnswer: A Explanation: Transducer beam divergence is influenced by the aperture size and frequency. A smaller aperture and...

Which type of structure is best visualized with low persistence?A . AnechoicB . StaticC . EchogenicD . DynamicView AnswerAnswer: D Explanation: Low persistence is best used for visualizing dynamic structures. Persistence is a setting that controls the averaging of successive frames to reduce noise and improve image quality. While high...

What occurs when the pulse repetition frequency is less than twice the Doppler shift frequency?A . Spectral broadeningB . Range ambiguityC . AliasingD . Propagation speed artifactView AnswerAnswer: C Explanation: Aliasing occurs in Doppler ultrasound when the pulse repetition frequency (PRF) is less than twice the Doppler shift frequency (Nyquist...

Which adjustment will reduce the artifact in the cystic lesion in image A resulting in image B? A . Turn off harmonicsB . Increase dynamic rangeC . Turn on edge enhancementView AnswerAnswer: C Explanation: Edge enhancement is a processing technique used in ultrasound imaging to improve the visibility of the...

Which parameters determine the propagation speed of sound in a medium?A . Frequency and impedanceB . Amplitude and impedanceC . Intensity and densityD . Elasticity and densityView AnswerAnswer: D Explanation: The propagation speed of sound in a medium is determined by the medium's elasticity and density. Elasticity refers to the...