ARDMS SPI Image Formation and Processing 2

Question 1

What is the primary function of the scan converter in a diagnostic ultrasound system?

Accepted Answer

Convert polar ultrasound data into a rectangular display format

Answer

The scan converter maps echo data from the polar coordinate geometry of the transducer sweep into the Cartesian (rectangular) format used by the video display.

Question 2

Which parameter directly determines the number of pixels used to represent a digital ultrasound image?

Accepted Answer

Matrix size

Answer

Matrix size (e.g., 512×512 or 1024×1024) defines the total number of pixels in the digital image grid.

Question 3

In digital ultrasound imaging, bit depth refers to:

Accepted Answer

The number of bits used to encode the gray-scale value of each pixel

Answer

Bit depth determines how many distinct gray levels can be represented; 8-bit depth yields 256 gray levels.

Question 4

Frame rate in real-time ultrasound imaging is primarily limited by:

Accepted Answer

The speed of sound and imaging depth

Answer

Because sound must travel to the maximum depth and return before the next pulse is fired, greater depth forces a lower pulse repetition frequency and thus a lower frame rate.

Question 5

What happens to frame rate when the number of scan lines per frame is increased while imaging depth remains constant?

Accepted Answer

Frame rate decreases

Answer

More scan lines require more pulses per frame, which increases the time needed to build each image and therefore reduces frame rate.

ARDMS SPI - ARDMS Sonography Principles and Instrumentation Practice Test

ARDMS SPI - ARDMS Sonography Principles and Instrumentation Practice Test

ARDMS SPI Image Formation and Processing 2