Which imaging mode plots depth along the horizontal axis and amplitude along the vertical axis, typically used for measurement along a line?

Which imaging mode plots depth along the horizontal axis and amplitude along the vertical axis, typically used for measurement along a line?

• A. A-Mode
• B. B-Mode
• C. M-Mode
• D. C-Mode

Answer: (A)

A-mode displays echoes as spikes along a depth axis, with depth on the horizontal axis and amplitude (echo strength) on the vertical axis. This single-line, one-dimensional plot makes it ideal for precise measurements along a line, such as determining the distance to interfaces or measuring ocular axial length. The height of each spike corresponds to how strong the reflected signal is at that depth, so you can quantify exact positions of interfaces along that line. Other imaging modes serve different purposes. A two-dimensional grayscale image (B-mode) maps depth and lateral position with brightness representing echo strength, not a simple depth-versus-amplitude plot. A mode records how echoes at a single line change over time, effectively depth plotted against time to show motion. C-mode represents a different type of depth-related mapping used in specialized applications and doesn’t provide the straightforward depth-versus-amplitude line measurement that A-mode offers.

A-mode displays echoes as spikes along a depth axis, with depth on the horizontal axis and amplitude (echo strength) on the vertical axis. This single-line, one-dimensional plot makes it ideal for precise measurements along a line, such as determining the distance to interfaces or measuring ocular axial length. The height of each spike corresponds to how strong the reflected signal is at that depth, so you can quantify exact positions of interfaces along that line.

Other imaging modes serve different purposes. A two-dimensional grayscale image (B-mode) maps depth and lateral position with brightness representing echo strength, not a simple depth-versus-amplitude plot. A mode records how echoes at a single line change over time, effectively depth plotted against time to show motion. C-mode represents a different type of depth-related mapping used in specialized applications and doesn’t provide the straightforward depth-versus-amplitude line measurement that A-mode offers.