In B-mode, which axis represents side-to-side or superior/inferior aspects of the body?

In B-mode, which axis represents side-to-side or superior/inferior aspects of the body?

• A. X axis
• B. Y axis
• C. Z axis
• D. Time axis

Answer: (A)

In B-mode imaging, the display is a two-dimensional map of echoes from a scanned plane. The beam sweeps across the transducer to form scan lines from left to right, so the horizontal dimension on the screen corresponds to side-to-side (lateral) positions in that plane. The vertical dimension represents depth into the body (how far echoes originate from the transducer). Therefore, the axis that carries side-to-side information is the horizontal axis, i.e., the X axis. Time is not an anatomical axis; it’s just used for cine loops to record frames over time.

In B-mode imaging, the display is a two-dimensional map of echoes from a scanned plane. The beam sweeps across the transducer to form scan lines from left to right, so the horizontal dimension on the screen corresponds to side-to-side (lateral) positions in that plane. The vertical dimension represents depth into the body (how far echoes originate from the transducer). Therefore, the axis that carries side-to-side information is the horizontal axis, i.e., the X axis. Time is not an anatomical axis; it’s just used for cine loops to record frames over time.