During the course of a sonographic exam, you notice lateral splaying of the echoes in the far field. What can you do to improve the image?

• A. Use the maximum acoustic power
• B. Use the lowest line density setting
• C. Increase the number of transmit focal zones and optimize their location
• D. Decrease the scanning depth

Answer: (C)

Lateral splaying in the far field happens when the beam isn’t narrowly focused as it travels, so echoes spread out and the image loses lateral resolution. The best way to tighten the beam across depths is to increase the number of transmit focal zones and place their focal points where you need detail—typically near the region of interest or at multiple depths. This keeps the beam width narrow at those depths, reducing the splaying and improving the clarity of structures far away. Just keep in mind that adding more focal zones can lower frame rate due to longer focusing, but it’s the most effective way to improve lateral resolution. Increasing power won’t fix this and can raise patient exposure; lowering line density reduces detail, and decreasing depth is sometimes useful but doesn’t target the wide-field focusing as directly as optimizing focal zones.