Expanding the sector width while adjusting focal zones typically impacts which imaging parameter the most?

• A. Axial resolution
• B. Lateral resolution
• C. Temporal resolution
• D. Signal-to-noise ratio

Answer: (C)

Expanding the sector width makes each frame cover a wider angular area, so the system must send and process more scan lines per frame. When you also adjust focal zones, you often introduce additional transmit events to maintain focus at multiple depths. All of this increases the amount of data and time required to form a single frame, which lowers how many frames can be produced each second. That drop in frame rate directly reduces temporal resolution—the ability to track rapid changes over time.

Axial resolution is mainly determined by pulse length and frequency, not by how wide the sector is. Lateral resolution depends on beam width and aperture, which aren’t the primary consequence of widening the sector in this scenario. Signal-to-noise ratio is influenced more by gain, averaging, and noise characteristics than by sector width or focal zone adjustments.