Which imaging technique uses multiple focal zones during real-time imaging to improve lateral resolution?

Which imaging technique uses multiple focal zones during real-time imaging to improve lateral resolution?

• A. Multifocal imaging
• B. Monofocal imaging
• C. Doppler imaging
• D. Harmonic imaging

Answer: (A)

Focusing the beam at multiple depths narrows the acoustic beam at several locations, which sharpens side-to-side (lateral) resolution across the image. When real-time imaging uses several focal zones, each depth benefits from a tighter beam, so structures appear crisper throughout the field of view rather than only near a single focal point. This approach is called multifocal imaging. The trade-off is that more focal zones require additional transmissions, which lowers frame rate. Monofocal imaging uses just one focal depth, so the frame rate stays higher but lateral resolution is best only near that single focal point. Doppler imaging looks at motion and velocity, not at focal-zone strategy, and harmonic imaging improves resolution through tissue harmonics rather than through multiple focal zones.

Focusing the beam at multiple depths narrows the acoustic beam at several locations, which sharpens side-to-side (lateral) resolution across the image. When real-time imaging uses several focal zones, each depth benefits from a tighter beam, so structures appear crisper throughout the field of view rather than only near a single focal point. This approach is called multifocal imaging. The trade-off is that more focal zones require additional transmissions, which lowers frame rate. Monofocal imaging uses just one focal depth, so the frame rate stays higher but lateral resolution is best only near that single focal point. Doppler imaging looks at motion and velocity, not at focal-zone strategy, and harmonic imaging improves resolution through tissue harmonics rather than through multiple focal zones.