Which factor least influences lateral resolution?

Which factor least influences lateral resolution?

• A. Beam width
• B. Frequency
• C. Focus depth
• D. Damping

Answer: (D)

Lateral resolution depends on how wide the ultrasound beam is as it travels through tissue—the narrower the beam, the better the ability to distinguish objects side by side at a given depth. Beam width is directly shaped by the frequency and by focusing. Higher frequency yields a shorter wavelength and, when combined with focusing, tightens the beam, improving lateral resolution. Focus depth narrows the beam at the focal region, enhancing lateral resolution there. Damping, on the other hand, mainly affects the time-domain signal and bandwidth, which determine axial resolution (along the beam) rather than the width of the beam in the lateral plane. So damping has the least influence on lateral resolution.

Lateral resolution depends on how wide the ultrasound beam is as it travels through tissue—the narrower the beam, the better the ability to distinguish objects side by side at a given depth. Beam width is directly shaped by the frequency and by focusing. Higher frequency yields a shorter wavelength and, when combined with focusing, tightens the beam, improving lateral resolution. Focus depth narrows the beam at the focal region, enhancing lateral resolution there. Damping, on the other hand, mainly affects the time-domain signal and bandwidth, which determine axial resolution (along the beam) rather than the width of the beam in the lateral plane. So damping has the least influence on lateral resolution.