When the sound beam is refracted during a sonographic examination which of the following might you detect on the ultrasound image?

When the sound beam is refracted during a sonographic examination which of the following might you detect on the ultrasound image?

• A. Axial misregistration
• B. Lateral misregistration
• C. Reverberations posterior to a reflector
• D. Enhancement of a reflector

Answer: (B)

When a sound beam crosses a boundary where the propagation speed changes, it bends. If the boundary isn’t perpendicular to the beam, that bending shifts the path sideways, so the structure ends up appearing in a different lateral position than it truly is. That lateral shift is what we call lateral misregistration on the image. Axial misregistration would involve depth displacement along the beam path, not sideways bending. Reverberations behind a reflector come from multiple internal reflections, not refraction, and enhancement behind a reflector is due to attenuation differences, not beam bending. So refraction most directly produces a lateral misregistration on the image.

When a sound beam crosses a boundary where the propagation speed changes, it bends. If the boundary isn’t perpendicular to the beam, that bending shifts the path sideways, so the structure ends up appearing in a different lateral position than it truly is. That lateral shift is what we call lateral misregistration on the image. Axial misregistration would involve depth displacement along the beam path, not sideways bending. Reverberations behind a reflector come from multiple internal reflections, not refraction, and enhancement behind a reflector is due to attenuation differences, not beam bending. So refraction most directly produces a lateral misregistration on the image.