Which artifact may cause both axial and lateral displacement of a reflector on the image?

Which artifact may cause both axial and lateral displacement of a reflector on the image?

• A. Refraction
• B. Side lobe
• C. Multipath reflections
• D. Partial volume

Answer: (C)

Multipath reflections occur when the ultrasound energy takes more than one path to or from a reflector, such as bouncing between boundaries or following a tilted route. Because the echo’s travel path and angle are altered, the system’s depth calculation and beam-positioning place the echo at an incorrect location. That means the reflector can appear displaced both along the axis of the beam (axial) and across the image (lateral). This combination of depth and positional error is why multipath reflections can shift a reflector in two dimensions on the image. Refraction mainly causes lateral misregistration by bending the beam at interfaces with different speeds, rather than true axial displacement. Side lobe artifacts come from off-axis energy producing spurious echoes that don’t represent the actual reflector’s position. Partial volume artifacts blur or mix tissue signals within a voxel, reducing detail but not typically producing a precise shift of a single reflector in both directions.

Multipath reflections occur when the ultrasound energy takes more than one path to or from a reflector, such as bouncing between boundaries or following a tilted route. Because the echo’s travel path and angle are altered, the system’s depth calculation and beam-positioning place the echo at an incorrect location. That means the reflector can appear displaced both along the axis of the beam (axial) and across the image (lateral). This combination of depth and positional error is why multipath reflections can shift a reflector in two dimensions on the image.

Refraction mainly causes lateral misregistration by bending the beam at interfaces with different speeds, rather than true axial displacement. Side lobe artifacts come from off-axis energy producing spurious echoes that don’t represent the actual reflector’s position. Partial volume artifacts blur or mix tissue signals within a voxel, reducing detail but not typically producing a precise shift of a single reflector in both directions.