1. The following sonogram shows air injected into the field of imaging. Which of the following is true:
A. The acoustic impedance of air is markedly high and therefore results in a strong echo reflection within soft tissue.
B. The acoustic impedance of air is markedly low and therefore results in a strong echo within soft tissue.
C. The acoustic impedance of air is markedly high and therefore results in no echo within soft tissue.
D. The acoustic impedance of air is markedly low and therefore results in no echo within soft tissue.
2. The artifact shown above is:
C. referred to as bayonet artifact because of the resemblance of the needle echoes to the shape of a bayonet.
3. The artifact shown above is:
A. caused by differences in attenuation of sound waves within the overlying soft tissue and blood vessels.
4. Given the image shown above (A), the transducer manipulation most likely (or necessary) to place the entire needle tip and shaft within the field of imaging (B) is (a small amount of):