The document discusses various ultrasound artifacts, which are distorted images that do not accurately represent the examined part. It categorizes artifacts into types such as reverberation, acoustic shadowing, acoustic enhancement, and others, explaining their causes and implications. Understanding these artifacts is crucial for accurate diagnosis, as they can significantly affect image interpretation.

1. CHAPTER VIII:
ARTIFACTS

2. CHAPTER VIII
• An ultrasound artifact is an
additional, missing or distorted
image which does not conform to
the real image of the part being
examined.

3. CHAPTER VIII
• Different types of UTZ artifacts
1. Reverberation
2. Acoustic shadowing
3. Acoustic enhancement
4. Edge shadowing
5. Side lobe artifacts
6. Mirror image
7. Double image
8. Equipment-generated artifacts

4. CHAPTER VIII
1. REVERBERATION
• This is the production of spurious
(false) echoes due to repeated
reflections
• Comet tail

5. CHAPTER VIII
• Artifacts appearing as parallel, equally
spaced lines is called reverberation
• Reverberation artifacts are a result of
the presence of two or more strong
reflecting surfaces
• Shotgun wound

6. CHAPTER VIII
2. ACOUSTIC SHADOWING
• This appears as an area of low
amplitude echoes (hypoechoic or
anechoic) behind an area of strongly
attenuating tissue.

7. CHAPTER VIII
• If the shadowing contains ringdown
echoes, it is likely to be gas.
• If the shadowing is clear shadowing,
absent of any ringdown, it is likely to be
a calculus
• Calcified mass

8. CHAPTER VIII
3. ACOUSTIC ENHANCEMENT
• This artifact appears as a localized
area of increased echo amplitude
behind an area of low attenuation.

9. CHAPTER VIII
• Can commonly be seen distal to fluid filled
structures such as the urinary bladder, the
gallbladder or a cyst.

10. CHAPTER VIII
• Acoustic enhancement is caused
by weakly attenuating structures.
• Fluid filled mass

11. CHAPTER VIII
4. EDGE SHADOWING
• Occurring at the edges of rounded
structures will result in an edge
shadowing artifact.

12. CHAPTER VIII
5. SIDE LOBE ARTIFACT
• The energy within the ultrasound beam
exists as several side lobes radiating at a
number of angles from a central lobe.

13. CHAPTER VIII
6. MIRROR IMAGE ARTIFACT
• These artifacts result in a mirror image of a
structure.
• They arise due to specular reflection of
the beam at a large smooth interface.

14. CHAPTER VIII
• fluid-air interface.
• Diaphragm, Heart, Liver

15. CHAPTER VIII
7. DOUBLE IMAGE ARTIFACT
• This artifact is caused by refraction of the
beam and may occur in areas such as the
rectus abdominis muscle on the anterior
abdominal wall.

16. CHAPTER VIII
• In order to establish whether these echoes
are genuine, it is necessary to move the
transducer slightly to one side to avoid the
junction of the rectus abdominis muscles.

17. CHAPTER VIII
8. EQUIPMENT-GENERATED ARTIFACTS
• Incorrect use of the equipment controls can
lead to artifacts appearing.

18. CHAPTER VIII
• If too much gain is applied then the
electronic noise, inherent in all systems, will
also be amplified.
• If too little gain is applied, this can lead to
loss of relevant information, and incorrect
diagnosis may occur.

19. CHAPTER VIII
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