Two major types
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Technique-dependent artifacts:
 Noise caused by excess gain
Resolving noise caused by excess gain
- Decrease overall gain
Low signal caused by inappropriate transducer selection or low gain settings
Resolving low gain artifacts:
- Increase overall gain
- Increase far gain
- Apply more acoustic coupling gel
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Inherent sonographic artifacts
Shadowing
Caused by sound striking a strong reflective interface example; areas behind ribs or gall stones
Shadowing corrective technique:
- Scan around object causing shadowing
Enhancement
Caused by sound travelling through fluid-filled structures without attenuation (example: area behind cysts, area behind gallbladder)
Enhancement corrective technique:
- Reduce overall gain
- Decrease far gain
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Reverberation
Caused by sound interfacing with two structures of markedly differing acoustic properties;
example: inadequate amount of gel, obstructing bowel gas
Reverberation corrective technique:
- Change angle of transducer
- Apply more gel
- Rotate patient |
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ArticleDate:20041123
SiteSection: Article
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