Inhomogeneity artifact
Citation, DOI, disclosures and article data
At the time the article was created Jose Miguel Alvarez Vera had no recorded disclosures.
View Jose Miguel Alvarez Vera's current disclosuresAt the time the article was last revised Amanda Er had the following disclosures:
- Radiopaedia Events Pty Ltd, Speaker fees (past)
These were assessed during peer review and were determined to not be relevant to the changes that were made.
View Amanda Er's current disclosuresThe inhomogeneity artifact is a type of magnetic resonance imaging artifact that occurs due to multiple factors, such as irregular anatomical area (for example, shoulder, hips, ankles), presence of metallic objects or inhomogeneity of the main field.
The inhomogeneity artifact appears as hyperintense or high signal in some fat-suppressed sequences that depend on the main field (i.e. SPIR or SPAIR).
The main problem with this artifact is that it can simulate edema or subcutaneous cellulitis. The use of sequences that do not depend on the homogeneity of the main magnetic field is highly recommended.
Remedy
can be fixed by using shimming coils in exam planning (at the center of FOV acquisition)
checking patient and MRI gantry before starting the exam, removing metallic elements or items with magnetic susceptibility
using STIR sequences instead of fat-saturation techniques that may have major sensitivity to inhomogeneity
References
- 1. Magnetic homogeneity [Internet]. Questions and Answers in MRI. 2022 [cited 22 June 2022]. Available from: https://mriquestions.com/why-homogeneity.html
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