Presentation
Chronic headache. Artifact on MRI scan. Patient sent home to wash hair and returned for repeat imaging.
Patient Data
Age: 45 years
Gender: Female
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Susceptibility artifact in the left anterior scalp that disappears after the hairwash. Similar artifact associated with falcine ossification remains unchanged.
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The artifact is no longer present.
Case Discussion
Dry shampoo is used to remove grease from unwashed hair and contains:
- cornstarch: to bind fatty acids
- kaolin: to absorb grease
- Laminaria saccharina (type of seaweed) extract: anticlumping agent to reduce caking of the cornstarch and kaolin
- magnesium stearate: also an anticlumping agent
- denatured alcohol: solvent for the cornstarch and kaolin
- liquefied petroleum gas: propellant for the spray can
The kaolin, cornstarch and magnesium may all cause artifacts due to local magnetic field distortion, most prominently seen on the echo-planar sequences, i.e. DWI and SWI.