Talk about a bad hair day: Japanese researchers have found that powdered hair thickeners can pose a problem when it comes to MRI exams, according to a poster presented at the recent virtual International Society for Magnetic Resonance in Medicine (ISMRM) meeting.
A team led by Dr. Norio Hayashi of Gunma Prefectural College of Health Sciences in Maebashi discovered that some powdered hair thickeners contain magnetic materials that can cause image artifacts on MRI.
"[We found that] there were some types of leave-on powdered hair thickener that do contain magnetic materials," Hayashi and colleagues wrote. "They [caused] more image artifacts ... and must be removed before the examination."
The use of leave-on powdered thickeners to address thinning hair as an alternative to wigs has increased, the researchers noted. But there have been limited studies on the mechanical effects or image artifacts caused by these products during MRI exams.
One of these was a 2017 study published in the journal Magnetic Resonance Imaging that reported that "a leave-on powdered hair thickener caused significant image artifacts," and suggested that MRI imaging facilities include questions about metal- or mineral-based hair products in screening protocols.
To explore the issue, Hayashi and colleagues evaluated 17 different leave-on powdered hair thickeners from seven different vendors for attraction force and MRI image artifacts. Of these 17 products, nine were "hair thickener types" and eight were "foundation types." The team measured displacement force and MRI artifacts using American Society for Testing Materials (ASTM) standards.
The study used both 1.5-tesla and 3-tesla MRI systems to assess phantoms that contained 10 g of each powder with T1-weighted images by spin-echo sequence and T2*-weighted images by gradient-echo sequence.
The powders caused no mechanical effects or artifacts on the MRI exam with the hair thickener-type products, but foundation-type products did cause mechanical effects and artifacts.
The takeaway? It's worth asking patients if they have thickening powder in their hair before the MRI exam.
"The leave-on powdered hair thickener that contains magnetic material is highly susceptible to mechanical effects and will cause more image artifacts, so it must be removed before the examination," the group concluded. "The MRI technologist should check the type of powdered hair thickener before the examination and take appropriate action if necessary."