MRI thermal burn injury: an unrecognized consequence of wearing novel, high-tech undergarments

This is the authors' abstract. We don't add key points for this paper.

Generally speaking, nuclear magnetic resonance imaging does not have any known effects on clothing materials. However, some new functional underwear have a potential of thermal burn injuries. Adequate preparation, including an awareness of the risks of functional underwear, is necessary prior to magnetic resonance imaging. Nuclear magnetic resonance imaging (MRI) is considered a standard diagnostic examination with minimal effects on the human body. Generally speaking, MRI does not have any known effects on clothing materials. However, previous studies have identified several thermal injuries associated with MRI.1–4 Here, we report a unique case of thermal burn injury caused by novel Japanese underwear technology. An 80-year-old woman complained of an unexplained, continuous, sunburn-like sensation on her back after undergoing MRI as part of an investigation of lower back pain during a very cold winter season in Shimane. She reported a severe sensation of heat, similar to hot steam, on her upper dorsal trunk and particularly on the skin surface in contact with the MRI table. This sensation began 5 min after a standard MRI protocol was initiated, and she appealed to the staff because she found the sensation as unendurable as an excessively hot bath. After a careful investigation, however, the staff re-started the procedure because the patient had undergone a complete routine check-up before MRI, which revealed no abnormalities in her body and MRI scanner. Two days after the MRI, the patient visited the hospital with the complaint of a burning, sunburn-like sensation on her back and consulted with orthopaedists and a neurologist. These physicians could not identify any diseases such as peripheral neuropathy or dysesthesia because her sensations could not be explained anatomically and she had no apparent dermatological abnormalities. Generally, her health was good and she had no medical history other than chronic back pain. We carefully took her history and conducted a neurological examination. Her symptoms were clearly limited to the area that had been in contact with the MRI table, and no conspicuous burn site was observed (Figure 1A). She reported that she had worn four undershirts simultaneously during the MRI scan (Figure 1B). A laboratory analysis revealed only slightly elevated creatine kinase (262 IU/l) and lactate dehydrogenase (254 IU/l) levels; all other test results were normal. (A) One day after the completion of MRI of the patient’s lumbar spine, no obvious dermatological findings were observed. However, a marked hyperesthesia-like area similar in appearance to a sunburn was observed, particularly in the centre of the ellipse. (B) The patient wore a total of four layers of novel underwear with Japanese heat-retardant technology during her imaging study. She reported wearing these undergarments during a follow-up appointment. While determining the final diagnosis, we wondered whether the new heat-retardant underwear available in Japan might cause of thermal burn injuries when worn during MRI scans. Accordingly, we contacted customer service of the manufacturer about the possibility of thermal burn development during MRI. The service responded that some hospitals had reported such cases. In addition, many Japanese-language reports in the literature (but no English-language reports) describe a relationship between these new undergarments and MRI. According to the manufacturer these undergarments comprise a woven fabric of acrylic (which shows high heat retention) and rayon (which shows high water and vapour absorption), with a concrete composition of 38% polyester, 34% acrylic, 18% rayon and 10% polyurethane (i.e. no metallic components). However, the functional underwear may absorb a large amount of water without subsequent evaporation. Additionally, the fabric has excellent heat-retention capabilities. Consequently, increases in surface temperature are more likely to occur, leading to a higher likelihood of thermal burns. The patient in this case recovered quickly and fully, without any sequelae. However, this case suggests that adequate preparation, including an awareness of the risks of functional underwear, is necessary prior to MRI, especially in light of increases in the magnetic field strength.5 Consent was obtained from the patient prior to the submission of this case report. The authors thank Professor Kazumichi Onigata of the Postgraduate Clinical Training Centre at Shimane University Hospital for his careful supervision of young physicians. Conflict of interest: None declared.