オノ　アツシ   Atsushi Ono   小野　敦    所属   川崎医療福祉大学  医療技術学部 診療放射線技術学科    職種   教授
言語種別	英語
発表タイトル	Effect of electromagnetic wave suppression sheet in magnetic resonance imaging system on radio-frequency-induced heating of the metallic implant
会議名	The 46th Annual Meeting of the Japanese Society for Magnetic Resonance in Medicine
学会区分	全国規模の学会
発表形式	口頭
講演区分	一般
発表者・共同発表者	◎Atsushi Ono, Shinichi Arao, Satoru Takata, Akihiko Tabuchi, Norio Yoshizaki, Yuki Ando
発表年月日	2018/09/08
開催地 （都市, 国名）	Kanazawa City, Japan
概要	Radio-frequency-(RF)-induced heating in magnetic resonance imaging (MRI) may pose risks to patients with metallic implants. Electromagnetic wave suppression sheet (EWS-sheet) is a promising tool to suppress RF-induced heating. To date, there is no data that conclusively proves that EWS-sheets prevent temperature increase in metallic implants. The purpose of this study was to assess the effect of EWS-sheets on attenuation of RF-induced heating of conductive implants in MRI and investigate appropriate methods of covering the implants with EWS-sheets that enable reduction of temperature increase. The effect of using the EWS-sheet to deter RF-induced heating depends on the covering method and placement. By ensuring adequate overlap in the parallel direction, full and half covering allowed the implant to resist heating within safety limits. It was noted that deficient overlapping in the parallel direction and a large vertical space between the sheet and implant caused higher temperature increase in the implant than in cases without use of the EWS-sheet, as a result of enhancement of RF power and incident RF pulses. EWS-sheets may be useful for protecting patients with conductive implants from the risks of RF-induced heating. Further investigations are needed to define the safety guidelines more precisely.