Assessment of metallic patient support devices and other items at 7-Tesla: Findings applied to 46 additional devices

Abstract

Objective: Recently, the first 7-Tesla MR system was approved for clinical use in Europe and the United States. Unfortunately, few metallic objects have undergone testing in association with this high-field-strength scanner, including essential equipment such as patient support devices and other items. Therefore, the objective of this investigation was to assess metallic patient support devices and other items for translational attraction at 7-Tesla.

Methods: Thirteen different metallic items (e.g., gurney, Mayo stand, step stool, utility table, wheelchair, etc.) underwent testing for translational attraction using a previously described methodology in association with a clinical 7-T MR system. The findings were categorized as pass (no translational attraction) or fail (the item was attracted by the scanner).

Results: Every metallic item tested exhibited a lack of magnetism while in a worst-case use position and, thus, passed the test for translational attraction in associated with the 7-Tesla MR system.

Conclusions: The different thirteen different metallic patient support devices and other items can be designated as MR Conditional at 7-T or less. Furthermore, because each item represented a worst-case with respect to its mass and the type of metallic material used for its fabrication, the results can be applied to 46 additional smaller items made from the same material or material with a lower magnetic susceptibility. This expanded list of essential patient support devices and other items will facilitate the clinical use of a comparable 7-Tesla scanner, or another UHF scanner with similar fringe field characteristics.

Keywords: 7-Tesla; MRI safety; Magnetic resonance imaging (MRI); Medical equipment; Ultra-high-field (UHF).