Endoscopic Clip MRI Screening: A Canada-Wide Policy Survey

Not all endoscopically placed clips are MRI compatible, so screening for endoscopic clips before MRI is recommended. The purpose of this study was to assess endoscopic clip screening practices at Canadian MRI centers, including number of centers that screen, specific screening methods, perceived safety of endoscopic clip models, and practices for dealing with confirmed gastrointestinal endoscopic clips.

A bilingual online survey was distributed to Canadian MRI centers to assess site demographics, endoscopic clip screening practices, safety considerations for different endoscopic clip models, protocols for dealing with patients with endoscopic clips, and the perceived value of screening. One year later, a secondary survey was distributed to the original participants to assess for changes made to screening policy after the initial survey and to assess awareness of any complications arising from the presence of endoscopic clips during MRI.

Sixty-seven MRI centers completed the survey (55% response rate). Sixteen centers (24%) did not specifically screen for endoscopic clips, five because they were not aware that endoscopic clips may not be safe for MRI. Fifty-one centers (76%) did screen for endoscopic clips. At least 23% of screeners misclassified the safety of one or more MRI-unsafe clips. As many as 36% of screeners may perform MRI on patients with confirmed gastrointestinal endoscopic clips; 16% reschedule for more than 6 weeks after endoscopy; and 18% limit the field strength to 1.5 T, the safety of which is uncertain.

Many Canadians are undergoing MRI without screening for endoscopic clips. Although the risks of MRI to patients with endoscopic clips is unclear, the misclassification of some endoscopic clip models and inconsistent protocols for dealing with confirmed endoscopic clips call for further research and unified evidence-based endoscopic clip screening standards.