Magnets for therapy in the GI tract: a systematic review

1 In 1957, Equen et al reported the retrieval of foreign bodies in the esophagus, stomach, and duodenum by using magnets. For many years afterward, the clinical role for magnets and magnetic technologies in the GI tract remained quiescent. However, recently there has been a resurgence of interest. Advanced endoscopic therapeutic techniques such as natural orifice transluminal endoscopic surgery (NOTES) and endoscopic anastomosis creation have been developed as a minimally invasive alternative to surgery. Although these techniques reduce hospital stay, recovery time, and adverse events associated with conventional surgery, their wider uptake has been slow. This is in part due to the complex and demanding nature of the techniques, requiring a highly skilled operator. Difficulties often are encountered with tissue traction, anchoring, and accuracy of dissection as a result of a lack of triangulation of instruments and distal force transmission. The properties of magnets may present a technological solution to some these challenges. Their ability to exert untethered force over distance means magnets could be used in endoluminal resections and coupling and anchoring for singleincision laparoscopy as well as in NOTES procedures. In addition, applications to specific clinical indications have resulted in the advancement of magnetic compression anastomosis and sphincter augmentation, which are already clinically demonstrated. The endoscopic and surgical communities have traditionally perceived magnets with justified scepticism because of the widely recognized perils of magnet ingestion. Early successes with innovative therapeutic uses of magnets allowed clinicians to view magnets differently, as