Interventional magnetic resonance (MR) techniques have evolved into clinically viable surgical and therapeutic applications. This has resulted in the development and performance of innovative procedures that include percutaneous biopsy (e.g., breast, bone, brain, abdominal, etc.), endoscopic surgery of the abdomen, spine, and sinuses, open brain surgery, and MR-guided monitoring of thermal therapies (i.e., laser-induced, RF-induced, and cryomediated procedures).

Surgical instruments and devices are an important necessity for interventional MR. Besides the typical MR safety concerns, there are possible hazards in the interventional MR environment related to the surgical instruments and devices that must be addressed to ensure the safety of healthcare practitioners and patients. Many of the conventional instruments and devices are made from metallic materials that can create substantial problems in association with interventional MRI.

The interventional MR safety issues that exist for surgical instruments and devices include unwanted movement caused by magnetic field interactions (e.g., the “missile effect”, translational attraction, torque), issues related to eddy currents, and heat generated by RF power deposition. Furthermore, the operational aspects of various instruments may be adversely impacted by the electromagnetic fields used for MR imaging.

Artifacts associated with the use of a surgical instrument or device can be particularly problematic if in the imaging area of interest during its intended use. To address these problems, various surgical instruments and devices have been developed that do not present an additional risk or problem to the patient or MRI healthcare practitioner in the interventional MRI environment.

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