Room: ePoster Forums
Purpose: To present a MRI safety workflow for radiation therapy (RT) patients with a cardiovascular implantable electronic device (CIED). CIEDs constitute a significant challenge for RT given reduced institutional experience with MRI safety issues compared with radiology. CIED patients may undergo multiple fractions or long adaptive procedures. In addition, MR Conditional implantable pulse generators including CIEDs are typically off-label for low field MRI-guided radiation therapy (MR-IGRT).
Methods: An MRI safety program was developed for RT in accordance with ACR requirements. MRI safety screening policies, procedures, and workflows from radiology were adapted to the RT clinical workflow. Waivers were approved for off-label use of CIEDs. Time outs with relevant personnel were performed before the CIED was reprogrammed and the patient was brought into the MRI suite. Patients were continuously monitored using a pulse oximeter by an advanced cardiac life support (ACLS) nurse. High risk patients (e.g., device dependent or device is unsafe for MRI) were excluded due to the lack of advanced monitoring equipment and personnel training. However, these conditions may change due to interest in performing MRI-guided noninvasive stereotactic cardiac radiosurgery for tachycardia patients.
Results: Since October 2017, we performed 1.5 T MRI simulations on two CIED patients, and 0.35 T MR-IGRT simulations and five-fraction treatments on four CIED patients. None of the patients were device dependent. All of the CIEDs and leads were MR Conditional. No adverse events occurred. We have rejected about ten patients who are either device dependent or have an MR Unsafe device. By contrast, Radiology has more MRI safety experience, access to Cardiology resources, advanced monitoring equipment, and closer proximity to the emergency department.
Conclusion: MRI safety in RT has distinct challenges compared to radiology. Multiple or long MRI exams can lead to increased risk to the patient versus a diagnostic MRI exam.