Purpose: To improve safety around MRI simulators and MRI-LINACs using an in-house developed Real-time Location System.
Methods: A Real-Time Location System (RTLS) was developed using Bluetooth Low Energy (BLE) technology. A grid of Bluetooth Low Energy (BLE) sensors was installed throughout the radiation oncology treatment facility at University of Texas Southwestern Medical Center (UTSW), and an artificial intelligence (AI)-based localization engine was developed that enabled us to locate staff, patients, and devices within the facility at a high accuracy (99.99%). Based on the RTLS infrastructure, a suite of applications was developed to locate, verify and time tagged subjects. At each machine console, an iPad installed with the electronic checklist application, called RO-Lifeguard, helps the care team to locate and verify patients and patient-specific accessories prior to treatment. To increase the safety of our MRI simulator and MRI-LINACs, a warning system was implemented in RO-Lifeguard to alert the care team when a tagged MR-unsafe device approaches MR Zone 3. The warning can be issued by audible alarm and/or by a warning message on the RO-Lifeguard screen.
Results: The whole radiation therapy facility was divided into 450 zones, each of which is given an MR safety level. Each tagged subject (person and/or device) is also assigned an MR safety status. The RTLS engine was able to identify subjects' location with high accuracy in treatment areas. When the MR safety policy logic is activated in the RTLS system, the entire facility is under MR safety surveillance in real-time.
Conclusion: MRI simulators and MR-LINACs are powerful tools that improve tissue delineation and offer a great solution to adaptive radiation therapy for moving targets, but they also require an increased commitment to safety practices. Our RTLS-based MR safety surveillance system provides an extra layer of protection in areas where MRI simulators and MR-LINACs are present.
Magnetic Fields, Software, Radiation Protection