Room: Exhibit Hall | Forum 4
Purpose: Hospitals are moving away from ethylene oxide (EtO) gas sterilizers due to safety and regulatory issues. Historically, EtO has been used to sterilize brachytherapy devices that may be sensitive to excessive heat or moisture. Faced with the phasing out of EtO sterilization at our facility, we adapted the materials and designs of specialized patient-specific brachytherapy devices for steam sterilization.
Methods: Dura plaques used for intraoperative irradiation of the spinal dura were made from 0.5mm-thick polymeric films embedded with beta-emitter 32P and bonded to Lucite acrylic or 3D-printed backings, and EtO sterilized inside Lucite shielding containers. Polyetherimide (PEI), an FDA approved material for steam sterilization, was selected as the alternative material for the plaque backings and containers. A container appropriate for steam sterilization was designed with sufficient vents to allow for evaporative drying inside while providing adequate radiation shielding. A dedicated mobile steam sterilization unit was acquired and sterilization protocols developed in concert with personnel from Infection Control and Sterile Processing. A dummy plaque and shielding container were made from PEI to test the materials and protocols, and the temperature inside the container was confirmed with steam sterilizer indicator strips.
Results: The container design was modified until it provided sufficient venting to achieve sterilization and allow for evaporative drying of the plaque after sterilization, while also providing adequate shielding (<2 mR/hr at the vents). The material design and sterilization protocols developed here will be used for future patient-specific brachytherapy applicators.
Conclusion: EtO sterilization is likely to disappear as an option in the future and brachytherapy practitioners should plan for any necessary device modifications. PEI was found to be an appropriate material, available in either sheets or cylindrical rods, and able to be easily machined. With appropriate design modifications, our intraoperative brachytherapy programs will be able to continue under new protocols.
Not Applicable / None Entered.