The Impact of High Energy Proton Radiation on Intrathecal Infusion Pumps

Kurzfassung

Background: Exposure to radiation environments such as in radiation therapy, is associated with malfunctions in active implanted medical devices. These errors are most likely caused by single subatomic particles hitting the device memory and altering information. However, there is little information on the response of intrathecal infusion pumps to particle radiation. Methods: 8 explanted and fully functioning intrathecal infusion pumps were irradiated with a radiation therapy proton beam with an energy of 150 MeV and a total particle fluence of 1.1 ∙ 109 protons/cm². One device was irradiated twice. The pumps were read out before and after irradiation and all changes in the programmed parameters were documented. Results: In the post-radiation analysis, devices were found in safety mode and set to a minimum flow rate in 6 cases. This was mostly caused by resets of the devices due to memory errors. Subsequently, all but one pump could not be easily reprogrammed to pre-irradiation settings. Conclusion: The analysis shows a distinct sensitivity of intrathecal infusion pumps to high energy proton radiation. This provides important information for the possible exposure of the devices in proton radiation therapy. However, further research is required to quantify the probability of malfunction.