Radiation Testing of the GERD Stimulation Therapy System Using a Particle Accelerator

Area of Science:

• Medical Devices
• Radiation Oncology
• Biomedical Engineering

Background:

• Particle accelerators are used in cancer treatment.
• Neurostimulators like EndoStim are implanted to treat conditions such as gastroesophageal reflux disease.
• The potential impact of radiation exposure on implanted medical devices requires investigation.

Purpose of the Study:

• To evaluate the performance of EndoStim neurostimulators under radiation exposure.
• To determine if radiation from a particle accelerator affects EndoStim device function.
• To assess the safety of using EndoStim during radiation therapy.

Main Methods:

• Twelve EndoStim Lower Esophageal Sphincter (LES) Stimulation System neurostimulators (six EndoStim I, six EndoStim II) were tested.
• Devices were programmed for passive and active stimulation modes.
• Exposure to 18 MV Bremsstrahlung X-rays at 6 Gy/min up to a cumulative dose of 80 Gy was administered.

Main Results:

• Device performance parameters including stimulation frequency, amplitude, pulse width, and voltage were monitored.
• No significant changes in device operation or parameter magnitudes were observed.
• All functional parameter changes remained within ±10% of baseline values.

Conclusions:

• EndoStim I and II implantable pulse generators are resistant to X-ray radiation up to 18 MV.
• The devices demonstrated immunity to radiation at dose rates up to 6 Gy/min and cumulative doses of at least 80 Gy.
• EndoStim LES Stimulation System neurostimulators can withstand direct radiation exposure, supporting their use in patients undergoing radiation therapy.