Development of a silver-doped zinc sulfide incorporated wearable fabric for proton beam surface imaging

In radiation therapy, a major challenge is the lack of visualization of radiation beams as they target patients. To address this, we developed a wearable fabric incorporating silver-doped zinc sulfide (ZnS(Ag)) scintillator powder, designed for real-time monitoring of beams on the curved surfaces of patients during proton therapy.

The ZnS(Ag)-incorporated wearable fabric was created by mixing ZnS(Ag) with a two-part silicone adhesive, applying this mixture to a cotton fabric, and allowing it to solidify. This process produced a scintillating fabric capable of high-intensity imaging of surface proton beams when worn by a patient. To assess its performance, we also fabricated a flexible ZnS(Ag) sheet by applying the mixture onto a plastic plate for solidification, which was then peeled off.

Using the ZnS(Ag)-incorporated wearable fabric in combination with a cooled CMOS camera, we successfully imaged scintillating areas during proton beam irradiation under dark conditions in the therapy room. The fabric also effectively revealed scintillating areas when placed on a black mannequin. While the relative detection efficiency of the developed ZnS(Ag)-incorporated flexible scintillator sheet was one-third that of the ZnS(Ag) plate or a plastic scintillator for alpha particles, its light output was 1.9 times higher than that of the plastic scintillator.

The ZnS(Ag)-incorporated wearable fabric's flexibility makes it particularly suitable for surface beam imaging in proton therapy, suggesting promising potential for this technology in therapeutic imaging applications.