Flexible gamma photon detector based on plastic scintillation optical fibers

Abstract

Detecting small-volume tumoral tissues is a central goal within the nuclear imaging disciplines. Early detection of such small tumors may contribute to the suitable treatment of diverse cancers or the identification of metastatic nodules. Furthermore, the application of feasible radionuclides could contribute to the identification of such tumoral tissues. However, characterizing such radiation sources requires detectors that must adapt their forms to obtain a precise identification of the tumor location. This study's primary outcome was a suitable flexible gamma-ray detector capable of measuring the radiation emitted from small-volumetrics. The detector implements scintillating plastic fibers integrated into an avalanche photodiode (APD), which constitute the main elements of the proposed detection system. The proposed system was characterized in terms of the electrical response, as well as the detection characteristics of the radionuclide source. The optical efficiency of the plastic optical fibers and the photons detection settings of the APD served to develop a prototype of a gamma-probe system. This detection device can be specifically oriented to provide a trustable gamma detector of small-volume radiation sources with the corresponding corrections for the scattering and the compensation for attenuation and background factors. The system design included the corresponding electrical conditioning circuit and the signal processing software. This software detected and discriminated the voltage level to characterize the photon energy. A preclinical study represented the distance and angular sensibilities of the proposed detector to the 99m Tc-RGD (pegylated arginine-glycine-aspartic acid) radiopharmaceutical in a murine model.