Design for a depth of interaction detector for small animal PET using multiple quasi-block scintillators

We designed a detector for small animal positron emission tomography to achieve high resolution and sensitivity. By using a quasi-block scintillator, superior sensitivity was achieved compared to existing scintillation pixels. The scintillator was arranged in several layers to measure the location where gamma-ray interaction occurred. DETECT2000 simulation was performed to evaluate the performance of the designed detector. DETECT2000 is capable of simulating the movement, scattering, reflection, and absorption of light generated within a scintillator. Using these parameters, a quasi-block scintillation detector was designed, and light emitted by gamma-ray interaction was generated throughout the scintillator. Light generated by gamma-ray events in the entire area was acquired at 1 mm intervals as a light signal from optical sensors placed on the sides of four quasi-block scintillators, and a flood image was obtained using the light signal. As a result, images were confirmed to be separated without overlap in all areas except for the positions of gamma ray events generated at the corners and edge of the quasi-block scintillator. It is expected that the system spatial resolution of around 1 mm can be achieved by imaging the locations of all gamma-ray events occurring at 1 mm intervals.