PT - JOURNAL ARTICLE AU - Xin Li AU - Lars Furenlid TI - An analysis of side readouts of monolithic scintillation crystals DP - 2016 May 01 TA - Journal of Nuclear Medicine PG - 1950--1950 VI - 57 IP - supplement 2 4099 - http://jnm.snmjournals.org/content/57/supplement_2/1950.short 4100 - http://jnm.snmjournals.org/content/57/supplement_2/1950.full SO - J Nucl Med2016 May 01; 57 AB - 1950Objectives We have analyzed the potential spatial and energy resolution of side readouts of monolithic scintillator crystals.Methods Monolithic scintillation crystals are conventionally read out with an array of photomultipliers arranged on the crystal face. We consider an alternative arrangement where the photon sensors are attached on the 4 edges of the scintillation crystal. We have performed Monte-Carlo simulations to trace scintillation-photon transport inside the detector crystal and find that when there is air or another low-index of refraction material at the faces, most of the scintillation light is transported to the side surfaces by total internal reflection (TIR). The Mean Detector Response Function (MDRF) was generated by performing transport simulations originating at a regular grid of gamma-ray interaction locations. We can simulate an event by sampling from the MDRFs and applying Poisson noise, and then estimate the interaction position and deposited energy by maximum likelihood (ML) estimation. By finding the light distribution on the scintillation crystal sides as a function of gamma-ray interaction location, and the crystal's side length/thickness ratio, index of refraction, light yield and transparency, we can optimize the arrangement of light sensors along the edges by analyzing each configuration's Fisher informationResults Our preliminary results suggest that it is feasible to recover position and energy estimates with this detector geometry. We find that the spatial resolution varies across the detector area, with the lowest resolution at the center of the scintillation crystal. The spatial resolution (FWHM) is proportional to the side length of the scintillation crystal. The spatial resolution close to the sides are very sensitive to the number, size, and location of the photon sensors. With a scintillation crystal with a refractive index of 1.82, the total number of scintillation photons transported to the detector sides is 83.7% and independent of crystal thickness.Conclusions The feasibility of this novel side-readout detector is considered. The detector design can be optimized to reduce the total number of photon sensors without greatly affecting its spatial resolution. The high percentage of scintillation photons transported to the side surfaces indicates that energy resolution may be better than can be achieved with conventional modular cameras. $$graphic_B91D7A9B-6D7E-4DF7-A469-84CCCD4F1ECA$$