Low-Dose TOF-PET Based on Surface Direct Conversion of 511 keV Gamma Rays in Kapton Laminar MCPs

We present the design and simulation of a full-body time-of-flight positron emission tomography (TOF-PET) detector based on layered Kapton laminar microchannel plates (LMCPs). The LMCP architecture consists of stacked thin dielectric laminae with micropatterned surfaces forming channels that may be tailored to support secondary electron emission, analogous to conventional MCPs. Using the TOPAS (Geant4-based) toolkit, we simulate a detector composed of twelve concentric cylindrical LMCP layers, each one inch thick. In our model, 511 keV gamma rays undergo Compton scattering in Kapton laminae to generate energetic electrons. For each event, we record the position, energy, and direction of scattered electrons and determine channel entry based on their range in Kapton. Secondary electron amplification within the channels is a critical parameter that will require further study. We present reconstructed images from simulated Derenzo and XCAT-brain phantoms, evaluating high-resolution imaging performance at reduced radiation dose. We evaluate the reconstruction performance by NEMA standards for spatial resolution and sensitivity, including the FWM of the point spread function(PSF) and the contrast to noise ratio(CNR) of the Derenzo phantom image.