  The low cost and high resolution gas-based Multi-gap Resistive Plate Chamber
(MRPC) opens a new possibility to find an efficient alternative detector for
Time of Flight (TOF) based Positron Emission Tomography, where the sensitivity
of the system depends largely on the time resolution of the detector. Suitable
converters can be used to increase the efficiency of detection of photons from
annihilation. In this work, we perform a detailed GEANT4 simulation to optimize
the converter thickness thereby improving the efficiency of photon conversion.
Also we have developed a Monte Carlo based simulation of MRPC response thereby
obtaining the intrinsic time resolution of the detector, making it possible to
simulate the final response of MRPC-based systems for PET imaging. The result
of the cosmic ray test of a four-gap Bakelite-based MRPC operating in streamer
mode is discussed.
