  The TT-PET collaboration is developing an MRI-compatible small animal PET
scanner in which the sensitive element is a monolithic silicon pixel ASIC
targeting 30 ps RMS time resolution. The photon-detection technique is based on
a stack of alternating layers of high-Z photon converter and 100 $\mathrm{\mu
m}$ silicon sensors, to produce a scanner with 0.5 $\mathrm{\times}$ 0.5
$\mathrm{\times}$ 0.2 $\mathrm{mm^{3}}$ granularity for precise
depth-of-interaction measurement. In this paper we present the results of
simulation studies for the expected data rate, time-of-flight and spatial
resolution, as well as the performance of image reconstruction with and without
the use of timing information.
