We calculate the time-resolved flux of photons transmitted across an o
ptically turbid slab containing a partially absorbing inclusion. An an
alytical expression is obtained for the flux at a detector positioned
opposite a point source (at a distance equal to the thickness of the s
lab) when the center of the inclusion lies on the line connecting thos
e points. The calculation employs a discrete-time lattice random-walk
model of photon transport. The resulting expression is used to assess
the affects of time resolution on the detectability of the inclusion.