1. A method for determining an optical absorption coefficient of a volume of interest (VOI) in a turbid medium using time resolved optical modalities said method comprising: injecting light in said medium at an injection point; detecting light exiting said medium at a detection point; generating a Temporal Point Spread Function (TPSF) using said detected light; correlating a predetermined time point or time gate of said TPSF with said VOI wherein said VOI comprises equiprobable effective photon paths; and determining said optical absorption coefficient within said VOI using one or more characteristics of said TPSF.