1. A method for differentiating pulmonary nodules in digitized medical images comprising the steps of: identifying an object of interest from a digital image of the lungs; computing a first distance map of each point of said object of interest; determining a seed point from said first distance map; starting from said seed point, growing a first region by adding successive adjacent layers of points until a background point is reached; and partitioning said first region into a nodule region and a non-nodule region.