1. An automated method for use in obtaining a boundary of a structure within a medical image, comprising: obtaining a 2-D image including a structure of interest; identifying a center point of said structure wherein identifying said center point of said structure comprises: extending a plurality of parallel lines through said 2-D image; calculating an energy value along each said parallel line; based on said energy values, identifying approximate edges of said structure in said parallel lines that pass through said structure; extending a plurality of radial lines from said center point; identifying energy values along each said radial line; based on said energy values, identifying a boundary of said structure of interest.