18. The system of claim 13 , wherein the geometric fitting includes utilizing an adaptive gradient ascent technique with automatic step-size selection that is convergent to a mode of a kernel-smoothed estimate of a Gaussian function surface.
13. A system for identifying a structure of interest within image data, comprising: an image receiving unit for receiving image data; a first graphical user interface for displaying the received image data and soliciting an initial point within the received image data from a user; an image processing unit for transforming the received image data into a scale-space for performing geometric fitting using prior-constrained mean shift on the scale-space image data to identify a structure candidate in a vicinity of the initial point and for setting up a prior constraint for subsequent iterations; and a second graphical user interface for presenting the identified structure candidate to a user and querying the user to determine whether the identified structure candidate is a structure of interest, wherein when the identified structure candidate is determined to not be a structure of interest, performing geometric fitting using prior-constrained mean shift and presenting an identified structure candidate are repeated until it is determined that an identified structure candidate is a structure of interest.