Prior image based three dimensional imaging

Described herein are technologies for facilitating three-dimensional imaging based on prior image data. In accordance with one aspect, deformable registration is performed to align three-dimensional (3D) image data to a sparse set of two-dimensional (2D) projection image data of at least one structure of interest. An iterative reconstruction scheme may then be performed to minimize a difference between the aligned 3D image data and the 2D image data.