Segmentation using Graph cut with contour as input signal

I want to segment a 3D image using a Graph Cuts metodology, but using as an input signal the contour of object in different slices. In this sense, the input could be a curve clicking with mouse on some images.

How could I modify for example the Jing Yuan algorithm's called continuous max-flow to insert this input (<http://www.mathworks.com/matlabcentral/fileexchange/34126-fast-continuous-max-flow-algorithm-to-2d3d-image-segmentation)>?

Thank you very much in advance