[vtkusers] head model from MRI

[John Hunter]

I have some MRI data (sequential series of 2d slices) from which I
want to build a 3D head model.  I imagine that one way to do this is to
take each slice and identify a closed boundary based on some
thresholding function which would be the silhouette for that slice and
then reconstructing the 3d model from the silhouettes.  There would
have to be some continuity constraints on the silhouettes between
slices, and so this probably turns out to be an optimization problem.

Since I suspect this is a fairly common problem, I am hoping someone
can point me to some existing code or literature to speed me along.

Thanks,
John Hunter