This investigation is described by Dana Mackenzie in
"Topologists Take Scalpel to Brain Scans,"
SIAM News, Vol 37, No 7, Sep 2004.
[2] L. Abrams, D.E. Fishkind and C.E. Priebe, "A proof of the spherical homeomorphism conjecture for surfaces," IEEE Transactions on Medical Imaging, Volume 21, Number 12, pp. 1564-1566, December 2002. (access via IEEE Xplore)
[3] L. Abrams, D.E. Fishkind and C.E. Priebe, "The generalized spherical homeomorphism theorem for digital images," IEEE Transactions on Medical Imaging, Volume 23, Number 5, pp. 655-657, May 2004. (access via IEEE Xplore)
[4] L. Abrams and D.E. Fishkind, "A genus bound for digital image boundaries," SIAM J. Disc. Math., to appear. preprint