Jinghao Zhou Sukmoon Chang Dimitris N. Metaxas Leon Axel Vessel boundary extraction using ridge scan-conversion deformable model. 189-192 2006 conf/isbi/2006 ISBI http://dx.doi.org/10.1109/ISBI.2006.1624884 db/conf/isbi/isbi2006.html#ZhouCMA06