“…Implicit models using level sets have gained increased interest for cell segmentation since topological changes can be handled naturally (e.g., Ortiz de Solorzano et al, 2001;Dufour et al, 2005;Nath et al, 2006;Chang et al, 2007;Palaniappan et al, 2007;Yan et al, 2008;Maška et al, 2009;Mosaliganti et al, 2009;Padfield et al, 2009;Ersoy et al, 2009;Dzyubachyk et al, 2010;Xu et al, 2011). Ortiz de Solorzano et al (2001) developed a two-step level set approach for segmenting cells, which employs a gradient-based energy functional.…”