“…TRUS images are cross-sectional slice images, obtained at fixed intervals from the prostate. Due to a very low signal-to-noise ratio, traditional edge detectors fail to extract the correct boundaries (Insana & Brown, 1993;Nanayakkara, Samarabandu, & Fenster, 2006). Consequently, many methods have been introduced to facilitate more accurate automatic or semiautomatic segmentation of the prostate boundaries in these images (Betrounia, Vermandela, Pasquierc, Maoucheb, & Rousseaua, 2005;Chiu, Freeman, Salama, & Fenster, 2004;Gong, Pathak, Haynor, Cho, & Kim, 2004;Ladak et al, 2000;Pathak, Chalana, Haynor, & Kim, 2000;Prater & Richard, 1992;Noble & Boukerroui, 2006;Shen, Zhan, & Davatzikos, 2003;Wang, Cardinal, Downey, & Fenster, 2003).…”