eng Oriental Scientific Publishing Company Biomedical and Pharmacology Journal 0974-6242 2020-09-25 13 3 1357 1365 10.13005/bpj/2005 34730 article G. Vaira Suganthi 1 J. Sutha 2 M.Parvathy 1 C.Durga Devi 3 Sethu Institute of Technology, Virudhunagar District, India AAA College of Engineering and Technology, Virudhunagar District, India Madurai Medical College, Madurai, India Pectoral Muscle Segmentation is an essential pre-processing technique used for subsequent processing of finding abnormalities in mammograms. The aim of this paper is to segment pectoral muscle region from the Mediolateral Oblique view of mammograms. The proposed algorithm uses the active contour and intensity based thresholding approach to identify the boundary existing between the pectoral muscle region and the rest of the breast area. The algorithm works in two stage; Contrast enhancement and contour identification in the pre-processing stage and thresholding approach in the second stage. The algorithm is experimented with the 322 mammogram images available in the Mammographic Image Analysis Society (MIAS) database. The proposed algorithm successfully segmented 298 images and thus produced an accuracy of 92.55%. The algorithm is compared with the existing methodologies and shown promising results. https://biomedpharmajournal.org/vol13no3/pectoral-muscle-segmentation-in-mammograms/ Contour Intensity Mammograms Pectoral Muscle Pre-processing Thresholding