Graph cut lung segmentation algorithm & matlab codes

I am in need to get lung boundary with lung edge only not including ribs & cavical bones, later this is taken as a input to find tuberculosis affected area in the lung region & then mark the particular TB affected area in the original chest x-ray

Answer 1

[Image Analyst]

See this http://www.mathworks.com/matlabcentral/answers/106252-how-can-i-segment-lung-fiels-in-x-ray-images#comment_180338

and this: http://www.mathworks.com/matlabcentral/answers/154027#comment_236068, especially my first comment that is hidden.