How can I remove background from cephalometric x-ray image using matlab?

I want to remove background of cephalometric x-ray image and i want to detect landmarks in the edges of the image. How can i first remove background and extract cephalogram from the image? I want to how to detect landmark points in the edges of the image also.

[Image Analyst]

You could use image processing. What else can I say?

http://www.mathworks.com/matlabcentral/answers/6200-tutorial-how-to-ask-a-question-on-answers-and-get-a-fast-answer