MATLAB: Left ventricle segmentation

Question

hello…can you please help me….

I'm working on a dicom image and i wanna extract the LV (left ventricular wall) so here is the steps i used after some work on that image : 1-edge detection using canny method

2-then 'dilate' the result edge image

3-'close' to fill the holes with "disk " structuring element

4-then 'dilate' after close

5-find the 'complement' (negative) of the dilated image

6-clear borders by 'imclearborder'…..

NOW, after all of that i've an image that contains a nearly circular two concentric circles that represent the left ventricular wall and other organs such as liver, they are all in white with a black background as shown in that link http://i1131.photobucket.com/albums/m541/Lomie55/LV_wall_image_mask.jpg all i want is that the final image only contain the LV white wall with a black background in other words a mask for the LV wall…can you please help me to know how to extract these two concentric circular part as you can see in the figure (link) above…anymore questions??…thanks in advance…

Answer 1

Looking at your original image, I don't know if it was necessary or useful to go through all those steps. I get the impression from the image that if you were to threshold at a sufficiently high grey level, and then imlabel() and regionprops(), that the target area would be the one with the lowest eccentricity.