how to select small dark part of an gray image ?

I am written an application that select cells in the liver carcinogens, and I'm having trouble identifying small parts infected with cancer Is there a algorithm to do so. Note that the picture is image scan of the liver.

this problem is like a problem that disused in Recorded Webinars(Automating the Analysis of Life-Sciences Data with MATLAB) but in gray.

[Walter Roberson]

http://www.mathworks.com/matlabcentral/answers/7924-where-can-i-upload-images-and-files-for-use-on-matlab-answers

Answer 1

[Image Analyst]

Since their Cancer Detection Toolbox hasn't been released yet, you might browse here: http://iris.usc.edu/Vision-Notes/bibliography/contentsmedical.html#Medical%20Applications,%20CAT,%20MRI,%20Ultrasound,%20Heart%20Models,%20Brain%20Models

[Isee You]

Recorded Webinars(Automating the Analysis of Life-Sciences Data with MATLAB)

is their any way to apply that in gray image

[Image Analyst]

Probably, but I have not seen that webinar.

[Isee You]

Thank you for your answer.