Here are medical imaging datasets I am aware of: Neuroimaging (see http://www.nitrc.org for others) OASIS http://www.oasis-brains.org/ ADNI http://adni.loni.ucla.edu/ (huge dataset, requires application) OpenfMRI http://openfmri.org/ EEG http://eeg.pl/epi

Some other applications, example CT Colonography http://www.acrin.org/