 Immediately after pCLE evaluation, and before proceeding to the next colon segment, targeted biopsies will be taken from the mucosal area evaluated. Bleeding can impair image quality, therefore probe will be placed gently in contact with the tissue in order to avoid trauma and pCLE imaging will be completed in a region before mucosa biopsy. The endoscopist performing the pCLE will be blinded to the status of the patient and the images will be later analyzed in detail blindly by two different persons with more than two years experience in endomicroscopy. 