A funny patch in colitis

This is the colon of a patient with long-standing colitis and PSC on annual surveillance. These were found after indigo carmine dye spray.
WHAT IS YOUR ENDOSCOPIC DIAGNOSIS?
a) patches of crypt distortion
b) serrated lesions
c) a flat adenomas

Explanation

Actually, these are patches of 'crypt distortion'.   Often seen after pan-colonic dye spray and VERY difficult to distinguish from serrated lesions.  The crypt openings are a little larger than normal and strangely these seem to develop in patches which can be very large.  In a case like this, I would take samples to reassure and alert subsequent surveillance colonoscopists to the presence of these odd lesions.  In my experience they are usually seen in long standing colitis which has been troublesome in the past and I wouldn't be entirely surprised if future research find that these are more commonly found in patients who go on and develop flat dysplasia in the future.   Below is a close-up of a lesion.