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What is Which of the following is the earliest sign of ulcerative colitis on double-contrast barium enema study - and explain in detail?
Earliest radiological change of UC on barium enema is blurring of the mucosal lining and a fine granularity when mucosa is seen enface due to edema.
Earliest radiological change of Crohn's disease → Aphthous lesions (Bull's eye or Target lesions).