collar button lesion

Any of a number of small deep ulcers with narrow necks, which parallel a barium-filled large intestinal lumen affected by ulcerative colitis; the ‘button’ surface corresponds to an eroded ulcer base, and the ‘button neck’ corresponds to the sides of the islands of preserved mucosa; a similar phenomenon occurs in colonic amebiasis ulcers

collar button lesion

GI disease Any of a number of small deep ulcers with narrow necks, which parallel a barium-filled large intestinal lumen, affected by ulcerative colitis; the 'button' surface corresponds to an eroded ulcer base, and the 'button neck' corresponds to the sides of the islands of preserved mucosa; a similar phenomenon occurs in colonic amebiasis ulcers. See Flask lesion.