Classification Closed-loop obstruction Fixation of bowel loop: Coffee bean sign:gas filled loop pseudotumor:fluid-filled loop U-shaped dilated bowel loop Increasing intraluminal fluid Beak sign:point of obstruction -Whirl sign:twisting of bowel Classification Closed-loop obstruction – Fixation of bowel loop: Coffee bean sign: gas filled loop pseudotumor: fluid-filled loop U-shaped dilated bowel loop – Increasing intraluminal fluid – Beak sign: point of obstruction – Whirl sign: twisting of bowel