Whirl sign in small bowel volvulus.

DESCRIPTION A 43-year-old man without previous abdominal operations came to the hospital due to sudden onset abdominal pain and vomiting. His abdomen was soft. Laboratory data confirmed leukocytosis and severe acidosis (pH 7.16). Abdominal CT revealed a twist of mesentery around the axis of the superior mesenteric artery (figure 1) and poor contrast-enhanced bowel loops (figure 2). Emergent laparotomy showed that the small bowel volvulus had caused bowel necrosis. No malrotation or adhesions were seen. A segmental bowel resection was performed; the patient recovered and was discharged on postoperative day 16. Small bowel volvulus has been responsible for 1.7% of all intestinal obstructions and is classified into two types. The primary type occurs in an otherwise normal abdominal cavity and is rare in adults, accounting for 10–22% of small bowel volvulus in Western countries, and 30% in Africa and the Middle East. The secondary type occurs in the presence of a pre-existing lesion, such as an adhesive band or malrotation.