Midgut volvulus in an adult.

We report a case of duodenal malrotation that presented in adulthood as midgut volvulus. On colour Doppler ultrasound, findings of a clockwise rotation of the superior mesenteric vein around the superior mesenteric artery (whirlpool sign) and a distinctive 'whirl'-like pattern resulting from an encircling of loops of the bowel around the SMA on CT is diagnostic of midgut volvulus.