Sonographic features related to volvulus in neonatal intestinal malrotation

This 3 year prospective study evaluated the sensitivity and specificity of abdominal ultrasonography and color Doppler ultrasonography in 31 neonates with suspected malrotation or malrotation with volvulus. Water instillation was used to detect duodenal dilatation, edema, and malrotated bowels. Twen ty patients with ultrasonographic characteristics of inversion of the super ior mesenteric artery and superior mesenteric vein were later surgically pr oved to have malrotation. Nine of these 20 patients also had volvulus. Sono graphic features suggestive of volvulus included duodenal dilation with tap ering configuration (8 of 9 cases, 89%), fixed midline bowel (8 of 9 cases, 89%), whirlpool sign (8 of 9 cases, 89%), and dilation of the distal super ior mesenteric vein (5 of 5 cases, 100%). The sensitivity and specificity o f duodenal dilation with tapering configuration for detecting volvulus were 89% and 92%, respectively; of fixed midline bowel, 89% and 92%; of whirlpo ol sign, 89% and 92%; and of dilation of distal superior mesenteric vein, 5 6% and 73%. The results of this study indicate that ultrasonographic featur es of inversion of the superior mesenteric artery and superior mesenteric v ein could aid in the diagnosis of malrotation, and certain sonographic feat ures can also be used to evaluate volvulus, a condition requiring emergent operation.