Objective To investigate the imaging features of intestinal volvulus on multi-detector row spiral CT (MDCT). MethodsThirty-one patients with surgically confirmed intestinal volvulus were included in this study. Nine patients received MDCT plain scan, 22 received contrast enhanced MDCT scan and 5 of them had additional CT angiography. Two abdominal radiologists analyzed the MDCT imaging features of intestinal volvulus observed, such as the location, direction of rotation, degree of volvulus, appearance rate of the “whirl sign” and the “beak sign”, bowel wall thickening and ascites and the possible causes of volvulus, which were recorded with review of surgical findings. Results The location of volvulus included duodenum (1 case), jejunum (23 cases), ileum (3 cases), entire small intestine (2 cases) and sigmoid colon (2 cases). The location of volvulus was correctly diagnosed based on MDCT findings in 27 patients (27/31; 87.0%). The direction of volvulus was correctly diagnosed for all patients based on MDCT findings (clockwise in 11 cases and counterclockwise in 20 cases). The degrees of volvulus assessed on MDCT findings were respectively 180° in 13 cases, 360° in 12 cases, 540° in 2 cases, 720° in 2 cases and 900° in 2 cases, as compared with surgical findings of 180° in 17 cases, 360° in 10 cases, 540° in 1 case, and 720° in 3 cases. The diagnostic accuracy of MDCT for assessing the degree of volvulus was 74.2%. The “whirl sign” and “beak sign” appeared in 18 and 20 patients, respectively. Bowel wall thickening and ascites were showed in 9 patients. In 5 patients with reconstructed images, the images obtained by maximum intensity projection (MIP) and volume rendering (VR) techniques showed the abnormality of mesenteric vessels in all patients, and the multi-planar reconstruction (MPR) image of one patient showed the “whirl sign” and the “beak sign”. The causes of intestinal volvulus were identified on MDCT in 10 patients. Conclusion The “whirl sign” and the “beak sign” are the characteristic images of intestinal volvulus on MDCT. Bowel wall thickening and ascites may indicate the hemody-namic images impairment of volvulus. MDCT plays valuable role in the diagnosis of intestinal volvulus.
【Abstract】 Objective Using 16-slice multi-detector row helical CT (16-slice MDCT) to investigate the value of multiplanar reformation technique (MPR) in the diagnosis of bowel obstruction. Methods Thirty patients with surgically (27 cases) or clinically (3 cases) proofed diagnosis of bowel obstruction underwent 16-slice MDCT examination of the entire abdomen. All cases had plain CT scan, while 20 cases had additional contrast-enhanced CT scan at portal venous phase. In addition to the conventional axial images, the original CT raw data were then reconstructed into both coronal and sagittal images using MPR technique. Imaging findings were analyzed on axial, MPR coronal and sagittal images. Results Among the 30 patients with bowel obstruction, there were 8 cases caused by adhesion, 7 by simple intestinal tumor, 5 by intussusception (including caused by instestinal tumor), 4 by abdominal hernia, 2 by volvulus, 1 by ileocecal abscess, 1 by stenosis of mesenteric artery，1 by retroperitoneal cyst, and 1 by carcinoma in pancreatic tail. Six patients developed intestinal ischemia or strangulation. Both axial and MPR images correctly depicted the presence of bowel obstruction. Based on CT axial view （AV）, the site and the underlying etiology of bowel obstruction were determined in 26 (86.7%) and 22 (73.3%) patients respectively, while the combination with MPR coronal and sagittal images improved the diagnostic performance to 29 (96.7%) and 27 (90.0%) patients respectively. Both axial and MPR images correctly revealed the presence of intestinal ischemia or strangulation in 5 （83.3%）patients. Conclusion MPR technique of MDCT is very useful for evaluating the site and etiology of bowel obstruction, as well as the circulation status of involved bowel loop.