| PurposeThe retrospective clinical trial aims to:(1) to investigate and compare the value of unenhanced CT and enhanced CT in diagnosing intestinal obstruction. (2) to evaluate the value of multi-planar reformat (MPR) and axial images in diagnosis of intestinal obstruction. (3) to analyze the characteristic features for predicting intestinal strangulation on CT.Materials and MethodsFrom December 2006 to December 2010 in Tianjin Medical University General Hospital,195 cases with intestinal obstruction proved by operations or endoscopy or discharge of Intestinal stone were included by searching the hospitalization records and CT examination record. Review by the Hospital Ethics Committee, this retrospective study exempt from informed consent. The data were divided into noenhanced CT group vs enhanced CT group by means of CT examination. There were 40 CT images data sets which had post-processed by MPR, these data were divided into CT axial images group and MPR images group. All 195 cases were divided into simple intestinal obstruction and complex intestinal obstruction according to the surgical and pathological results. Two experienced abdominal radiologists randomly and blindly inspected the CT findings and consensuses were accomplished by discussion. Observation criteria included:(1) to determine whether there was intestinal obstruction, (2) to assess the severity of intestinal obstruction, (3) to identified the site of obstruction, (4) to distinguish between simple and closed loop /strangulated intestinal obstruction, (5) to determine the cause of obstruction. These analysis results were statistically compared with the surgical pathological feindings: (1) to compare diagnostic accuracy of bowel obstruction between the unenhanced CT and enhanced CT. (2) to compare the diagnostic accuracy of intestinal obstruction between the CT axial images and MPR images, and to assess the differences of diagnostic confidence in identification of obstructive site. (3) to assess the characteristic sign for predicting strangulated intestinal obstruction CT signs. Means of statistical analysis included:(1) and (2) were analyzed usingχ2 test and (2) the differences of diagnostic confidence in identification of obstructive site were analyzed using paired t test, (3) using logistic regression analysis.ResultsThe unenhanced CT and the enhanced CT were 144 cases and 51 cases respectively As for identifying whether there was obstruction and the degree of obstruction, the diagnostic accuracy were both 100%. And the diagnostic accuracy of recognition site of obstruction was 75.7% and 80.4% respectively, there was no statistically significant difference between them (P=0.557). The diagnostic accuracy of identification between simple and closed loop/strangulated intestinal obstruction by enhanced CT (96.1%) was better than of unenhanced CT (86.8%), but the difference was not statistically significant (P=0.066). The diagnostic accuracy of enhanced CT (84.3%) for identifying the cause of intestinal obstruction was better than unenhanced CT (69.4%), the difference was statistically significant (P=0.039). The CT diagnostic results of 40 cases with MPR images were compared with corresponding axial images. The diagnostic results for the presence of intestinal obstruction and the severity of obstruction was both 100%. As to determine the location of the bowel transition, the diagnostic results were identical (85% for both), however, MPR images could significantly improve diagnostic confidence (P==0.033) The diagnostic results for closed loop/strangulated intestinal obstruction were both 75%. The diagnostic accuracy of the cause of intestinal obstruction by MPR images and axial images were 87.5% and 85.0% respectively, the difference was not statistically significant (P=0.745). There were four characteristic signs for predicting intestinal strangulation, of which the correlation were statistically significant by Logistic regression analysis. They were mesenteric standing(P=0.001), ascites (P=0.003), increased attenuation of the intestinal wall (P=0.008) and beak sign (P=0.042).ConclusionThe diagnostic accuracy of the cause of intestinal obstruction by unenhance CT was relatively lower than that of enhanced CT, however, there was no statistically significant difference in diagnostic accuracy for identifying the severity of intestinal obstruction, determining the site of obstruction, distinguishing simple and closed loop /strangulated intestinal obstruction, which is suggesting that unenhanced CT is an effective method for diagnosis of intestinal obstruction as well. MPR images could be more intuitive for displaying the transition zone of intestinal obstruction. However, MPR has no diagnostic advantages in identifying the severity of obstruction, distinguishing simple and closed loop/strangulated intestinal obstruction, determining the cause of intestinal obstruction. There were four specific CT sign for predicting intestinal strangulation, they are mesenteric standing, ascites, increased attenuation of the intestinal wall and beak sign. |
PDF Full Text Request