Adhesive small-bowel obstruction: value of CT in identifying findings associated with the effectiveness of nonsurgical treatment.

Purpose: To identify computed tomographic (CT) findings that are associated with the effectiveness of nonsurgical treatment in patients with adhesive small-bowel obstruction ( SBO small-bowel obstruction ) that was initially treated medically.
Materials and Methods: The local institutional review board approved this retrospective study; the informed consent requirement was waived. Multi-detector row CT studies in 159 patients (64 women, 95 men; median age, 69 years) with adhesive SBO small-bowel obstruction that was initially treated medically were reviewed retrospectively and independently by two emergency radiologists to identify numerous CT findings that could be associated with the effectiveness of nonsurgical treatment. Results were compared according to the success or failure of nonsurgical treatment. Univariate statistical analyses were performed for qualitative and quantitative data, as appropriate, and each significant parameter was entered in a multivariate logistic regression analysis. The κ statistic and correlation coefficients were used to assess interobserver agreement, as appropriate.
Results: Nonsurgical treatment succeeded in 113 patients (71%) and failed in 46 patients (29%). At univariate analysis, an anterior parietal adhesion, a feces sign, and the lack of a beak sign were associated with successful nonsurgical treatment, whereas two beak signs or more, a whirl sign, a C- or U-shaped appearance of the bowel loop, and a high degree of obstruction were associated with nonsurgical treatment failure. At multivariate analysis, fewer than two beak signs and the presence of an anterior parietal adhesion were independent predictors of the effectiveness of nonsurgical treatment, with odds ratios of 0.27 and 0.11, respectively.
Conclusion: The number of beak signs and the location of the transition zone in relation to the anterior peritoneal layer are independent signs associated with the success or failure of nonsurgical treatment.