However, studies testing the use of abdominal radiographs have yielded disparate results [4,5,18,69]. Although some investigators have reported an 80% to 90% success rate in diagnosing SBO using radiographs [5], an overall accuracy somewhat approaching that of CT [7], others have achieved rates only in the 30% to 70% range [4,7,18]. In other studies, abdominal radiographs proved to be of little or no help in assessing the site or cause of SBO [70,71] and were even misleading in 20% to 40% of patients [18]. A relatively recent study; however, found that abdominal radiographs were accurate for detecting acute SBO. It should be stressed; however, that it may be difficult to differentiate an SBO from a postoperative ileus in the perioperative period based on a single examination. Serial examinations showing persistent dilated small-bowel loops with air-fluid levels and relative or complete paucity of gas in the colon favor SBO. Suspected Small-Bowel Obstruction Despite the relatively high accuracy of abdominal radiographs in detecting SBO, CT provides much more information, including the site and cause of the obstruction and complications of SBO. As a result, CT findings generally influence patient management much more than do abdominal radiographs. In light of these inconsistent results, it is reasonable to expect that abdominal radiographs will not be definitive in many patients with a suspected SBO. Radiographs could prolong the evaluation period. Therefore, in patients with a known or suspected SBO, fluoroscopic-contrast examinations (SBFT, conventional enteroclysis), and particularly, cross-sectional imaging examinations (CT, MRI, ultrasound [US]), as well as specialized cross-sectional imaging examinations (CT enterography, CT enteroclysis, MR enterography, and MR enteroclysis), may be more useful options for diagnosis. Variant 2: Suspected intermittent or low-grade small-bowel obstruction. Indolent presentation.
Suspected Small Bowel Obstruction. However, studies testing the use of abdominal radiographs have yielded disparate results [4,5,18,69]. Although some investigators have reported an 80% to 90% success rate in diagnosing SBO using radiographs [5], an overall accuracy somewhat approaching that of CT [7], others have achieved rates only in the 30% to 70% range [4,7,18]. In other studies, abdominal radiographs proved to be of little or no help in assessing the site or cause of SBO [70,71] and were even misleading in 20% to 40% of patients [18]. A relatively recent study; however, found that abdominal radiographs were accurate for detecting acute SBO. It should be stressed; however, that it may be difficult to differentiate an SBO from a postoperative ileus in the perioperative period based on a single examination. Serial examinations showing persistent dilated small-bowel loops with air-fluid levels and relative or complete paucity of gas in the colon favor SBO. Suspected Small-Bowel Obstruction Despite the relatively high accuracy of abdominal radiographs in detecting SBO, CT provides much more information, including the site and cause of the obstruction and complications of SBO. As a result, CT findings generally influence patient management much more than do abdominal radiographs. In light of these inconsistent results, it is reasonable to expect that abdominal radiographs will not be definitive in many patients with a suspected SBO. Radiographs could prolong the evaluation period. Therefore, in patients with a known or suspected SBO, fluoroscopic-contrast examinations (SBFT, conventional enteroclysis), and particularly, cross-sectional imaging examinations (CT, MRI, ultrasound [US]), as well as specialized cross-sectional imaging examinations (CT enterography, CT enteroclysis, MR enterography, and MR enteroclysis), may be more useful options for diagnosis. Variant 2: Suspected intermittent or low-grade small-bowel obstruction. Indolent presentation.