Detection of intestinal ischemia in patients with acute small-bowel obstruction due to adhesions or hernia: efficacy of CT.
OBJECTIVE
The purpose of this study was to determine whether CT can be used to diagnose ischemia of the small intestine in patients with small-bowel obstruction due to adhesions or hernia.


METHODS
During a 12-month period, 60 patients underwent surgery for complete or high-grade small-bowel obstruction due to adhesions or hernia, and 29 (48%) had evidence of associated intestinal ischemia. All of these patients had been preoperatively diagnosed by CT as having high-grade small-bowel obstruction. At the same time, a prospective determination was made based on the CT as to whether there was any associated intestinal ischemia. All CT scans were performed within 24 hours of the operation. A CT diagnosis of ischemia was based on the presence of two or more of the following signs: bowel-wall thickening, high attenuation of the bowel wall on unenhanced CT scans, mesenteric edema or fluid, asymmetric bowel-wall enhancement on i.v. contrast-enhanced CT scans, pneumatosis, or portal venous gas. Results of the CT examination and surgical findings were then compared. Further evaluation was done with a retrospective multivariate discriminant analysis.


RESULTS
Ischemia was prospectively diagnosed on the basis of CT findings in 41 (68%) of the 60 patients. There were no false-negative CT diagnoses (sensitivity, 100%); however, there were 12 CT diagnoses that were false-positive (specificity, 61%). The multivariate analysis corroborated the prospective results by showing high sensitivity (90%) and diminished specificity (50-64%). Bowel-wall thickening and high attenuation of the bowel wall were the most important signs of ischemia on unenhanced CT scans, whereas abnormal bowel-wall enhancement and mesenteric fluid correlated best on enhanced CT examinations.


CONCLUSIONS
CT is a sensitive but not completely specific preoperative indicator of intestinal ischemia in patients with small-bowel obstruction due to hernias or adhesions.
Frager
D
D
Department of Radiology, Columbia University College of Physicians and Surgeons, St. Luke's-Roosevelt Hospital Center, New York, NY 10025, USA.
Baer
J W
JW
Medwid
S W
SW
Rothpearl
A
A
Bossart
P
P
D000208:Acute Disease; D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D005260:Female; D006555:Hernia, Ventral / Q000150:complications*; D006801:Humans; D007415:Intestinal Obstruction / Q000150:complications*; D007421:Intestine, Small / Q000098:blood supply* / Q000000981:diagnostic imaging; D007511:Ischemia / Q000000981:diagnostic imaging* / Q000209:etiology*; D008297:Male; D008875:Middle Aged; D015999:Multivariate Analysis; D011446:Prospective Studies; D012189:Retrospective Studies; D012680:Sensitivity and Specificity; D000267:Tissue Adhesions / Q000150:complications; D014057:Tomography, X-Ray Computed