Abdominal adhesions are bands of scar tissue (ﬁbrous or ﬁbrofatty), most often occurring as a complication of previous abdominal surgery.
Adhesions often occur with
- multiple abdominal operations or previous postoperative intra-abdominal complications
- history of intra-abdominal inﬂammatory disease not treated with surgery
- after radiation therapy
Adhesions often form between loops of bowel. They also frequently attach loops of bowel to the parietal peritoneum, mainly the abdominal wall and the subperitoneal organs.
A non-invasive tool for use in the diagnosis of adhesions is desirable, as laparoscopic exploration may result in the formation of more adhesions. Adhesions are only rarely visualized, however. Detection of intra-abdominal adhesions is based on indirect signs or abnormal visceral slide.
Abdominal adhesions are rarely visible on CT, however, CT has proven to be a valuable diagnostic modality in the detection of adhesion-related complications, such as bowel obstruction or bowel ischemia. In the absence of concomitant diseases, an abrupt transition from dilated to collapsed bowel segments may be the only hint of the presence of adhesions that can be depicted on CT scans.
Small bowel follow-through (or enteroclysis) studies may be useful in patients with equivocal clinical symptoms or negative ﬁndings at CT. Sometimes this procedure can be useful to identify the location and the cause of obstruction.
Indirect signs of an adhesion include:
- a bandlike impression on a dilated small bowel loop
- failure of separation of adjacent loops with external manual compression
Other signs include
- distortion of folds with luminal narrowing
- kinking of an entire loop