Mechanical small bowel obstruction (SBO) characteristically has multiple loops of dilated, centrally positioned bowel. There are frequently numerous loops of tight curvature. These are clearly seen when gas filled, but can be very much more subtle should they be fluid filled. An erect film demonstrates multiple air-fluid levels. If loops are predominantly fluid filled then only a few scattered gas bubbles may be seen trapped against the mucosal surface. This is known as the 'string of beads' sign and is a useful sign in confirming SBO in the otherwise gasless abdominal radiograph. A paucity of large bowel gas can be a helpful sign.

Although SBO usually occurs due to post-surgical adhesions or inguinal hernia, other aetiologies will give similar appearances and these cannot be easily differentiated on the plain AXR. In cases of SBO, the hernial orifices should be scrutinised for incarcerated bowel. Gallstone ileus is a rare cause of SBO which can give a classical appearance on AXR. This occurs when a large gallstone (over 2.5cm) passes from the gall bladder into the small bowel. If the stone is calcified then it may be seen on the abdominal film (see Fig. 2.8). This is usually identified in the right iliac fossa where it impacts in the terminal ileum commonly 60 cm proximal (narrowest part of the small bowel) to the ileo-caecal valve causing SBO. It can be symptomatic when more proximal. Chronic gall bladder inflammation leads to cholecysto-duodenal fistula and stone passage into the duodenum. Stone passage allows reflux of gas into the biliary tree giving a branching gas pattern projected over the right upper quadrant (see Fig. 2.9). At laparotomy the stone containing loop of small bowel is isolated and attempts to crush the stone can be made. If this fails the small bowel is opened proximal to the stone which is milked out.

Fig. 2.8 Plain film gallstone ileus. The impacted gallstone is seen projected over the left sacro-iliac joint. A gas-filled loop of small bowel is present in the left upper quadrant. Faint branching gas shadow in the right upper quadrant. Note also the calcified pelvic fibroid.

Was this article helpful?

0 0
Get Rid of Gallstones Naturally

Get Rid of Gallstones Naturally

One of the main home remedies that you need to follow to prevent gallstones is a healthy lifestyle. You need to maintain a healthy body weight to prevent gallstones. The following are the best home remedies that will help you to treat and prevent gallstones.

Get My Free Ebook

Post a comment