The two main categories are small intestinal obstruction from a focal foreign body, and a linear foreign body such as pantyhose or strings. Linear foreign bodies can be very hard to diagnose, and I’ve found that the signs are much milder on radiographs than in reality. Small intestinal obstruction tends to cause enlargement of part of the small intestine with fluid and/or gas. The finding of two different sizes of bowel loops often means obstruction. Linear foreign body causes plication, or bunching of the small intestine as it tries to move the string along. This produces a characteristic pattern of “u” shaped, or hairpin turns in the small intestine. Sometimes angular gas bubbles are the only things visible on the radiograph.
Ultrasound is also helpful in both cases, especially when it’s early in the time frame, and gas and fluid hasn’t accumulated in the bowel yet. With ultrasound you can also look for smaller objects, and for the presence of fluid in the abdomen that might mean perforation of bowel.
Here are my favorites:
1.This dog decided to eat the unattended ice cream along with the spoon…
2. This cat decided to eat the string from her owner’s bikini. The arrow points to the very subtle plication of small intestine and angular gas shadows.
3. Soda anyone?
4. This is a classic, post-holiday-weekend case. If you look closely, you can see the pattern of the kernels in the corn cob in this dog’s small intestine. The loop of bowel containing the cob is very dilated, while some of the others are more normal in size.