The small intestine is responsible for digestion and absorption of food. It is a long series of loops or pipes as long as 25 feet long. The small intestine is between the stomach and colon. The small intestine can become larger in its size or dilated along a segment or throughout. There are many causes of dilated or larger then usual small bowel. Some of the causes may make you sick right away while others may be more chronic or even asymptomatic.
X-rays are a common starting point to investigate symptoms such as pain in your abdomen. These are often ordered by your doctor from his office, or if you are coming to the emergency room. X-rays of the abdomen will show the intestines, if they are filled either completely or partially with gas. The loops of small intestine are often not seen on X-ray if they are filled with fluid and ingested food. In these cases, they will blend with the rest of the abdomen and be invisible.
When the small bowel loops are visible, they may appear dilated or bigger then usual to the radiologist who interprets the x ray. The radiologist will look at the pattern of dilation and try to determine the cause. The most worrisome is a small bowel obstruction. This happens when the a segment of the intestine gets blocked, either partially or completely.
Small bowel obstruction can occur from many causes. One of the most common is when you develop adhesions or scar tissue after surgery which causes a blockage. Often patients are sick with pain and vomiting. A surgeon will often get involved in your care. The X-ray will show big dilated small bowel loops with fluid levels.
Another common cause is called adynamic ileus which is basically a paralyzed intestine which does not propel contents. This can be due to multiple causes such as: drugs, infections/sepsis, surgery, metabolic disturbances, and intestine which is starved of blood supply (intestinal ischemia). The X-ray will show dilated loops of small intestine throughout also with fluid levels. Often the appearance will overlap with that of obstruction of the intestine. Additional imaging studies may be ordered to help exclude an obstruction.
One additional common cause of dilated small intestine can simply be normal for you, Say you just drank a soda or swallowed a bunch of gas. In these cases, you will likely not feel sick. Less common causes of blockages can include a hernia. A segment of the intestine may go into a hernia where it causes an obstruction. This is a mechanical obstruction, meaning it must be corrected by surgery in order to allow fluid and food to get through.
Other less common causes include inflammation such as Crohn’s disease. The inflamed intestine in this condition can become narrowed or scarred. A cancer or benign mass of the small bowel can cause obstruction. Bleeding into the wall of the intestine can cause a blockage. This can occur from trauma or when your on blood thinners for other conditions.
There are a wide variety of conditions that can cause dilated small bowel loops on X-ray from normal to benign to life threatening such as obstruction. Your doctors will be of importance to determine how to proceed after finding dilated small bowel loops on X-ray. This may mean that they do nothing if your feeling well and eating all the way to hospitalization and emergency surgery. A ct scan will often be ordered to get more information to the cause of your dilated small bowel. A hospitalization may follow and a surgeon may also get involved.