Small Bowel Enema
The small bowel is a long and tortuous organ which makes it difficult to examine radiologically.
Currently, the best method for examining the small bowel is the small bowel enema. It permits good distension of the small bowel with barium of the appropriate density in a relatively short period of time, and has the effect of making any narrowing of the bowel more obvious as well as showing up signs of inflammation, ulceration and fistula formation optimally. It is particularly useful when Crohn’s disease, adhesions and tumours are suspected clinically.
The examination commences with the administration of local anaesthetic to the nostril and nasal passage on one side. A thin pipe (thinner than a pencil) is introduced into the nose and passed down the oesophagus, through the stomach and round the duodenal loop to the very beginning of the small bowel.
There will be a sensation of pressure at the back of the nose while the pipe is being positioned, but once pipe manipulation has ceased you will be fairly comfortable.
Once the pipe has been satisfactorily positioned a diluted barium mixture is run through the pipe. This allows optimal distension of the bowel and is not uncomfortable. When barium is noted to be entering the colon a series of x-rays of the entire abdomen is taken as well as a series of spot films of the terminal ileum and any area of abnormality. The pipe is then easily removed and further X-rays may be taken.
The entire examination from the administration of the local anaesthetic till the last X-ray usually takes about an hour. The tube is usually in place for at least 30 minutes.
As the barium is dilute there is seldom any difficulty with spontaneous clearance from the bowel. Most of the barium is evacuated over the following 2-3 hours.