So your vet has decided it's time to get things moving and take a look into your dog's digestive system by using contrast x-rays. Unlike plain x-rays, contrast x-rays offer a different insight of what may be really happening inside your dog.
If your dog ate something made of fabric such as socks, underwear or pantyhose, it won't likely show up in a regular x-ray, but a barium study may pinpoint the area of trouble by pinpointing slower transit times.
For contrast x-rays, your vet may use either barium or iodinated contrast medium. For vomiting dogs, barium sulfate remains the most utilized contrast medium. Perhaps this is because the many advantages it offers. Barium adheres very well to the dog's GI mucosa, but without being absorbed, it doesn't irritate, it provides a good level of contrast and it's low cost, explains Johnny D. Hoskins, a veterinarian specializing in internal medicine. However it also has its disadvantages. It may be irritating to if there is leakage from the peritoneum and it can lead to aspiration pneumonia if inhaled.
On the other hand, iodinated contrast media, offers the advantage of rapid transit times and unlike barium, it doesn't irritate if there's leakage from the peritoneum. It's therefore the medium of choice should a GI perforation be suspected. When it comes to disadvantages, it doesn't coat well as barium, it's more readily absorbed, it draws fluid into the GI tract, and last but not least, it has a bitter taste.
Contrast x-rays using liquid barium can be helpful in evaluation of gastric emptying. Normally, the dog's stomach should start emptying within 15 minutes post barium ingestion and finish emptying within 2 hours. Within 3 to 12 hours, the barium should move to the colon, which is why most dogs poop twice a day. However, in some cases the barium may transit very fast (hypermotility) or very slow (hypomotility).
What Happens During the Procedure?
[adinserter block="4"]The dog swallows the dense contrast medium or it's introduced through a tube. After ward, several x-rays are taken on a frequent basis to watch the barium move through the digestive tract. The barium shows as white on x-rays and helps make the lining of the digestive system visible allowing the vet to see if there are any narrowed points anywhere along the digestive tract or if there are obstructions, foreign bodies, masses or ulcers. If there's a total obstruction, the barium's progress through the digestive system would stop there; whereas, with a partial obstruction it would move quite slowly.
In some cases, the barium may be mixed with food (barium meal) after the dog has fasted so to study the movement in the esophagus and detect any narrowing points or dilated areas.In some cases, the dog may need sedation or the use of a light anesthetic.
Contrast studies can be performed using video-x-rays, a procedure known as fluoroscopy. Fluoroscopy points out the movement of the medium through the dog's esophagus and stomach, allowing the vet to notice any abnormalities in these structure's muscle coordination. Because this type of test is mostly available in referral practices, your vet may have to refer you to a veterinary radiologist or a specialist in internal medicine.
How much does a barium test generally cost? Expect to spend anywhere between $300 and $900 dollars. It's sure expensive, but one must consider all the time and effort spent at the vet's office getting x-rays done anywhere from 6 to 24 hours. Of course, a barium study shouldn't be the diagnostic test of choice for dogs who are doing very poorly since time is being wasted in the study whilst delaying important treatment!