Endoscopy: What It Is, Why Some Pets Need It

Sometimes, your pet can have a condition that’s difficult to diagnose without actually examining an internal organ or obtaining a biopsy, or tissue sample. While this is often accomplished with surgery, in some cases, endoscopy can provide a less invasive alternative.

During this procedure, a veterinarian inserts an endoscope — a tubular instrument with a small camera and light at one end — into an opening of the body. While endoscopic equipment can be used to examine different internal organs such as the airways of the lungs (bronchoscopy), the urinary bladder (cystoscopy) and the colon (colonoscopy), this article will focus on its use in the stomach and small intestine. For dogs and cats, endoscopy can provide a minimally invasive way to help diagnose gastrointestinal conditions such as inflammatory bowel disease (IBD) and certain types of cancer, such as gastrointestinal lymphoma.   

Why Your Veterinarian May Recommend It

What if your dog or cat is losing weight or experiencing vomiting and/or diarrhea for no obvious reason? Initially, your veterinarian may perform blood tests to help rule out a metabolic cause for the weight loss and other symptoms. If the test results are normal, an X-ray or ultrasound may be performed to further evaluate internal organs such as the liver, kidneys, spleen, urinary bladder, stomach and intestines. In patients with GI (gastrointestinal) disease, the stomach and small intestine can appear completely normal on X-rays or ultrasound. But if your veterinarian still suspects GI disease as the culprit for your pet’s symptoms, GI biopsies may be recommended to confirm a diagnosis. 

GI biopsies can be obtained in a number of ways, such as through an abdominal surgery, via a laparoscopic procedure (in which a fiber optic instrument is inserted through a smaller abdominal incision) or through endoscopy, which is the least invasive method of the three. 

How Does Endoscopy Work?

In human medicine, this procedure is typically performed with the patient under light sedation. Because dogs and cats don’t understand that the veterinary team is trying to help them, they are typically not as cooperative as people, so general anesthesia is required.

While the pet is under anesthesia, the endoscope is inserted into the mouth and then passed through the esophagus into the stomach. Using the small camera on the scope, the veterinarian will examine the stomach for abnormalities. The scope is then advanced into the upper portion of the small intestine (called the duodenum) and passed as far down the duodenum as possible. Due to the length of an animal’s small intestine and all of the twists and turns, it’s not possible to advance the scope through the entire GI tract. 

Once the veterinarian has examined the GI tract, he or she will pass small biopsy forceps through a channel inside the scope. Using the forceps, multiple tissue samples for biopsy can be obtained from the stomach and small intestine and submitted for histopathology, or microscopic analysis, to confirm a diagnosis. The tissue samples taken are relatively small and do not require sutures. Once the biopsies are obtained, the scope is removed and the patient is recovered from general anesthesia.

The Pros and Cons of Endoscopy

Compared with other methods of obtaining GI biopsies, endoscopy is less invasive and relatively quick to perform, so the patient can usually be discharged a few hours after the procedure. The procedure generally doesn't require an overnight stay in the hospital.

With endoscopic biopsies, there is no abdominal incision. Other methods, such as surgery, require an abdominal incision, which means a longer recovery and healing period.

Another benefit to endoscopic biopsies is that some treatments  can be initiated immediately following the procedure. For example, with some inflammatory GI diseases, steroids are often part of the initial treatment. Because steroids can delay healing of surgical incisions, they cannot be started immediately following an abdominal surgery. They can, however, be given shortly after endoscopy, which allows your pet to get started on treatment sooner.

Endoscopy is not beneficial if the abnormality is further down in the GI tract, as the scope will most likely not reach that far (in that case, a colonoscopy may be recommended). Endoscopy is also not able to biopsy anything outside of the GI tract, so if other abnormalities are noted on ultrasound, such as enlarged lymph nodes, these won’t be accessible with endoscopy.

If you have any additional questions about endoscopy, consult with your veterinarian. He or she can determine if this is an appropriate diagnostic procedure for your four-legged friend.