Endoscopy of dogs and cats

Endoscopy of dogs and cats makes it possible to see inside the body without surgery. The examination is useful in the investigation of many diseases, but is rarely the first thing we use when a sick animal comes to the clinic – blood tests, clinical examination and imaging usually come first.

The endoscope is a thin instrument with its own light source and camera. The image is displayed in high resolution on a screen through our Karl Storz Vet Telepack, so we can take pictures and video along the way and show you what we see. We have two types of scopes: one rigid and one flexible. Together, they provide access to the nose, ear canals, trachea and bronchi, esophagus, stomach, anterior part of the small intestine, colon and rectum, as well as the vagina and bladder.

Endoscopy of dogs and cats is performed under anesthesia.

At A-Vet, these endoscopic examinations are performed under general anesthesia. The examination requires the patient to lie completely still while the instrument is inserted, and it would be both uncomfortable and frightening for an awake animal. General anesthesia also makes it possible to work thoroughly enough to get what we are looking for, and to take the tissue samples that are often crucial for the diagnosis. You can read more about how we set up and monitor anesthesia in dogs and cats.

Rhinoscopy – examination of the nose

Disease in the nose can manifest as sneezing, sniffling, discharge from one or both nostrils, nosebleeds or swelling. Rhinoscopy is most often part of a larger investigation, together with imaging such as X-ray or CT, cytology of cells from a nasal wash, and, if necessary, microbiological samples.

During the examination, we look directly at the mucous membrane of the nasal cavity and can find inflammation, foreign bodies such as ears of corn, blades of grass or small twigs, and tumors. The scope has a separate working channel, so that we can take tissue samples for histological examination and in many cases remove foreign bodies under the same anesthesia.

Grass in the nose is a common problem in cats. It can cause mild sneezing and sniffling, but some cats become clearly unwell, with vomiting, dehydration and a severely reduced general condition. In the summer, we have one to two cats a week with grass in their nose. The reason is usually that the cat eats grass and then vomits it up – the blade of grass is then carried up behind the soft palate and gets stuck in the nasal cavity. It can often be removed with forceps from the back of the mouth, but sometimes we have to use forceps through the working channel of the scope.

Scopy of the airways

Examination of the respiratory tract is relevant in cases of prolonged cough, cough that does not respond to treatment, acute cough where we suspect a foreign body, difficulty breathing, or findings on a chest X-ray. The scope provides insight into the trachea and the largest bronchi. Tracheal collapse in small dog breeds and asthma in cats are two conditions where the examination can be included in the evaluation. In the case of tracheal collapse, we can assess dynamic changes in the airways, while lavage and cell examination from the lower respiratory tract can provide important information in the evaluation of asthma and other inflammatory respiratory diseases in cats.

We often also perform a lavage sample from the lower respiratory tract. We then introduce a measured amount of sterile physiological saline solution and carefully aspirate it back immediately. The amount is adjusted to the patient's size, which areas are to be examined and how the patient tolerates the procedure. The fluid that returns contains cells and any bacteria from the respiratory tract, and can be sent for culture or evaluated under a microscope to clarify what kind of inflammation it is.

Gastroscopy and colonoscopy – stomach and intestines

Belching, prolonged or bloody vomiting, diarrhea, bloody diarrhea, weight loss and pain during defecation are among the reasons to examine the digestive tract with a scope. We examine the stomach and anterior small intestine, large intestine, or both. When investigating chronic intestinal disease, it may be appropriate to examine both the upper and lower parts of the digestive tract under the same anesthesia. Which areas are examined are determined based on symptoms, findings and the problem in the individual patient.

The preparations are different from fasting before general anesthesia. Here, it is not only about safety, but also about emptying the digestive tract so that the mucosa is actually visible - food and intestinal contents hide the very thing we are going to assess. How extensive the preparations are depends on which part is to be examined: with gastroscopy, the stomach must be empty, while examination of the colon requires more, with food restriction for a longer period of time and irrigation fluid according to a specific protocol. You will receive specific instructions from us in advance.

We start in the esophagus, move into the stomach and as far into the duodenum as the scope can reach. Then the animal is turned over and we examine the large intestine up to the junction between the small and large intestines.

Along the way, we take several small tissue samples from each area we examine. The number depends on which parts of the digestive tract are included, and on the quality of the samples. Professional guidelines for the investigation of chronic bowel disease recommend a significant number of biopsies from each anatomical area, because disease changes can be unevenly distributed and because the mucosa can look completely normal even if microscopic examination shows disease. In our case, it is not unusual for a full examination to yield 25 to 30 samples in total. They are sent for histological evaluation by a pathologist, and are often at least as important as what we see with the scope.

The examination can reveal inflammation of the stomach, ulcers, foreign bodies and tumors. In some cases, we can remove foreign bodies with the scope, so that the patient does not have to undergo surgery. A good examination beforehand is still important. Blood tests and imaging diagnostics such as X-ray and ultrasound often included before endoscopy.

Video otoscopy and ear irrigation

For the ear canal, we use a rigid video otoscope from Karl Storz. The instrument has a working channel for irrigation, suction, brushing and forceps, and the image is displayed on a screen while we work. Because we can see what we are doing the whole way, the cleaning can be done in a targeted manner, and we can assess the eardrum when the ear canal is clean – something that cannot be done reliably in an ear full of secretions.

The dog in the video below has otitis externa, i.e. inflammation of the skin in the outer ear canal. The cause of ear inflammation is complex and is usually divided into primary causes, predisposing, secondary and maintaining factors. A narrow ear canal and a lot of hair in the ear canal are predisposing conditions: they provide poorer ventilation and more moisture, and make the ear more vulnerable – but they are rarely the entire explanation alone. We go through this in detail on the pages about ear infection in dog og ear infection in cat.

In the video you can see how we use flushing, suction and angling the instrument to loosen and remove a lump of old earwax, and how a soft brush removes debris and hair along the canal. The forceps are used when something needs to be grasped precisely. Cleaning under visibility provides a better starting point for further treatment than cleaning without, because we can see both what is being removed and what the ear canal looks like underneath.

Endoscopy is a useful tool in the evaluation of selected patients, and part of the overall diagnostic equipment we have at the clinic. Please contact us if you are wondering if this is applicable to your animal.