Rhinoscopy

Rhinoscopy is examination of the nasal passages using two speciali cameras: a rigid camera for insertion into the nasal passages and a flexible endoscopic camera for examination of the back of the nose and oral cavity.

Rhinoscopy is used to evaluate cats with sneezing, nasal discharge or changes to the structure of the bones of the face.

Rhinoscopy is important in the diagnosis of cats with nasal cancer, fungal disease, foreign bodies and chronic rhinitis.

Rhinoscopy is often combined with a CT scan of the nose as some areas of the nasal chambers and sinuses cannot be reached with the cameras.

All rhinoscopy is performed under anaesthesia.

Most patients will also have nasal biopsies obtained during the procedure and this can result in some bleeding from the nose.

Patients may be required to stay overnight in the hospital depending on the findings during rhinoscopy.

There is often a long list of patients requiring endoscopy on any given day. Typically we will send you an SMS to advise you of the time your cat will have their procedure and your feline clinician will contact you once we have performed the investigation.

Specialised cameras are used to evaluate inside the back of your cat's nose.

Rhinoscopy allows for further investigations of cats with nasal discharge and helps identify diseases such as foreign bodies, chronic infectious and inflammation, fungal disease and cancer.

This image shows relatively mild inflammation. There is a little bit of mucous on the right side but otherwise changes are minimal.

This image shows more obvious nodules of inflammation.

QUESTION AND ANSWER

What is rhinoscopy?

Nasal endoscopy or rhinoscopy is a procedure used to look at the inside of your cat's nasal cavity and sometimes the sinuses. Our feline veterinarians insert an endoscope (a long tube with a camera and a light) into the back of your cat's nose through their mouth and also up into their nose. The camera captures video images and projects them onto a screen.

Why have I had rhinoscopy recommended for my cat?

Rhinoscopy is recommended to investigate a cat who has had chronic sneezing and nasal discharge. It is used to identify rhinosinusitis (nasal and sinus inflammation or infection), nasal polyps, nasal cancer and fungal infections. It is also used to remove foreign objects such as grass, seeds or even insects!

Does my cat need a CT with their rhinoscopy?

CT imaging and rhinoscopy complement each other very well and give us the full clinical picture of what is happening in your cat's nose and sinus cavities. A CT scan gives us detailed anatomic information about the structure of these areas and we cannot reach all of these areas (such as the sinus) in cats due to their size. Sometimes areas of disease are only seen on CT. Rhinoscopy allows your veterinarian to evaluate the nose from the inside and obtain samples for testing. It also allows removal of foreign bodies if they have been identified. We will discuss with you at your cat's appointment whether we think a CT will be beneficial.

What happens when my cat has a rhinoscopy?

Rhinoscopy is always performed under anaesthesia. This is to keep your cat still and also to protect their lungs from the fluid that is used to flush their nose during the procedure.
Once your cat is under anaesthetic, they are positioned to keep their head still while we examine the inside of their mouth and the back of their throat using soft flexible endoscopy cameras.
Images are obtained and any abnormal areas are identified. This is also where many foreign bodies tend to get stuck.
We then change to a rigid camera which is inserted up into their nostrils. We examine the inside of your cat's nose and take biopsies of the nasal tissue for histopathology (looking at the types of cells) and culture (growing bacteria or fungus).
While the rigid camera is inside your cat's nose, there is saline flush running which helps to clear discharge. Cats with very snotty noses often feel better after the procedure as it clears everything out.

Is rhinoscopy painful?

Rhinoscopy shouldn't hurt although sometimes there can be some bleeding from the biopsy sites and cats may sneeze a little more. These symptoms usually resolve on their own in one or two days.

How long does rhinoscopy take?

In most cases, rhinoscopy takes about 30-45 minutes to complete.

What are the risks of rhinoscopy?

In general, rhinoscopy is very safe. Adverse reactions can occur relating to the anaesthetic (if they have other airway related problems) or if disease has spread from the nose to the brain (e.g. cryptococcus fungal infections). CT can be important in helping to identify these changes. We will discuss with you if we think your cat has any additional risk factors.

When do we get the results?

Your feline veterinarian will discuss the results with you on the day. Biopsy results are typically received within 72 hours.

How long does my cat need to stay for?

In cats that are otherwise well, rhinoscopy is generally a day procedure and you cat can go home the same day.

After looking at the back of the nose with the flexible rhinoscope we change to a rigid scope which is inserted up into the front of the nostrils.

This image shows a blade of grass stuck inside a cat's nose. It was pulled out using special forceps.

Blades of grass removed from a cat's nose!

Frontal Sinus Trephination and Instillation of Pluronic Antibiotic Gel for Pseudomonas Chronic rhinosinusitis.

At Cat Specialist Services we are trialling a novel treatment for cats suffering from Pseudomonas infection in their nasal cavity and sinus cavity.

What is Pseudomonas?

Pseudomonas is a type of bacteria that can be a normal part of the bacteria in a cat's nose. However in cats that have had previous cat flu infections or with other underlying disease causing damage to the delicate structures in the nose, Pseudmonas can take hold and cause significant infections that get deep into the bones of the nose and sinuses. Over years they can cause a lot of damage to normal bone and tissue. As a bacteria, they are also very effective at becoming resistant to standard antibiotics.

How is Pseudomonas Chronic rhinosinusitis in cats usually treated?

This is an extremely challenging condition to treat and it is important to note that cats will very rarely be cured of the condition as often the changes to the nasal tissues are permanent and recurrence is common. Many treatments are often tried including a variety of antibiotics and anti-inflammatories. Nebulisation can be helpful to break up nasal discharge. Nasal flushing (under anaesthesia) or eye drops can sometimes help alleviate symptoms however symptoms inevitably return.

How can you tell if the infection is in the sinus?

In many cats with Pseudomonas infection, the infection gets in the sinuses. These are air filled spaces in the skull behind the eyes and nose. It is very difficult to clear these infections once they are established in that location as normal antibiotics will not penetrate easily into the tissue.
We identify the involvement of the sinuses on a CT scan and this helps to direct which side (they are on the left and right sides) require treatment.;

What is trephination?

Trephination is the technique where we place a small hole through the bone into the sinus. We then flush any material out (there is often pus like material) and help improve the drainage from the sinus into the nasal cavity. We will frequently send off samples to the laboratory to confirm the type of infection and which antibiotic the infection is sensitive to.

What is the gel?

The pluronic gel is specially engineered to be liquid when cold and when it warms to body temperature it solidfies into a thick paste. It is a carrier for an antibiotic (typically gentamicin) which is effective at killing Pseudomonas. By instilling the antibiotic into the sinus in this way we are hoping that we will be able to destroy more of the Pseudomonas than by giving antibiotic by tablets alone, particularly as the Pseudomonas may be resistant to many of those types of antibiotic.

Are there any risks?

We have treated a number of cats using this technique now and we have not had any significant complications, however potential risks could include trauma to the eye if there is leakage of material to the space behind the eye (retro-orbit) or possible adverse reactions to the antibiotic itself.

Is this procedure painful?

Yes it is possible that this procedure would cause some discomfort, however it is likely that your cat already has a significant headache from their sinus infection! We will always give your cat pain relief and most cats that have this procedure performed will stay overnight so that we can give them some strong pain killers. They generally go home the following day with pain medications for the next few days.
Most cats don't show any signs of discomfort and are eating well within a few hours of the procedure.

Does it work?

We have had good success with the treatments so far, however it is important to note that we are not aiming to cure your cat (although with mild symptoms this could be possible). Our aim is to get the longest time possible in between treatments where your cat is comfortable and their symptoms are mild.
Currently cats seem to require this treatment every 6-12 months.

How can I get this treatment for my cat?

You would need to organise an appointment with our feline veterinarians. They will assess your cat and discuss the options with you.

Pseudomonas is a bacteria which can cause severe infections in the nose and sinuses of cats with long term nasal disease.

With Pseudomonas infections, thick nasal discharge is often very stuck onto the delicate soft tissue structures of the nasal cavity. Over time, there is destruction of these tissues and surrounding bone and infection can be very difficult to treat.

This CT scan shows a cat with infection in the right frontal sinus (grey filled region at the top of the skull), compared with the left frontal sinus (black filled region at the top of the skull).

A small hole is opened into the sinus and we flush out as much of the infected material as possible and instil a special antibiotic gel that slowly releases antibiotic into the sinus cavity. The gel is liquid when cold and becomes more solid as it warms to body temperature.

A small incision is left where the material was and these rapidly heal.