Sinus Trephination

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 diseases causing damage to the delicate structures in the nose, Pseudomonas can take hold and cause significant infections that get deep into the bones of the nose and sinuses. Over the years, they can cause a lot of damage to normal bone and tissue. As bacteria, they are also very effective at becoming resistant to standard antibiotics.

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.

• In many cats with Pseudomonas infection, the infection gets in the sinuses, which are air-filled spaces in the skull behind the eyes and nose. Once these infections are established in that location, it is very difficult to clear them, as normal antibiotics will not penetrate easily into the tissue.
• On a CT scan, we identify the involvement of the sinuses, which helps to direct which side (they are on the left and right sides) requires treatment.

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 frequently send off samples to the laboratory to confirm the type of infection and which antibiotic the infection is sensitive to.

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

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 material leaks to the space behind the eye (retro-orbit) or possible adverse reactions to the antibiotic itself.

• Yes, it is possible that this procedure would cause some discomfort. However, it is likely that your cat already has a significant headache from its 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 painkillers. 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.

• We have had 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 when your cat is comfortable, and their symptoms are mild.
• Currently, cats seem to require this treatment every 6-12 months.

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