Horses can develop sinus infections from many different causes, including tooth problems, infections, and trauma. The most common symptom is abnormal drainage from a single nostril. Radiographs (X-rays) will show fluid inside the many large sinus cavities in the horse's head.
Simply giving the horse antibiotics usually won't work, since most antibiotics won't be able to penetrate the pus and fluid. It's critical to rinse away the material that has accumulated inside the sinus.
Here, we trephine (create a hole into) the frontal sinus of this mare. A catheter (tube) is placed to allow repeated rinses and clearing of the material in the sinus.
The horse in the video has had sedation, pain control, and local anesthetic. She feels no pain, and was quite bright and happy both before and after the procedure. We can expect an excellent outcome for her once the infection is cleared.