Case 6: Fungal Keratitis
Cody is a 20-year-old Quarter Horse stallion that was first seen by North Florida Equine for a painful, tearing left eye. His owner had been treating the eye with ointment for two days. When she noticed no improvement and possible deterioration of the situation, she called North Florida Equine for an exam. Cody was diagnosed with a superficial corneal ulcer. The topical antibiotic was changed and a dose of atropine was given to dilate the pupil. Cody was also started on oral banamine for the pain. Recheck was scheduled for Monday.
Four days after initial presentation: Recheck
On recheck, Cody’s eye was very painful. He was holding the eye almost closed and there was discharge and moderate swelling around the eye. His pupil was no longer dilated. Corneal edema (the blue haze) was present and a white plaque had formed over the ulcerated area. The ulcer was not healing, and even worse, the cornea also appeared to be in the early stages of “melting”. This is an indication of severe infection. A sample was collected from the cornea for cytology. Fungal hyphae were identified.
Diagnosis: Fungal Keratitis (keratitis = inflammation of the cornea)
Fungal infections of the cornea require VERY intensive treatment that includes application of multiple medications every two hours around the clock. Cody’s owner was committed to the intensive treatment, so a subpalpebral (under the eyelid) lavage system was placed under Cody’s upper eyelid. Cody was started on a barage of eye medications including an antibiotic, an antifungal, medication to dilate his pupil, and medications to stop the melting of the corneal suface.
Cody and his subpalpebral lavage system. A port is attached to his mane and small tubing delivers the medication through the eyelid and directly onto the cornea.
7 days after presentation: Beginning to Heal
14 days after presentation: A Step Backwards
Earlier in the week, it was decided to discontinue one medication to give Cody’s owner a bit of a break with the treatment schedule. Discontinuing just one medication doesn’t sound like much, but treating this eye was time intensive, and any bit of relief made a difference. The eye appeared to substantially worsen. Pus developed in the anterior chamber of the eye and the pupil constricted, both signs of inflammation inside the eye. The discontinued medication was quickly restarted and the antibiotic regimen was altered.
Can you see the layer of white settling to the bottom of the inside of the eye? The medical term for this pus inside the eye is hypopyon.
22 days after presentation: Back on Track
On recheck healing appeared to be back on track. The signs of inflammation within the eye had gone away with the pus no longer evident and the pupil dilating well.
33 days after presentation: Recheck
Cody’s eye remained comfortable. There was no stain uptake (staining reveals corneal damage – see May’s Case of the Month for more details) and the surface of the cornea appeared smooth and the closest to normal since the process began. All treatments were continued but they were decreased to four times daily.
40 days after presentation: Is it safe to stop the treatments?
Cody’s cornea continued to heal and the infection appeared to have resolved. On exam the pupil was dilated and there was no stain uptake, all that remained of the infection was a large white scar. The lavage system was removed. Cody’s owner continued to keep a close watch for any evidence of pain or constriction of the pupil and noticed neither.
9 weeks after presentation: Recheck
Cody’s cornea continues to remodel. He does not show any sign of pain and has vision in the eye. The scar is very obvious on the corneal surface as seen in the picture above.
Just over 4 months after presentation
North Florida Equine was at the farm a few weeks ago to see another horse and we took a quick peek at Cody’s eye. The scar continues to decrease in size and Cody is comfortable, happy, and appears to have normal vision in that eye.
After many long days (and nights!) of treatment – Cody is a success story, thanks in no small part to the hard work and dedication of his owner.