Bullous Keratopathy
Disease Description and Clinical Picture
Bullous keratopathy represents the appearance of bullae on the cornea (smaller or larger blisters) that can as a result of the corneal endothelial disease (endothelial dystrophy or endothelitis), or can develop as a result of the aggressive corneal stromal inflammation and collagen degradation. If the corneal endothelium is unable to maintain normal fluid transport, it leads to the accumulation of excess fluid in the cornea, followed by edema and the formation of bullae. Less commonly, a bulla on the cornea can be observed in infectious keratitis (keratomalacia). In this case, enzymes originating from bacteria, damaged corneal cells, and inflammatory cells damage the corneal structure, making it thinner, softer, and prone to the formation of bullae. Bullous keratopathy in cats occurs as a result of an aggressive immune response, where the immune system attacks corneal collagen, and generally occurs in cats receiving topical or systemic immunosuppressive drugs.
 
When the bullae burst, very painful ulcers can form. They can become infected, and the process can extend to the deeper layers of the cornea and lead to the formation of a descemetocele, when only Descemet's membrane prevents eye rupture. In some cases very aggressive course of the disease is present resulting in corneal perforation and the need for emergency corneal repair surgery.
 
Therapy
The therapy aims at stabilizing enzymatic processes by using serum, tetracyclines, EDTA solutions, and N-acetyl cysteine. Local anticollegenases and antibiotics are applied. Surgically, the edematous corneal tissue can be covered with conjunctiva or third eyelid flap (feline bullous keratopathy). If the bullae have formed due to endothelial dystrophy, the therapy indicated for endothelial dystrophy is applied (for more details, please see sections on corneal endothelial dystrophy and corneal endothelitis).
 
Please contact our specialty veterinary ophthalmology hospital Animal Eye Consultants
of Iowa (animaleyeiowa@gmail.com) in USA or Oculus Veterinary Specialty Hospital
(oculusklinika@gmail.com) in Serbia, Europe to schedule an appointment so your pet
can be seen.