Much of ophthalmology is simple pattern recognition. If you’ve seen a cat with these striking white lesions on its cornea before you’ll immediately know what the diagnosis is, and if you haven’t you’ll know after looking at this one! What is the diagnosis?
There really isn’t anything this could be apart from eosinophilic keratoconjunctivitis, but if one wanted to be sure, a corneal scrape should show eosiphils like this one, although some cases have a more varied inflammatory cell population. The trouble is not so much diagnosis as treatment. Topical steroid may be effective but often oral megoestrol acetate is the best treatment regime, even given the possible side effects of this drug.