Corneal ulceration is a commonly encountered problem in veterinary practice. A simple corneal ulcer that involves only loss of corneal epithelium (Figure 1) should heal within 5 to 7 days, provided the underlying cause is identified and treated.
Although many ulcers are caused by trauma, other causes include keratoconjunctivitis sicca, eyelid or eyelash abnormalities, and conjunctival foreign bodies. When an ulcer fails to heal within 1 week, further assessment must be directed toward identifying other potential underlying conditions or the presence of infection. If additional causes are not identified and infection is ruled out, the ulcer may be classified as an indolent (nonhealing) ulcer.
Treatment for nonhealing ulcers (ie, grid keratotomy, superficial punctate keratotomy, superficial keratectomy) is directed toward correcting the underlying microanatomic defect in the epithelial attachment to the corneal stroma. Thus treatment protocols are indicated only for appropriately diagnosed superficial nonhealing ulcers. Because such treatment may be extremely detrimental in the presence of infection, it is imperative that clinicians recognize and diagnose an infected (and therefore complicated) corneal ulcer. Diagnosis of an infected corneal ulcer is based on a combination of clinical appearance, corneal cytology, and corneal cultures.