Definition A corneal ulcer represents a breakdown in the surface cells of the cornea accompanied by an infiltrate. An infiltrate appears to be a whitish opacity in the eye, but in reality, it represents a collection of white blood cells. Ulcers can be infectious or sterile (non-infectious) in nature. Your ophthalmologist can distinguish between the two forms and treat you accordingly. Cause Most infectious ulcers are caused by bacterial organisms and therefore most ulcers are treated as such until proven otherwise. If an ulcer is small, it is typically treated without obtaining any cultures. If an ulcer is large, your ophthalmologist may choose to obtain cultures for further evaluation. Culturing the cornea is a way of identifying which organisms are responsible for the infection. While bacteria are the most common culprits, an infection can be caused by a virus such as herpes or a fungus or even a protozoan. As a rule of thumb, infectious ulcers tend to be extremely painful and rapidly progressive. Risk factors for infectious ulcers include sleeping in or wearing contact lenses for extended periods of time, improper cleaning or handling of contact lenses, having a history of dry eyes, or incurring any trauma to the cornea among many others. Noninfectious ulcers tend to have a milder presentation. In many cases, they represent a vigorous immune reaction to an inciting factor. In many patients, the coexistence of lid margin disease, also known as blepharitis, is the inciting factor. Contact lens wearers can also develop a noninfectious ulcer, but this tends to be a diagnosis of exclusion. Symptoms Patients tend to complain of the following symptoms: pain redness blurry vision light sensitivity discharge contact lens intolerance They may also notice a white opacity on their cornea. Treatment The treatment of corneal ulcers is tailored to the cause. For infectious ulcers, patients are started on medicated eye drops aimed at targeting the specific organism. If the patient wears contact lenses, they are asked to dispose of the current contacts and refrain from further use until the treatment course is completed. If the infection is extensive, the patient may need to be hospitalized for aggressive treatment which can involve taking eye drops every 30 minutes. For sterile or noninfectious ulcers, patients may be placed on a steroid drop along with an antibiotic drop.