The cornea is the transparent, outermost layer at the front of the eye, covering the iris and pupil. It functions much like a clear window, allowing light to enter the eye and helping to focus it onto the retina for clear vision. A “burned cornea” refers to a serious injury to this delicate surface, where the corneal tissue is damaged by various forms of intense energy. This type of injury can significantly impair vision and cause discomfort.
Understanding Corneal Burns
Corneal burns can arise from several distinct sources. Chemical burns occur when corrosive substances, such as household cleaning products, industrial acids, or alkalis like drain cleaners, come into contact with the eye. Alkali burns are often more severe than acid burns because they can penetrate deeper into the eye’s tissues, potentially causing liquefactive necrosis.
Thermal burns result from exposure to extreme heat, such as splashes of hot liquids or steam, or direct contact with flames. Ultraviolet (UV) radiation burns, also known as photokeratitis or “welder’s eye,” happen due to overexposure to intense UV light. Common sources include welding arcs, prolonged sun exposure, and artificial sources.
Individuals often experience severe eye pain, which can range from mild to intense. The eye typically appears red, with blurred or cloudy vision. Sensitivity to light (photophobia) is common. Excessive tearing and a gritty or foreign body sensation are also frequently reported. For UV burns, symptoms may be delayed, appearing 3 to 12 hours after exposure.
What to Do Immediately and Medical Care
Immediate action after a corneal burn is important. For chemical burns, flushing the affected eye with clean water or saline solution for at least 30 minutes is the most important first step. If sterile saline is unavailable, cold tap water can be used.
The eyelids should be held open to ensure thorough irrigation, and it is more important to continue flushing than to delay treatment by immediately transporting the person to the hospital. For any type of corneal burn, avoid rubbing or pressing the eye, and if possible, cover it lightly with a clean cloth. Seeking professional medical attention from an eye care professional immediately after initial first aid is recommended.
Upon arrival at a medical facility, an eye care professional will diagnose a corneal burn through a thorough eye examination. This involves using a slit lamp, a specialized microscope that provides a magnified, illuminated view of the eye’s structures. To highlight any damage to the corneal surface, a dark orange dye called fluorescein is often applied to the eye. When light from the slit lamp is shined on the eye, damaged areas of the cornea absorb the fluorescein and glow bright green or yellow. This technique allows the doctor to assess the location and extent of the injury.
Medical treatment for corneal burns focuses on promoting healing, managing pain, and preventing infection. Antibiotic eye drops or ointments are commonly prescribed to prevent bacterial infections, typically applied four times daily for 5-7 days. Pain relief is managed with oral analgesics, and sometimes cycloplegic eye drops are used to relax the eye muscles, which helps reduce pain and light sensitivity. While eye patching was once a common practice, recent research suggests it may not improve healing or pain relief and is generally no longer recommended, especially for contact lens wearers due to infection risk. In severe cases, more intensive interventions, potentially including surgical debridement, may be necessary.
Healing and Long-Term Considerations
The recovery process for a burned cornea depends on the injury’s severity. Minor corneal burns often heal rapidly, and the cornea has a strong ability to repair itself quickly, often without permanent scarring in superficial cases.
Larger or more severe abrasions may take longer, potentially up to a week, to fully heal. Follow-up appointments with an eye care professional are important to monitor healing progress and rule out complications. Patients should avoid rubbing their eyes and refrain from wearing contact lenses until the eye is fully healed and cleared by a doctor.
Despite the cornea’s healing capabilities, some burns can lead to long-term complications. Corneal scarring can occur, especially with deeper or more severe burns, which may result in persistent blurred vision. Chronic dry eye is another possible issue, arising from damage to the tear-producing cells or glands. Recurrent corneal erosions, a condition where the outermost layer of the cornea repeatedly detaches, can also develop, causing recurring pain, tearing, and light sensitivity, sometimes months or years after the initial injury. While permanent vision loss is rare with superficial burns, severe chemical or thermal injuries can lead to irreversible damage.
Preventing future corneal burns involves adopting safety measures. Wearing appropriate protective eyewear, such as safety goggles or face shields, is advised during hazardous activities. This includes tasks involving chemicals, such as cleaning with strong detergents or working with industrial compounds, as well as activities that produce flying debris. For those exposed to intense light sources like welding arcs or prolonged sun exposure, UV-filtering sunglasses or specialized welding masks are necessary to shield the eyes. Adhering to workplace safety protocols and ensuring proper lighting in work areas also contributes to eye safety.