A scratched eye, medically known as a corneal abrasion, is a common injury that often causes discharge. The eye’s natural response to trauma frequently leads to a discharge. A sudden overflow of clear, watery fluid is typical of the injury itself. However, the appearance of thicker, colored discharge signals a potentially serious complication requiring immediate attention.
What is a Corneal Abrasion
A corneal abrasion is a scratch on the cornea, the clear, dome-shaped surface at the front of the eye. This injury affects the corneal epithelium, the thin, outermost layer of cells protecting the eye’s interior. Even minor abrasions, caused by dust or a fingernail, are intensely painful because the cornea possesses one of the highest concentrations of nerve endings in the human body.
Immediate symptoms typically include sharp, sudden pain and the persistent feeling of a foreign object trapped under the eyelid. Patients often experience photophobia, a heightened sensitivity to light that makes it difficult to keep the eye open. The eye also becomes noticeably red, caused by the dilation of blood vessels in the conjunctiva.
How a Scratched Eye Affects Tear Production
The initial and most common discharge following a corneal abrasion is an excessive amount of clear, watery fluid, known as reflex tearing. This is a protective, automatic response triggered by the irritation of the exposed corneal nerves. The eye’s lacrimal glands dramatically increase tear production to flush out any remaining debris or foreign particles.
This watery discharge is a normal sign that the eye is attempting to lubricate the injury and wash away potential contaminants. The fluid is clear, thin, and often runs down the cheek, resulting in a noticeably watery eye. This normal, excessive watering must be differentiated from thick, opaque discharge, which is not a direct result of the trauma.
Identifying Discharge that Signals Infection
If a corneal abrasion allows microorganisms to enter the exposed tissue, the scratch can develop into an infection, such as a corneal ulcer. When this occurs, the discharge changes dramatically, signaling a serious complication. Infectious discharge, often called purulent discharge, is thick and opaque, indicating the presence of inflammatory cells.
This problematic discharge may be yellow, green, or gray. It often accumulates rapidly, especially while sleeping, causing the eyelids to stick together due to drying and crusting along the lash line. Accompanying this change are other symptoms that intensify over time.
The pain may worsen significantly instead of subsiding, and the redness and swelling around the eye may increase. A particularly alarming sign of developing infection is a white or grayish spot directly on the cornea. This spot represents an infiltrate of inflammatory cells. These symptoms collectively indicate a condition that can rapidly progress and potentially threaten vision.
When Immediate Medical Attention is Necessary
Any corneal injury warrants professional evaluation to ensure proper healing and prevent infection. Several specific symptoms necessitate immediate medical attention. Sudden or progressive loss of vision, including blurriness or halos around lights, is a red flag. The presence of any thick, colored discharge, such as yellow or green pus, should prompt an immediate visit to a doctor or emergency room.
Urgent care is necessary if the pain becomes severe or if you are unable to open the eye due to swelling or discomfort. Injuries caused by high-velocity objects or organic matter carry a higher risk of infection and require prompt assessment. As a first-aid measure, avoid rubbing the injured eye, and do not attempt to remove any foreign object stuck on the cornea. Gently flushing the eye with sterile saline solution can help clear minor debris, but the priority must be a timely professional examination.