A corneal ulcer is a serious medical condition involving an open sore on the cornea, the transparent, dome-shaped surface at the front of the eye. This damage typically results from an infection (bacterial, viral, fungal, or parasitic), often following an injury or improper contact lens use. Since the cornea plays a primary role in focusing light onto the retina, any compromise can rapidly lead to vision loss. A corneal ulcer is considered an ocular emergency demanding immediate and ongoing care to prevent permanent damage.
Subjective Signs of Healing
Patients undergoing treatment should expect a gradual reduction in symptom intensity, indicating the infection is receding. The most noticeable improvement is a decrease in eye pain and irritation, often the first symptom to subside as the surface begins to repair. This lessening of discomfort should be steady, signaling that the initial inflammatory response is stabilizing.
As the infection comes under control, the eye’s appearance begins to normalize with a visible decrease in redness (conjunctival injection). Excessive tearing and watery discharge should also diminish over the first few days of treatment. A reduction in photophobia, or sensitivity to light, is another positive sign, making it easier to tolerate normal light levels.
While significant vision restoration may take longer, patients might experience a subtle improvement in visual clarity. The epithelium, the outermost layer of the cornea, begins regeneration by migrating over the defect to close the wound. This regenerative phase helps restore the smooth surface of the cornea and contributes to the gradual lessening of discomfort.
Indicators of Worsening Condition
It is important to recognize signs that the condition is not responding to treatment or is actively deteriorating. Increasing or persistent severe eye pain, especially if it worsens after initial treatment, suggests the infection is continuing to destroy deeper corneal tissue.
A sudden or progressive loss of vision indicates the ulcer is advancing, possibly due to increased swelling or tissue destruction. Patients should monitor the corneal infiltrate, the white or grayish spot marking the infection site. If this infiltrate grows larger, becomes denser, or spreads, it indicates damage to a wider area.
An increase in pus or thick discharge, or redness spreading to the eyelids causing increased swelling, are concerning developments. In severe cases, inflammatory cells and pus can settle at the bottom of the anterior chamber, forming a visible layer called a hypopyon. The presence of these signs necessitates immediate consultation with the eye care specialist.
How Eye Doctors Confirm Resolution
While subjective improvement is encouraging, confirmation that the ulcer is resolving relies on objective clinical evidence. The primary assessment tool is the slit lamp biomicroscope, which allows the specialist to view the cornea in high magnification and cross-section. This helps determine the precise depth and extent of tissue damage and the underlying inflammatory response.
During follow-up visits, doctors use fluorescein dye, an orange stain that highlights damaged areas where the corneal epithelium is missing. When viewed under a cobalt blue filter, the damaged area glows bright green, allowing accurate measurement of the epithelial defect size. Healing is confirmed when the area of fluorescein uptake shrinks with each examination, demonstrating that epithelial cells are closing the wound.
The doctor also closely monitors the corneal infiltrate, the white spot of inflammatory cells and dead tissue. Resolution is signaled by a decrease in the density and size of this infiltrate, along with the disappearance of inflammatory debris within the anterior chamber. True confirmation occurs when the epithelial defect has completely closed, providing a protective barrier over the deeper corneal tissue.
Long-Term Visual Outcomes
Once the infection is cleared and the epithelial surface has healed, the long-term visual outcome depends on the depth and location of the initial ulcer. The body’s repair process often forms a corneal scar—an opaque area within the corneal stroma. This scarring alters the cornea’s shape and clarity, impacting how light is focused onto the retina.
If the ulcer was superficial, involving only the outer layers, the resulting scar may be minimal and could fade over several months, often leading to a good visual result. If the ulcer extended deeply into the corneal stroma, however, a denser, permanent opacity will remain. A scar situated centrally, directly over the pupil, will obstruct the visual axis and cause a significant, lasting reduction in vision.
For those with residual vision problems, options range from corrective lenses to complex surgical procedures. If the scarring is peripheral or mild, glasses or contact lenses may correct the distortion. When a dense scar severely compromises vision, a corneal transplant (keratoplasty) may be necessary to replace the damaged tissue with a clear donor cornea.