The cornea is the front, transparent part of the eye. By remaining transparent, light can enter the eye and enable us to see. When fluid accumulates within the cornea, this swelling (oedema) of the cornea results in loss of transparency and clouding of the cornea.
How do I know if I have corneal oedema?You may develop a gradual blurring of vision. In mild cases of corneal oedema, this typically occurs in the morning upon waking up. Vision gradually recovers over the course of the day.
As the corneal oedema worsens, the vision may be constantly blurred. Patients may see halos around streetlights or car headlights, especially at night.
In advanced cases of corneal oedema, the surface of the cornea may develop blisters (“bullae”) that result in pain and risk of infection, as well as irreversible scarring of the cornea. This is a condition that is termed "bullous keratopathy".
Corneal oedema may be caused by:
Diagnosis can usually be made when an ophthalmologist examines the cornea. Measurements of the thickness of the cornea, and microscopic photographs of the cells on the inner lining of the cornea can aid diagnosis.
Treatment of corneal oedema depends on the cause of the oedema, as well as how advanced the swelling is. Patients with high eye pressures or eye inflammation need treatment in order to prevent corneal swelling from being permanent.
In patients with mild corneal oedema and minimal blurring, concentrated (“hypertonic”) saline drops and ointment can help reduce the corneal swelling and minimise impact on daily activities.
However, as the corneal oedema becomes more advanced, corneal transplant surgery may be needed to replace the inner lining of corneal cells in order to restore transparency to the cornea. This form of partial corneal transplant, where only the inner lining of cells is transplanted, can be performed with DSAEK (Descemet Stripping Automated Endothelial Keratoplasty) and DMEK (Descemet Membrane Endothelial Keratoplasty).
In advanced cases of corneal oedema, where there is severe scarring of the cornea, a full-thickness corneal transplant (or Penetrating Keratoplasty) may be required.