Corneal Ectasia

Corneal ectasia is a condition resembling keratoconus but comes from a different origin. Almost invariably the cause is refractive eye surgery, most commonly LASIK but also PRK. After LASIK, the cornea has been made thinner. Because the corneal “wall” has been made thinner, internal pressure from within the eye can cause expansion or distension of the cornea.

What causes ectasia and which surgery is it associated with?
Ectasia is specifically associated with LASIK because LASIK penetrates the cornea much more deeply than other procedures (due to the thick stromal flap) and therefore can result in excessive thinning and structural compromise of the cornea.

Symptoms & Diagnosis
Post Refractive Cornea ectasia is identified topographically as a central or paracentral progressive steepening. This is associated with a posterior corneal as seen on topography. Patients may notice:

• Progressive myopia (near sightedness)
• Progressive Irregular astigmatism
• Ghosting vision / blurring vision
• Fluctuating vision
• Problems with vision in darkness /dim lighting
• Eyes at high risk of corneal ectasia following LASIK may have unstable refractions and variable posterior surface bowing prior to developing frank ectasia.

What is the progression and the potential results to the patient?
Ectasia is typically diagnosed sometime in the first two years after surgery but has been known to first be diagnosed later than that. It is a progressive condition and depending on patient particulars and what measures are taken, may progress rapidly or slowly, but typically it will progress over a period of years.

How can ectasia be treated?
There are both surgical and non surgical treatments to mitigate the symptoms of ectasia and attempt to prevent its progression.