Diagnosis often is made by a cornea specialist because the regular slit-lamp evaluation performed during a routine eye exam with your ophthalmologist may not in fact reveal any changes in your cornea. Instead, the tests performed to check the curvature of your cornea may include:
Computerized videokeratography, which takes pictures of your cornea so a map can be made of the surface while also measuring the thickness of your cornea
Keratometry that uses light and reflection to determine the curvature of your cornea
Eye refraction that relies on special equipment to check for vision problems
Slit-lamp examination, which is the most common test and involves a beam of light directed into your eye so the doctor can see your cornea and retina using a small microscope
These tests give your doctor important clues that can point to a proper diagnosis, including:
Corneal thinning
An iron-colored ring all around the cone, also known as Fleischer’s ring
Stress lines caused by the change in cornea shape, also called Vogt’s striae
Scars at the top of the cone of your eye, also called apical scarring