How is Keratoconus Diagnosed?
The initial symptoms of keratoconus include frequent and significant changes in a patient’s eyeglass prescription, especially in the amount of astigmatism. This is often followed by progressive vision problems such as halos, glare symptoms, ghost images, double and multiple images perceived by each eye individually, and by numerous attempts at obtaining a good glasses prescription without success.
Early diagnosis is very important in the management of keratoconus. New advanced technologies allow eye doctors to detect and treat the condition very successfully. The most sensitive diagnostic method available for keratoconus detection is corneal topography. This allows the doctor to evaluate the shape of the cornea. The most commonly used topography instruments only measure the front surface of the cornea; however more advanced forms of topography evaluate both the front and back surface of the cornea as well as corneal thickness profiles. This is critically important since the earliest abnormalities found in keratoconus will develop initially on the back surface of the cornea and tend to always be more advanced than the front surface irregularities. Other diagnostic tests may also detect keratoconus at very early stages and also discover progression early on. These include aberrometry techniques which measure various forms of visual distortion, and corneal optical coherence tomography (OCT) which provides exquisitely detailed imaging of the cornea.
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Pentacam Corneal Topography measuring both the front and
back surface of the cornea as well as corneal thickness profiles.
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Aberrometry measures vision distortions in keratoconus
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Optical Coherence Tomography (OCT) keratoconus