Is Your Nearsightedness Really Just Increasing? Or It Is Keratoconus?

One of the most common signs of keratoconus is frequent change of eyeglasses. It is common to find the need to change your glasses due to constant increase of prescription. You may find that in a year, you need to have your lenses changed at least twice, and in most cases, you are always not satisfied with the vision your new glasses give you. Your nearsightedness keeps on increasing and you do not know what to do.

In early stages, keratoconus can mask itself as just a simple error of refraction specifically nearsightedness and astigmatism. A characteristic of a keratoconus cone is having a steep cornea, and this will cause the light to converge in front of the retina, causing nearsightedness. And because the changes on the cornea can be uneven, irregular astigmatism is being created.

In mild cases, patients can still achieve a 20/20 vision while wearing their glasses and eventually as the disease progresses, vision is not correctable to 20/20 anymore. One may notice slight shadowing of letters during their visual examination. Recently, we have just seen a keratoconus patient who can achieve 20/20 vision with his glasses. With the keratometer instrument, you would not notice that he has keratoconus. No distortion of corneal mires, beautiful numbers within the norm, but seeing his script, you would have a clue that something is just not right. Of course one has to do comprehensive examination, so we pop the patient in front of the corneal topographer and sure enough, his cones are located inferior to his line of sight, sparing his vision.

A. Normal vs Keratoconus Topography

So indeed, nearsightedness and astigmatism are considered common errors of refraction, but looking at it more closely can change how the case will be managed.

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