Irregular Corneas

I recently learned that there may be something coming out soon to help us with cataract surgery in irregular corneas, which is very exciting!

But wait… what is an irregular cornea? It’s actually a little bit harder to explain that I thought it would be, because there are different patterns of regularity. The cornea is, of course, the very front of the eyeball. The most “regular” or basic cornea is one that is radially symmetric for 360 degrees. In other words, the roundness of the cornea is the same no matter the direction from center. It would be trivial to describe irregular corneas if “irregular” meant any departure from that radial symmetry, but it does not. There is also regular astigmatism. The simple analogy that is often used is that a radially symmetric cornea is similar to a round ball, like a basketball or a soccer ball. A cornea with regular astigmatism is similar to a football, in which there are two curvatures of the ball, each 90 degrees apart from the other.

Anything other than those two basic shapes would be considered irregular, and of course there are an infinite number of possible corneas in the irregular category. These corneas make it difficult to calculate the power of the lens implant for cataract surgery. However, as I said, there has been FDA approval of a device that will be coming out soon to help with these situations, so stay tuned!