| When there are some disorders or diseases on our | | | | Known as the peripheral form of Keratoconus, PMD |
| eyes, the cornea shape will change. So doctor uses | | | | means a lobster claw pattern by breaking down of the |
| corneal topography to map the cornea to check | | | | cornea. So we can see PMD and Keratoconus are in |
| Keratoconus and other progressive eye diseases. And | | | | the same family and not easy to distinguish them. |
| it is proved corneal topography is one of the best way | | | | However, PMD still has its own specific feature. You |
| to test the cornea and diagnosis of eye diseases. The | | | | can distinguish PMD from the steepening, which is from |
| following will give some introduction on how to use | | | | the outer margin of the cornea heading inwards, like |
| corneal topography to check Keratoconus. | | | | pinching the center. And the signs of PMD are as |
| For people with healthy cornea, the cornea in the | | | | following: Compared with Keratoconus, people can not |
| corneal topography is smooth and flat, and there is a | | | | feel pain with PMD. However, they can feel their visual |
| 90 degree axes perpendicular in the cornea. And if | | | | distortions. In addition, there is no vascularization of the |
| there is any irregularities, that means there are some | | | | cornea and no scarring. And there is lobster claw |
| problems with the cornea. For example, irregular | | | | formation with PMD. |
| astigmatisms can be diagnosed if there is steepening | | | | Just as other eye diseases, the regular test at the eye |
| or irregular shaping of the axes. When doctors use | | | | doctor is critical for Keratoconus. Therefore, visit your |
| corneal topography to check Keratoconus, they can | | | | eye doctor at a regular time and have a baseline |
| make a judgment from "Inferior Steepening". For | | | | corneal topography. The corneal topography can tell |
| people who have corneal astigmatism, their shape of | | | | you if you are far away or bothered from |
| the cornea is like a football, while for normal ones, it | | | | Keratoconus. If you are unlucky to have this kind of |
| should be round and smooth. | | | | eye disease, the test can help you to treat or stop the |
| In addition, Keratoconus has some similarities with | | | | progression of Keratoconus in time, and finally to help |
| Pellucid Marginal Degeneration (PMD) from the corneal | | | | you to have a good treating result. So please don't |
| topography, which may cause people some confusion | | | | forget to visit your eye doctor and have your eyes |
| about them. Dr. Schalaeppi discovered PMD in 1957. | | | | checked at a regular time. |