Well, according to some experts, corneal ulcer can be dangerous, and what is dangerous is that it may lead to vision loss. Generally speaking, when the clear coating and cornea has been rubbed or irritated by some bacteria, there will have a small tear or cut in your eyes. And we can say that is eye ulcers. For the causes, blepharitis is one of the most common eye infections and often extremely irritating. And it can just cause eye ulcers. To treat it, you can use a cold compress and Ibuprofen to prevent eye pain. And the eye drop should be dropped frequently. But in my opinion, you should have an eye test as soon as possible. Anyway, just be careful about it.