ELI5: Explain Like I'm 5

Myopic crescent

So you know how when you look through glasses or a telescope, things look bigger or closer than they actually are? Well, sometimes people's eyes are shaped funny, kinda like a football instead of a basketball. This can cause things to look closer than they really are even when they're far away.

When the eye is shaped like that, it can cause a little spot in the back of the eye to not get the nourishment it needs. That spot is called the optic disc, and scientists use this spot to study people's eyes. But when the eye is shaped funny, it can cause a crescent-shaped area around the optic disc that is lighter in color than the rest of the eye. That's called a myopic crescent.

It's important for doctors to know if someone has a myopic crescent because it can make it harder to see things far away. But with glasses or contacts that fix the problem, people with myopic crescents can see just as well as everyone else!