Glaucoma is an eye condition where the optic nerve, which connects your eye to your brain, becomes damaged. It can lead to loss of vision if not detected and treated early on.
It usually occurs when the fluid in the eye cannot drain properly, which increases the pressure inside the eye and puts pressure on the optic nerve.
Glaucoma is a common condition, but many people won't realise they have it because it doesn't always cause symptoms in the early stages.
It can affect people of all ages, including babies and young children, but is most common in adults in their 70s and 80s. It can also effect animals.

Many people don't realise they have it because it develops slowly over many years and tends to cause a loss of peripheral vision (the edge of your vision) at first.
Both eyes are usually affected, although it may be worse in one eye. Without treatment, it can eventually lead to blindness.

Types of glaucoma

There are several different types of glaucoma.
Some of the main types are:
primary open angle glaucoma – the most common type, which tends to develop slowly over many years
primary angle closure glaucoma – an uncommon type that can develop slowly or quickly
secondary glaucoma – glaucoma caused by an underlying eye condition, such as uveitis (inflammation of the eye)
normal tension glaucoma – where the pressure inside the eye is at a normal level
childhood glaucoma (congenital glaucoma) – a rare type that occurs in very young children, caused by an abnormality of the eye.

-^This was written by Skye (#62529)^-

So, we were thinking that glaucoma'd be a mutation with stages that would come in different kinds of types. Some lions could have it when they are cubs (about 6-12 months old) and develop it over the years. (Maybe this one is rarer and usually it starts to show in adolhood?) Some would start to have cloudy eyes when they are adols and it gets worse.

In the worst cases, lions would go blind. (When they are about 10-11 yrs?) Eyes would also enlarge, because lions can't get any eye drops.

This mutation would be passed. Mother of a healthy cub has it, but that healty cub still has it in their genetics and passes it down to their cub, who will then have it. Blind lions could also pass it down to their cubs.