It is a conjunctival training in the shape of triangle. It can remain still, or progress slowly in several years towards the center of the cornea.
It is more frequent in the occupations exposed to the bad weather, to the sun, to the dusts, to the small traumas cf at the masons and the farmers…
No medical treatments effective. The only treatment is surgical, when we notice that it progresses or that it becomes annoying by repeated redness.