For the most part brown spots on the eye are harmless. Brown spots on the eye are caused by a clumping of pigment cells, similar to how freckles or moles form on the skin, some people are born with these spots.
A brown spot on the eye’s white part is often called a Nevus (or nevi, plural). The Nevus is made up of Melanocytes, which are the cells that produce melanin, the pigment colors are hair, eyes, and skin.
In sporadic cases, the brown spot could be a type of cancer known as ocular melanoma. It can occur in the middle layer of the eye.
The exact cause of ocular melanoma is unknown. Ocular melanoma starts as melanocytes. It is thought to have multiple factors, including:
• Exposure to UV light
• The environment
Just because ocular melanoma is found in rare cases. If you see a brown spot appear on your eye, it is best to have it evaluated with a thorough clinical examination, eye examinations, including slit lamp biomicroscopy, indirect ophthalmoscopy ultrasonography, fluorescein angiography, and optical coherence tomography (OCT).