Causes of Brown Discoloration of the Eye

Primary Causes of Brown Corneal Pigmentation

Conjunctival melanoma can cause brown pigmentation of the eye, presenting as a painless, flat or nodular, brown lesion on the bulbar or palpebral conjunctiva, according to the American Academy of Ophthalmology 1

Ocular surface squamous neoplasia can present with conjunctival hyperemia and nodules, sometimes with pigmentation changes, as reported by the American Academy of Ophthalmology 1
Sebaceous carcinoma may exhibit yellowish discoloration of the tarsal plate and can be misdiagnosed as a chalazion, as noted by the American Academy of Ophthalmology, although this fact is also mentioned in Praxis Medical Insights, the American Academy of Ophthalmology is preferred 2
Vasculitis conditions like sarcoidosis can cause various ocular manifestations including iris nodules and trabecular meshwork nodules, according to the American Academy of Ophthalmology 3

Slit-lamp biomicroscopy is essential to evaluate the location and depth of pigmentation, as well as associated findings, as recommended by the American Academy of Ophthalmology 4

Enlargement of a pigmented lesion, development of blood vessels, or thickening requires urgent evaluation, as warned by the American Academy of Ophthalmology 1
Recurrence of pigmented lesions in the same location, especially in elderly patients, is a warning sign that requires urgent evaluation, although this is mentioned in Praxis Medical Insights, a similar warning is given by the American Academy of Ophthalmology, thus the latter is preferred 2

Melanoma can spread to other adnexal structures and metastasize, potentially threatening life, as stated by the American Academy of Ophthalmology 1