1. Blood pigment

 *A. After subconjunctival hemorrhage-red or later fine brown spots
 B. Yellow tinge of malaria, blackwater fever, or yellow fever
 C. Pigmentary limbal ring associated with senile, traumatic, or diseased conditions

2. Bile pigments (yellow)-obstructive or hemorrhagic jaundice
3. Melanin pigmentation 

 A. Acanthosis nigricans
 *B. Addison disease (adrenal cortical insufficiency)
 C. Alcaptonuric ochronosis
 D. Chlorpromazine (Thorazine)
 E. Endogenous ochronosis
 F. Keratomalacia
 G. Trachoma
 *H. Use of epinephrine or epinephrine bitartrate, borate, and hydrochloride
 I. Vernal conjunctivitis
 J. Vitiligo (leukoderma)-increased conjunctival pigmentation
 K. Xeroderma pigmentosum

4. Drugs, including the following:

acid bismuth sodium     tartrate Alcian blue amiodarone amodiaquine amphotericin B antimony lithium     thiomalate antimony potassium     tartrate antimony sodium     tartrate antimony sodium     thioglycollate antipyrine bismuth carbonate(?) bismuth oxychloride(?) bismuth salicylate(?) bismuth sodium tartrate bismuth sodium      thioglycollate (?) bismuth sodium     triglycollamate(?)

bismuth subcarbonate bismuth subsalicylate captopril chloroquine chlortetracycline chrysarobin clofazimine colloidal silver demeclocycline diethazine doxycycline enalapril ethopropazine ferrocholinate ferrous fumarate ferrous gluconate ferrous succinate ferrous sulfate fluorescein gold AU 198 gold sodium thiomalate gold sodium thiosulfate hydroxychloroquine

iron dextran iron sorbitol ketoprofen methacycline methylene blue minocycline minoxidil oxytetracycline penicillamine polysaccharide iron      complex quinacrine rifabutin rifampin silver nitrate     silver protein rose bengal sodium     antimonylgluconate stibocaptate stibophen tetracycline trypan blue vitamin A

5. Foreign substances such as silver (argyrosis), iron (siderosis), copper (chalcosis), arsenic (arsenic melanosis), gold (chrysiasis), aluminum, quinones, aniline dyes, and eye cosmetics containing carbon black
*6. Benign melanosis-overactivity of melanocytes

 A. Epithelial-congenital or acquired, for example., following radiation or use of  chemicals (arsenic); in Addison disease; because of chronic conjunctivitis  (trachoma, vernal conjunctivitis, onchocerciasis, keratomalacia)
 B. Subepithelial-congenital or in association with melanosis oculi or nevus of Ota

7. Neoplasms

 *A. Nevus-most common in children, localized stationary, elevated, cystic, mayor may not have  pigmentation
 *B. Malignant melanoma arising from preexisting nevus, apparently normal  conjunctiva, or from an area of acquired pigmentation (intraepithelial melanoma);  occurs primarily in middle age; diffuse, flat, pigmentation; progressive; no cysts
 C. Secondary melanotic tumors
 D. Incidentally pigmented tumors, such as a melanocarcinoma
 E. Secondary metastatic tumors from lung or breast

8. Ocular causes, including the following:

 A. Apocrine adenocarcinomas
 B. Foreign bodies
 C. Hematic cysts
 D. Moll gland cystadenomas
 E. Staphylomas
 F. Subconjunctival hematomas

Cheskes J, et al. Ocular manifestations of alkaptonuric ochronosis. Arch Ophthalmol 2000; 118:724-727.

Fraunfelder FT, Fraunfelder FW. Drug-induced ocular side effects. Woburn, MA: Butterworth-Heinemann, 2001.

Linebarger EJ, et al. Conjunctival aluminum deposition following pneumatic cryopexy. Arch Ophthalmol 1999; 117:692.

Roy FH. Ocular syndromes and systemic diseases. 3rd ed. Philadelphia: Lippincott Williams & Wilkins, 2002.

Seregard S. Conjunctival melanoma. Surv Ophthalmol 1998; 42:32l-350.