Pigmentation of plica and lacrymal caruncle. Prevalence among Caucasians, Eskimos, and Japanese.

Consecutive screenings by the same examiner (the author) disclosed among 380 white North Europeans (Copenhagen, Denmark) pigmentation of the plica semilunaris and/or lacrymal caruncle in 2%, among 189 Mongols (Kyoto, Japan) in 4%, and among 257 Eskimos (East Greenland) in 45% (P less than 0.001). In Eskimos the phenomenon was found to be bilateral in 60% and confluent with pigmentation of the bulbar conjunctiva in 18%. The prevalence is the highest among males, rising with increasing age. It is correlated to the prevalence of pigmentation of the bulbar conjunctiva, whereas not to that of subconjunctival pigmentation round scleral emissaries.