Spheroid degeneration of cornea and conjunctiva. Prevalence among Eskimos in Greenland and Caucasians in Copenhagen.

The incidence of spheroid degeneration has been studied in a series of 659 Eskimos from Arctic South-West Greenland and one of 810 Caucasians in Copenhagen with its temperate climate. The over-all prevalence was highest among the Eskimos (12.3% against 4.1% among the Copenhageners, P less than 0.001). The prevalence was found to be independent of sex, but to rise with increasing age (however, with a fall again after the age of 70 years in Copenhagen). The spheroid deposits were present on the conjunctiva in 74%, on the cornea in 18%, and at both sites in 8%. 71% of the subjects displayed autofluorescent globular deposits. These constituted 10% of the total number of globules. The number of globules per subject averaged 30. Spheroid degeneration was rarely found temporally in Eskimos. Spheroid degenerative processes are most frequently seen in pingueculae, but are not considered bear any relation to pterygium.