Spheroid degeneration, pinguecula, and pterygium among Arabs in the Red Sea territory, Jordan.

Report of an examination of 127 Arabs in the Red Sea City of Aqaba, Jordan. The results are compared with those of the author's examinations, using a similar apparatus, of 659 Eskimos in Western Greenland and 810 Caucasians in Copenhagen. Ultraviolet (u.v.) light is at a maximum in the Red Sea territory, considerable in Greenland, and negligible in Copenhagen. The prevalences of the following degenerative processes are high at the Red Sea, somewhat lower in Greenland, and low in Copenhagen: Climato-keratopathy gr. III (across the cornea, often with autofluorescent spheroids, always with conjunctival location as well), conjunctival spheroids (39%), and pinguecula (90% at the Red Sea). The prevalence of the conjunctival spheroid degeneration greatly exceeds that of the corneal. No difference is demonstrable between tropical and arctic keratopathy. The investigations performed gave results bearing out the view that u.v. light is responsible for all the above degenerative processes. Pterygium is equally frequent at the Red Sea and in Greenland. Lipid deposits (6%) and scleral plaques are not more prevalent at the Red Sea, a fact which argues against an ultraviolet genesis.