Why do some old people have yellow eyes?

Yellow eyes: 1- jaundice: yellowing of the sclerae (whites of the eyes), resulting from bile (or its pigment bilirrubin). This indicates serious liver disease. 2-although not exactly yellow, the brown pigmentation of the eye may "spill" on the sclera or conjunctiva resulting in an almost yellow appearance. 3- i've seen pts calling "yellow" pingueculae (fleshy nodules in the conjunctiva, @ 3 & 9 o clock.