We studied the macrostructural characteristics of papillary changes of the upper tarsal conjunctiva associated with the wearing of polymethyl methacrylate (PMMA) contact lenses. Fifty subjects with elevated conjunctival papillae greater than 0.3 mm in diameter were studied. Macrostructural characteristics recorded were location, diameter, and number of papillae, presence or absence of staining at the apices of papillae, and degree of hyperemia of the upper tarsal conjunctiva. Patient information collected included age, duration of lens wear, average daily lens wearing time, presence or absence of itching or mucus, refractive status, and atopic history. The tarsal conjunctiva was divided into three zones of equal size. Papillae were present in various zones and combinations of zones; however, papillae were never confined exclusively to either (1) the zone adjacent to the tarsal folds or (2) the latter zone in combination with the zone adjacent to the eyelid margin without also occurring in the intervening zone. The diameter of the papillae ranged from greater than 0.3 mm to 2.0 mm. The number of papillae per eyelid ranged from two to over 100. The apices of the papillae were frequently flattened and craterlike, and often stained with fluorescein.