Variations in corneal sensitivity with hydrogel contact lenses.

Changes in corneal sensitivity were studied in two groups of healthy subjects who wore hydrogel contact lenses: 44 persons whose lenses contained 38% water, and 23 who wore lenses of 55% water content. Corneal sensitivity decreased in both groups during the first 8 h following insertion; the decrease was more marked in the group who wore 38% water lenses. Changes in corneal tactile sensitivity were greater in women than in men, and determinations in different corneal zones showed that the central zone was less affected in sensitivity than any of the peripheral zones. After lenses were removed, tactile sensitivity showed full recovery within 4 h.