Oxygen transmissibility of disposable hydrogel contact lenses.

We measured the central and mid-peripheral thicknesses of three "disposable" hydrogel contact lens designs of varying powers. These measurements allowed calculation of the areal average lens thicknesses (over a central 6 mm chord), which in turn allowed calculation of predicted oxygen transmissibility (Dk/L) for the lenses studied (using previously reported values for measured oxygen permeability [Dk] of these materials). Dk/L values for the disposable hydrogel lenses tested were found to range from 9 to 17 x 10(-9) cm mL O2/sec mL mmHg.