Effect of epithelial cell injury on anterior corneal oxygen flux.

The aerobic response of epithelial metabolism to cellular injury or disease was studied with a three-layer model of the cornea. Nonclassical (Michaelis-Menten) respiratory kinetics were assumed, and predicted fluxes validated by reference to known estimates. The model indicates that epithelial oxygen flux is linearly related to epithelial oxygen consumption, and is therefore a direct index of epithelial aerobic metabolism. Injury leading to de-epithelialization decreases total anterior corneal oxygen flux. The decreases reported experimentally with a polarographic oxygen sensor on the denuded stroma in vivo are greater than theoretically predicted. This effect is due to a limited capture depth of the technique, which "sees" only the anterior stroma.