Term for contact lenses or contact lens materials with Dk/t > 85 x 10-9 (cm x ml O2)/(s x ml x mmHg). Also see Dk, Dk/t, Oxygen demand and Oxygen supply.
Reduced oxygenation of the corneal tissue causing a variety of problems. The severity of the consequences depends on the level and duration of hypoxia. Common signs of hypoxia are corneal vascularization, corneal oedema and microcysts. Any signs of hypoxia should be immediately addressed. In some cases temporary or permanent discontinuation of lens wear is necessary to prevent further damage. High Dk contact lenses should be fitted to avoid hypoxic stress or to improve oxygen supply.