Effect of Fenestrating Soft Contact Lenses on Corneal Oxygen Availability

Recent clinical and experimental evidence suggests that a better physiological response to hydrogel lens wear can be obtained with fenestrations. To determine whether those observations could be attributed to increased comeal oxygenation, the equivalent oxygen percentage (EOP) was measured at the cornea of eight subjects wearing hydrogel contact lenses which had multiple fenestrations of 0.8 and 1.8 mm. It was possible to increase the mean EOP by 1.7 ± 1.3% O 2 (p < 0.002) beneath a standard thickness lens using four 1.8‐mm fenestrations. However, such lenses were uncomfortable to wear. Fenestrations that provided comfortable wear (0.8‐mm diameter) did not significantly increase the EOP beneath standard thickness lenses (–0.1 ± 1.0% O 2 , p > 0.1 for four fenestrations, and +0.2 ± 1.2% O 2 , p > 0.1 for eight fenestrations) or ultrathin lenses (–0.1 ± 1.3% O 2 , p > 0.1 for four fenestrations). It is concluded that fenestrations do not provide a clinically efficient means of in‐creasing the oxygen tension beneath hydrogel contact lenses.