What Researchers Did
Researchers investigated how contact lens wear causes corneal acidosis by examining the roles of oxygen deprivation (hypoxia) and carbon dioxide buildup (hypercapnia) in a hyperbaric oxygen environment.
What They Found
In a study of seven subjects wearing hydrogel lenses, researchers exposed one eye to air and the other to 80% oxygen. After 80 minutes, four of five subjects wearing low oxygen transmissibility lenses under hyperbaric conditions showed a pH drop of 0.23 +/- 0.05, with no corneal swelling, indicating hypercapnia alone caused acidosis. In contrast, the same lens with air exposure led to a larger pH drop of 0.62 +/- 0.48 and corneal swelling, suggesting both hypoxia and hypercapnia contributed.
Canadian Relevance
No direct Canadian connection identified.
Study Limitations
This was a preliminary study with a small number of participants, limiting the generalizability of the findings.