Case report: myopic shift in a stable corneal graft following high altitude exposure.

Refractive changes in patients after radial keratotomy who are exposed to high altitudes have been reported previously. Hypoxic environments may cause corneal curvature changes in surgically altered corneas that result in refractive error shifts. We report a patient who experienced a partially reversible myopic shift in a previously stable corneal transplant after prolonged exposure to high altitude.