Scleral contact lenses and hypoxia

The very first contact lenses were scleral contact lens designs made from glass and later from plastic materials [ [1] Pearson R.M. Comments on “Modern scleral contact lenses: a review.” Letter to the Editor. Contact Lens Ant Eye. 2015; 38: 73-74 Abstract Full Text Full Text PDF PubMed Scopus (2) Google Scholar ], both of which are gas-impermeable and created an anoxic environment to the eye, severely limiting their wearing time and clinical utility. The introduction of the gas permeable rigid lens material almost a century after the first documented scleral contact lens fits set the scene for the renaissance of this device [ [2] Ezekiel D. Gas permeable haptic lenses. J Br Contact Lens Assoc. 1983; 6: 158-161 Abstract Full Text PDF Scopus (90) Google Scholar ]. Three decades later scleral contact lenses are manufactured in high Dk material – 100 or higher – using computer operated lathes to control overall lens thickness and cut complex curves. However the question of corneal oxygenation appears to remain incompletely resolved. Has the modern scleral lens design cut in a high Dk material completely eliminated hypoxic ocular effects?