Corneal opacity of alkali-injured eye and injured eyes treated with H2 dissolved in PBS (H2) or with PBS free of H2 (buffer). Representative photographs show control healthy eye (a), alkali-injured eye (immediately after the injury) (b), the injured eye treated with H2 solution from day 2 to day 20 (c, d, e, f), and injured eye treated with buffer from day 2 to day 20 (g, h, i, j). Corneal transparency renewed only in corneas treated with H2 solution. Corneas treated with buffer remained opalescent and corneas were vascularized. Arrows point to vessels.