These studies indicate that cell repopulation of alkali-burned rabbit corneas depends on vascularization. The extent of vascularization is a good gauge as to whether the cornea will maintain its integrity and how well it will heal. Vascularization and, therefore, revitalization are delayed when the alkali burn extends beyond the limbus, thus causing greater corneal destruction. Consequently, alkali burns which extend beyond the cornea should be given a more guarded prognosis.