Sulfur mustard-induced ocular injuries: Update on mechanisms and management

Sulfur mustard (SM; mustard gas) is a classic chemical warfare agent that has been used in several wars and is still a potential threat especially in the Middle-East region. Victims experience acute symptoms in airexposed organs including skin, respiratory tract and the eyes. Survivors of the acute stage might develop chronic or delayed-onset complications in the exposed organs. The exact mechanism(s) of SM-induced tissue damage is still unknown, however DNA alkylation and oxidative damage are the most relevant mechanisms. Eye is the most sensitive organ to the SM vapor and ocular symptoms usually precede other manifestations. Ocular findings including blepharitis, dry eye disease, corneal vascularization, persistent epithelial defects, limbal ischemia, limbal stem cell deficiency, corneal thinning, corneal opacity and corneal innervation abnormalities have been reported several years after SM exposure. In this review, mechanisms of acute and chronic/delayed ocular manifestations of SM and their current management and potential future therapies have been discussed. We have also included recent advances in amniotic membrane transplantation, cultivated stem cell transplantation and anti-angiogenic therapies which might be considered as therapeutic options in SM-induced ocular damage in the future.