Treating CS gas injuries to the eye

Treating CS gas injuries to the eye Exposure at close range is particularly dangerous EDr1OR,-Jean-Paul Yih's editorial on injuries to the eye caused by O-chlorobenzylidene malono- nitrile (CS) gas, or tear gas, draws attention to the short term effects of the gas on the eye and suggests that such injuries may well be a future problem as individual police officers in Britain will soon be carrying pocket aerosols of CS gas.' Yih implies that the ocular toxicity of CS gas is rapidly reversible; however, the ocular irritation from 1-chloroacetophenone (another tear gas agent) typically lasts only 15 minutes but may persist for up to three days.2The problems are particularly pronounced when the charge of tear gas is fired at close range: powder infiltration of the conjunctiva, cornea, and sclera will occur.The forces are so great that conjunctival tearing may occur.Corneal stromal oedema and later deep vascularisation may ensue, and a multitude of complications have been reported, including symblepharon, pseudopterygium, infective keratitis, trophic ketatopathy, posterior synechia, secondary glaucoma, cataracts, hyphaema, vitreous haemor- rhage, and traumatic optic neuropathy.' Thus