RESUMO
Superficial corneal foreign bodies (FBs) are a common occupational ocular hazard and can cause visually important astigmatism. A 23-year-old male working in a factory, which produced dry ice (solid carbon dioxide), presented to our emergency unit with symptoms of whitish discolouration of the right cornea for 1 day. Visual acuity in both eyes was 20/20 and slit-lamp examination of the right eye revealed an irregularly shaped whitish superficial FB in the inferior paracentral cornea with surrounding superior nebular opacity. Its gentle removal with a moistened cotton bud revealed an underlying epithelial defect with residual whitish changes. At 1-month of follow-up, the patient had nebulo-macular corneal opacity with stromal thinning at the site of impacted dry ice. We speculate that dry ice causes corneal damage due to its extremely cold temperatures and the formation of carbonic acid.
