High oxygen (O2) consuming organs such as the brain and the heart are easily affected by carbon monoxide (CO) intoxication. The most frequent changes are bilateral ischemic lesions and necrosis in the grey substance of brain tissue, particularly in the globus pallidus. Depending on the severity of intoxication, cerebral and cardiac findings may occur as well as visual impairment, although rare. Visual disorders may develop in patients recovering from coma. In this case report, we present a case with severe loss of vision consequent to CO intoxication, who demonstrated a complete response to long-term hyperbaric oxygen treatment.