[Hypoxic brain damage after carbon monoxide poisoning. Visual agnosia, reduced initiative and memory and delayed sequelae].

Four patients with hypoxic brain damage caused by carbon monoxide poisoning are described. Three of these had attempted suicide with car exhaust fumes. Two patients had visual agnosia due to lesions in the parieto-occipital cortex. Three patients had temporary Parkinsonian symptoms. In two of these patients CT and MRI showed lesions in the globus pallidus. They also showed reduced initiative, and in one patient this was combined with minor tics and obsessive symptoms. One patient had impaired memory as the only symptom. The patient with the longest lasting exposure developed delayed sequelae; three weeks after the poisoning he became apathetic and confused, with failing memory, Parkinsonian symptoms, and urinary and faecal incontinence. MRI showed demyelination in the periventricular white matter. His condition started to improve two months after the accident.