A case of cortical blindness due to carbon monoxide poisoning

We report a case of cortical blindness occurring 7 days after acute CO poisoning with no other neurological or psychic deficits apart from denial of the blindness with visual confabulation and slight loss of retentive memory. There was scant correlation between the course of the clinical pattern, which cleared completely within 6 days, and the electroencephalographic pattern with marked and diffuse slowing, which did not recede completely during 3 months observation. CT scanning of the skull, initially within normal limits, displayed 2 weeks later a faint but diffuse hypodensity of the white substance, more marked in the occipital region, which was no longer present 80 days after the first scan.