MRI, quantitative MRI, SPECT, and neuropsychological findings following carbon monoxide poisoning

Carbon monoxide (CO) poisoning has been shown to result in neuropathologic changes and cognitive impairments due to anoxia and other related biochemic al mechanisms. The present study investigated brain-behaviour relationships between neuropsychological outcome and SPECT, MRI, and Quantitative magnet ic resonance imaging (QMRI) in 21 patients with CO poisoning. Ninety-three per cent of the patients exhibited a variety of cognitive impairments, incl uding impaired attention, memory, executive function, and mental processing speed. Ninety-five per cent of the patients experienced affective changes including depression and anxiety. The results from the imaging studies reve aled that 38% of the patients had abnormal clinical MRI scans, 67% had abno rmal SPECT scans, and 67% had QMRI findings including hippocampal atrophy a nd/or diffuse cortical atrophy evidenced by an enlarged ventricle-to-brain ratio (VBI). Hippocampal atrophy was also found on QMRI. SPECT and QMRI app ear to be sensitive tools which can be used to identify the neuropathologic al changes and cerebral perfusion defects which occur following CO poisonin g. Cerebral perfusion defects include frontal and temporal lobe hypoperfusi on. Significant relationships existed between the various imaging technique s and neuropsychological impairments. The data from this study indicate tha t a multi-faceted approach to clinical evaluation of the neuropathological and neurobehavioural changes following CO poisoning may provide comprehensi ve information regarding the neuroanatomical and neurobehavioural effects o f CO poisoning.