Neurospect in neurotoxic chemical exposure demonstration of long-term functional abnormalities

Patients who had experienced well-documented neurotoxic exposure months or years earlier were evaluated. Seventy-two right-handed adults who claimed continuing abnormalities of cognitive and memory function were examined after Xenon-133 inhalation and i.v. HMPAO. Single photon emission computed tomography (SPECT) results were statistically compared with age-matched controls. Bilateral, often asymmetrical, impairment of perfusion was found, mostly in the frontal, temporal, and parietal lobes. This hypoperfusion was predominantly left-sided in young patients and predominantly right-sided in the elderly. Abnormalities were found months and years after neurotoxic exposure had ceased. Our findings suggest that NeuroSPECT can provide evidence of impaired cerebral function and may therefore help to further define neurotoxic exposure and its chronic effects.