Trans-cranial Doppler and peripheral sensory threshold tests for carbon disulfide poisoning

Abstract

Trans-cranial doppler (TCD) and sensory threshold (vibration, pain and discrimination) tests, which are safe and inexpensive techniques, were applied to detect cerebral vasoreactivity or neuropathic changes between carbon disulfide (CS2) poisoning cases and two control groups respectively. The cases were 31 male CS2 poisoning workers, and the first control group for the TCD test consisted of eight healthy men, and the second group for the threshold test were 21 healthy male workers. In the TCD test, the blood flow velocity in both middle cerebral arteries and the CO2 content of expired air were measured to evaluate CO2 reactivity. The vibration and pain perception threshold were measured on both the 2nd and 5th fingers. The CS2 poisoning cases showed higher rates of abnormal CO2 reactivity above the cut-off value than healthy controls (80.0-81.8% vs 0%). Among the threshold tests, the proportions of abnormal pain threshold of both the 2nd and 5th fingers were higher in poisoning cases than in the controls (77.8%-88.9% vs 11.1-33.3%) among over 45 yr old subjects. CO2 reactivity and pain threshold test showed the possibility to defect changes in cerebral vessels and the sensory threshold in CS2 exposure cases, but there should be further study to apply these tests to workers exposed to CS2 before the development of CS2 poisoning, with large number of control subjects.