[Somatosensory evoked potentials of the trigeminal nerve in chronic trichloroethylene poisoning]

Industrial intoxication by trichloroethylene can produce neurological disturbance of the trigeminal nerve. Therefore, among 105 workers exposed to this toxin, we recorded cortical responses after stimulation of the trigeminal nerve (TSEP) and we compared our results with a control group of 52 subjects. We considered the physical examination exploring, the facial sensitivity and reflexes, the levels of urinary metabolites of trichloroethylene and TSEP. We can describe 4 groups of workers: group A, 13 subjects with perturbations of clinical and evoked responses; group B, 27 subjects with normal physical examination though with disturbed TSEP; group C, 6 subjects had an abnormal examination though evoked responses were normal; group D, 59 subjects had normal clinical examination and TSEP. Disturbed TSEP (particularly delayed responses) are found among the older workers with the longest duration of exposure and higher level of exposure. The alteration of TSEP may appear before clinical disturbance. TSEP could represent a useful test for the supervision of the exposed workers and the clinical diagnosis of the trigeminal impairment.