INTRAOCULAR MOTILITY, ELECTROPHYSIOLOGICAL TESTS AND VISUAL-FIELDS INDRUG-ADDICTS

The effects of drugs on intraocular motility, retina function and cent ral pathways in a drug addicts population have been studied. The study group were made up of 15 drug addicts. Fifteen healthy subjects who h ad never used drugs acted as a control group. Refractive state, accomm odation, tonometry, assessment of pupillary reflexes, campimetry, visu al evoked cortical potential (VECP) and ERG were performed in all case s. All the subjects studied used heroine, 12 used cannabis and 12 used cocaine. Refraction was normal in all cases. Accommodation amplitude in normal subjects ranged from 8.5 to 11.5 D, and from 3.5 to 9.5 D in the drug addicts group. Tonometry indicated a tendency to lower intra ocular pressure values. Direct and consensual pupillary reflexes were normal in eight subjects, but were sluggish in the rest. Campimetry sh owed relative and absolute scotoma in five subjects. VECP were found t o be normal in two of the cases, moderately pathological in six and pa thological in the remaining seven cases. As for the ERG, it showed non -specific altered traces in 11 cases. Accommodation amplitude was lowe r than normal in 20 eyes. The decrease of VECP with altered traces but with an increase of latency, seem to indicate the presence of an alte ration in the optical pathway or in the cortical centres. The findings in ERG point out a decrease of amplitudes and an increase of latency in more than half the population studied.