EFFECTS OF CHRONIC LITHIUM TREATMENT ON RETINAL ELECTROPHYSIOLOGIC FUNCTION

Some hypotheses suggest that lithium produces its therapeutic effect b y reducing sensitivity to light at the level of the retina. In humans, acute administration of lithium is associated with a reduction in ret inal light sensitivity, To determine whether similar retinal light sen sitivity changes occur with chronic use, we studied 24 euthymic bipola r patients on chronic lithium treatment and 21 age- and sex-matched no rmal comparison subjects using electroretinography (ERG) and electro-o culography (EGG), No significant differences were found in ERG b-wave amplitudes or implicit times, or in EOG ratios, between the two groups , We conclude that chronic lithium use is not associated with differen ces in retinal light sensitivity when bipolar patients are compared to normal comparison subjects, and that there is no evidence for retinal toxicity with long-term lithium treatment. (C) 1997 by R.W. Lam et al .