An unusual presentation of convergence insufficiency in a patient with Parkinson's disease stimulated by deep brain stimulation.

Given the therapeutic effects of deep brain stimulation on convergence insufficiency reported in several studies, in addition to the influence of deep brain stimulation as Parkinson's Disease treatment in areas possibly associated with vergence control, convergence insufficiency secondary to deep brain stimulation does not seem very unlikely, although not often reported. Further studies are needed to optimize deep brain stimulation surgery to maximize benefits and limit adverse events, as well as being aware of convergence insufficiency as a possible cause for visual disturbance.