Deep brain stimulation for the treatment of obsessive-compulsive disorder.

Obsessive-compulsive disorder (OCD) is a chronic psychiatric condition characterized by invasive thoughts, repetitive compulsions, ritualistic behaviours and intense anxiety. Based on the efficacy of anterior capsulotomy for OCD, high-frequency deep brain stimulation (DBS) of the same target was expected to improve OCD by producing a functional and reversible lesion. Subsequently, with growing functional data regarding the neuroanatomical correlates of OCD, other targets within the orbitofronto-striato-thalamo-cortical (CSTC) network were explored. Following the first positive results of DBS in the original anterior capsule target (anterior limb of the internal capsule), targeting shifted more towards the ventral capsule/ventral striatum and nucleus accumbens. The subthalamic nucleus (STN) was tried after positive results on obsessive-compulsive symptoms from STN DBS in patients with Parkinson's disease and comorbid OCD. The chapter also discusses DBS in other nodes of CSTC network, that is, the inferior thalamic peduncle or globus pallidus interna.