Psychosis and depressive disorder after deep brain stimulation of subthalamic nucleus in a patient with Parkinson disease: a case report.

Introduction. Deep brain stimulation (DBS) of subthalamic nucleus (STN) is widely accepted treatment of Parkinson's disease (PD) patients. It has been reported that PD patients undergoing STNDBS procedure are at elevated risk to experience wide range of mental disorders that include delirium and other psychotic disorders, mood disorders, anxiety disorders and neurocognitive disorders. Here we present a case of PD patient who developed psychiatric complications following bilateral STN-DBS implantation. Case report. A 72-year old male patient with a 12-year history of PD was referred for bilateral STN-DBS implantation procedure. The patient had no past history of mental disorders and was physically healthy based on standard clinical and laboratory investigations. On preoperative Magnetic Resonance Imaging neither the STN nor red nucleus were reliably visible. Therefore, it was decided to implant bilateral STN leads according to anterior commissure -- posterior commissure indirect targeting method and with intraoperative microstimulation and macro-stimulation of STN. The procedure was uneventful. However, next day after the procedure the patient developed typical delirium symptoms, which resolved during the next few days. However, a few weeks after the procedure the patient developed acute psychosis with visual hallucinations, delusions of persecution and reference, severe anxiety symptoms, psychomotoric agitation and disorganized speech. After one month inpatient treatment of psychosis, the patient developed depressive disorder with symptoms of apathy and cognitive decline. The patient was discharged home on psychiatric treatment that included antipsychotic and antidepressant medication and his DBS stimulation was switched to monopolar bilateral stimulation. During treatment his psychosis symptoms remitted but the patients developed moderate severity depressive symptoms, which started to regress after switching to bipolar STN stimulation. [ABSTRACT FROM AUTHOR]