ABSTRACT
Data regarding the effect of deep brain stimulation (DBS) surgery on the dopamine dysregulation syndrome (DDS), impulse control disorders (ICDs) and punding in Parkinson's disease (PD) are limited. We present a case series of 21 operated PD patients who had exhibited DDS, ICDs or punding at some stage during the disease. DDS remained unimproved or worsened post-operatively in 12/17 patients with pre-operative DDS (71%) (nine bilateral subthalamic nucleus [STN], one right-sided STN, two bilateral globus pallidus internus [GPi] DBS). DDS improved or resolved after bilateral STN DBS in 5/17 patients with pre-operative DDS. DDS apparently developed for the first time after bilateral STN DBS in two patients, although only after a latency of eight years in one case. One patient without reported pre-operative DDS or ICDs developed pathological gambling post-STN DBS. One patient had pathological gambling which resolved pre-operatively, and did not recur post-DBS. Thus, DDS, ICDs and punding may persist, worsen or develop for the first time after DBS surgery, although a minority of patients improved dramatically. Predictive factors may include physician vigilance, motor outcome and patient compliance.
Subject(s)
Deep Brain Stimulation/adverse effects , Disruptive, Impulse Control, and Conduct Disorders/etiology , Disruptive, Impulse Control, and Conduct Disorders/psychology , Dopamine/physiology , Neurosurgical Procedures/adverse effects , Parkinson Disease/surgery , Postoperative Complications/psychology , Adolescent , Adult , Dopamine/metabolism , Female , Health Care Surveys , Humans , Magnetic Resonance Imaging , Male , Middle Aged , Movement Disorders/etiology , Movement Disorders/psychology , Parkinson Disease/complications , Parkinson Disease/psychology , Patient Compliance , Surveys and Questionnaires , Treatment Outcome , Young AdultABSTRACT
Although some motor functions of the basal ganglia have been well studied, the oculomotor functions are not well established. We studied eye movements in patients with Parkinson's disease (PD) undergoing pallidotomy to assess the role of the globus pallidus interna (GPi) in oculomotor control. Horizontal visually guided, gap and predictive saccades as well as ocular fixation were studied in patients with advanced PD before and 1 month after unilateral pallidotomy, and in healthy controls on two occasions 1 month apart. There was no difference in saccadic latency or accuracy, the number of saccadic anticipations or the ability to generate predictive saccades between the two assessments for either patients or controls. The number and amplitude of square wave jerks during ocular fixation however increased significantly in patients after pallidotomy. The results imply altered function of frontal or prefrontal cortical regions involved in ocular fixation resulting from a disruption to inhibitory pallidal influences on thalamocortical projections. The posteroventral GPi however appears not to be involved in externally controlled or predictive saccadic function.
