"Twiddler syndrome" in two patients with deep brain stimulation.

Twiddler syndrome occurs when a patient intentionally or unintentionally manipulates an implantable generator (usually a pacemaker) and dislodges the pacing leads, causing malfunction of the device. Though the syndrome has been described in patients with pacemakers, to our knowledge only one spontaneous case has been described in patients undergoing deep brain stimulation for movement disorders. We report the clinical cases of two patients with Parkinson's disease who had subthalamic bilateral electrodes implanted and presented the twiddler syndrome 2 and 3 years after surgery. We analysed the possible mechanisms of this syndrome and note that twiddler syndrome should be suspected in patients undergoing deep brain stimulation and showing hardware dysfunction.