Application of current steering with MICC directional lead in STN-DBS for Parkinson’s disease

BackgroundDeep brain stimulation (DBS) of the subthalamic nucleus (STN) has been widely performed for medically refractory Parkinson's disease (PD). Recent new technology of the multiple independent current control (MICC) with the directional lead provides both vertical and horizontal current steering on purposes. Consequently, MICC directional lead allows fine stimulation adjustment tailoring the condition of the individual patient. It is also expected to avoid stimulation induced adverse effects.MethodsWe retrospectively investigated the situation of current steering and the reason for doing so 3-month and 1-year after surgery in 80 patients who underwent bilateral STN-DBS for PD using MICC directional lead.ResultsIn 160 leads of 80 patients, current steering was used in 39 leads (24%) 3-month after surgery, but in 80 leads (50%) 1-year after surgery. As for the reason, vertical steering was used in 7 leads (4%) and horizontal steering was used in 28 leads (18%) to explore better stimulation effect for cardinal symptoms of PD. In addition, vertical steering was used for improving dyskinesia in 40 leads (25%) and alleviating tremor in 5 leads (3%). Horizontal steering was also used for avoiding adverse effects in 15 leads (9%), most of which were used to alleviate the symptoms of excessive stimulation of pyramidal tract.ConclusionsCurrent steering with the MICC directional lead was actually utilized in STN-DBS to explore more precise control of motor symptoms and also useful to avoid stimulation-induced adverse effect. Current steering is especially used in the later period after introduction of DBS.