Stimulations to basal ganglia and the efficiency of microminiaturized electrode recording (MER) to quantify STN neurons with deep brain stimulator (DBS)— the lead point in parkinson diseased conditions

Deep brain stimulation (DBS) of bilateral subthalamic nuclei (STN) is an efficient method of rehabilitation in subjects with advanced idiopathic Parkinson disease (PD). Accurate targeting of STN neurons and placement of microelectrodes are paramount importance for optimal results after STN-DBS. Stereo tactic assessment, intra-operative microelectrode recording and intra-operative stimulation effects have all been used in targeting, albeit the individual role of each modality is still not known. Microelectrode recordings of STN were detected in a mean of 3.5 ±1.1 channels on right hemisphere and 3.6 ±1.04 on left hemisphere.. Final channel selected were most commonly central seen in 42.3% followed by anterior in 33.7%. Concordance of final tract with the channel having the highest recording was 58.7%, with the channel showing maximum depth of recording was 48% and with either was 64%. Absence of any recording in the final tract chosen was seen in 6.52%, in these subjects the tract was chosen based on stimulation results. The depths of microelectrodes were detected by microelectrode recording in 75.6%. Microelectrode recording is useful to identify and confirm the tract in which DBS electrodes are placed and is most useful in determining the depth of electrodes placement but has to be taken in consideration with effects seen on macrostimulation.