Authors : Venkateshwarla Rama Raju, Venkateshwarla Rama Raju
DOI : 10.18231/j.ijn.2020.057
Volume : 6
Issue : 4
Year : 2020
Page No : 301-316
Deep brain stimulation (DBS) is one effectual reliable method to reduce motor symptoms in subjects with neurodegenerative disorder of Parkinson’s disease (PD—Parkinson diseased conditions/patients). However, objective methods for quantifying its efficacy are lacking. Therefore, we present an investigative fusion study for quantifying the effects of DBS in PD by using the microelectrode recording system (MER) to measure the MER signal parameters such as amplitude, frequency, pulse-width, etc. We measured those parameters from the MER signals of subthalamic nuclei (STN) neurons of 46 subjects (92 sides of PD
conditions) with DBS stimulator.
The channel with maximum recording and the earliest recording were recorded on both sides. Intraoperative test stimulation was performed in all channels from the level at the onset of MER recording. Stimulation was done at 1mv, 3mv to assess the improvement in bradykinesia, rigidity and tremor. Appearance of dyskinesias was considered to be associated with accurate targeting. Side effects were assessed at 5mv and 7mv to ensure that the final channel chosen had maximum improvement with least side effects. Correlation was assessed between the aspects of MER and the final channel chosen in 46 subjects (92 sides, i.e., right and left hemispheres of the brain).
Clinical evaluation of subjects showed that their motor symptoms were effectively reduced with DBS. The analysis results showed that the signal characteristics of 46 PD subjects’ subthalamic nuclei (STN) neurons were heterogeneous with DBS on and off. These observations indicate that the DBS with MER technique can be used to objectively quantify the effects of DBS on the neuromuscular function of PD subjects. Further studies are suggested to estimate the clinical and/or diagnostic sensitivity of the method to different types of PD. The measurement parameters in combination of MER with DBS method in acute targeting can be used to quantify the effects of DBS objectively, cost-effectively and non-invasively.
Keywords: Deep brain stimulation (DBS).