Open AccessInvestigation of Deep Brain Stimulation Mechanisms During Implantable Pulse Generator Replacement Surgery
Author(s) -
Swan Brandon D.,
Grill Warren M.,
Turner Dennis A.
Publication year - 2014
Publication title -
neuromodulation: technology at the neural interface
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 1.296
H-Index - 60
eISSN - 1525-1403
pISSN - 1094-7159
DOI - 10.1111/ner.12123
Subject(s) - deep brain stimulation , medicine , stimulation , essential tremor , physical medicine and rehabilitation , movement disorders , dystonia , implant , parkinson's disease , surgery , anesthesia , disease , psychiatry
Background Direct testing of deep brain stimulation ( DBS ) mechanisms in humans is needed to assess therapy and to understand stimulation effects. Objective We developed an innovative paradigm for investigation of DBS on human movement disorders. Temporary connection to the DBS electrode during implantable pulse generator ( IPG ) replacement permitted analysis of novel patterns of stimulation on motor symptoms, which could enhance efficacy and improve battery life. Materials and Methods Patients enrolled in this prospective, I nstitutional R eview B oard‐approved study underwent IPG replacement using local (monitored) anesthesia. Following device explant, the DBS electrode was connected to an external, isolated electrical stimulator using a sterile adapter cable. Different temporal patterns of stimulation were delivered while quantifying upper‐extremity tremor (tri‐axial accelerometry) or bradykinesia (finger‐tapping). Upon experiment completion, the new IPG was implanted. Results Among 159 IPG replacements from 2005 to 2011, 56 patients agreed to the research study (16 essential tremor [ ET ], 31 Parkinson's disease [ PD ], 5 mixed ET / PD tremor, 3 multiple sclerosis, 1 tremor/myoclonus). Surgical procedures were extended by 42 ± 8.2 min in 37 patients completing the study. Motor symptoms varied with stimulation pattern, with some patterns showing improved tremor or bradykinesia control. No postoperative infections or complications were observed in the 159 patients. Conclusion IPG replacement occurs when the DBS /brain interface is stable and patients demonstrate symptom reduction with known stimulation parameters. Conducting research at this time point avoids DBS implant issues, including temporary microlesion effects, fluctuating electrode impedances, and technical limitations of contemporary IPGs , providing advantageous conditions to conduct translational DBS research with minimal additional risk to research subjects.