Stability of symptom control after replacement of impulse generators for deep brain stimulation

Abstract

Object Impulse generators (IPGs) for deep brain stimulation (DBS) need to be replaced when their internal batteries fail or when technical problems occur. New IPGs are routinely programmed with the previous stimulation parameters. In this study, the authors evaluate the stability of symptom control after such IPG replacements. Methods The authors retrospectively analyzed the outcome of 56 IPG replacements in 42 patients with various movement disorders treated using DBS. Results Stable symptom control was found in 65% of single-channel IPG replacements and 53% of dual-channel IPG replacements. Worsening of symptoms resulted primarily from changes in stimulation effects requiring reprogramming of stimulation parameters (17% of dual-channel IPG and 25% of single-channel IPG). In 14% of dualchannel IPG replacements, instability resulted from erroneous extension adjustment with change in laterality. A new short circuit of active with previously inactive contacts of the quadripolar stimulation lead resulted in a worsening of symptoms in 4% of replacements. Conclusions Replacement of the IPG requires careful follow-up of patients with DBS to ensure stable symptom control.