Unilateral Battery Depletion in Parkinson’s Disease Patients Treated with Bilateral Subthalamic Nucleus Deep Brain Stimulation May Require Urgent Surgical Replacement

Complications of Deep Brain Stimulation for Movement Disorders: Literature Review and Personal Experience

The contemporary technique of deep brain stimulation (DBS) is very effective for management of movement disorders-including Parkinson's disease, generalized dystonia, and tremors-and has also been successfully applied for novel indications (e.g., intractable epilepsy and chronic pain). As a result, growing numbers of DBS procedures have been performed worldwide; correspondingly, the incidence of associated morbidity has also increased. All complications of DBS can be divided into those associated with (1) the surgical procedure, (2) the device itself, and (3) the applied electrical stimulation. On the basis of an analysis of the available literature and the personal experience of the author, it may be concluded that implantation of a DBS device is a relatively safe procedure accompanied by very low risks of major morbidity or a permanent neurological deficit. Nevertheless, awareness of the possible complications and application of appropriate preventive measures for their avoidance are very important for providing safe and effective treatment.

Deep Brain Stimulation in Parkinson's Disease

Deep brain stimulation (DBS) has become an established therapeutic tool for treating patients with Parkinson's disease (PD) who have troublesome motor fluctuations and dyskinesias refractory to best medical therapy. In addition to its proven efficacy in patients with late PD, the EARLYSTIM trial not only demonstrated the efficacy of DBS in patients with early motor complications but also showed that it did not lose its therapeutic efficacy as the years passed by. However, like all other therapies for PD, DBS is not offered to patients either as a cure for this disease nor is it expected to stop the progression of the neurodegenerative process underlying PD; these important issues need to be highlighted to patients who are considering this therapy. This article aims to provide an introduction to residents or trainees starting a career in movement disorders of the technical aspects of this therapy and the evidence base for its use. For the latter objective, PUBMED was searched from 1946 to 2017 combining the search terms "deep brain stimulation" and "Parkinson's disease" looking for studies demonstrating the efficacy of this therapy in PD. Inclusion criteria included studies that involved more than 20 patients with a physician confirmed diagnosis of PD and a follow-up of greater than or equal to at least 12 months. The findings from those studies on motor symptoms, medication requirements, quality of life, and independence in activities of daily living in PD patients are summarized and presented in tabulated form in this paper at the end.

Neurological Worsening After Implantable Pulse Generator Replacement

BACKGROUND

Most of the implantable pulse generators (IPGs) in deep brain stimulation (DBS) used to date are non-rechargeable requiring regular replacements. IPG replacement is a minor surgical procedure, but adverse events including neurological worsening have been reported. In this study, we determine the possibility of neurological worsening after IPG replacement in Parkinson's disease (PD) cases on chronic DBS therapy (CDT) and its electrophysiological basis along with the therapeutic interventions used to alleviate them.

METHODS

This study is a retrospective chart review of PD cases on CDT followed at London Movement Disorders Centre from January 2010 to December 2016. Included cases were those who underwent one or more IPG replacement.

RESULTS

A total of 45 PD cases on CDT underwent 62 IPG replacements involving 121 channels. Neurological worsening was observed in 16 (35.5%) cases following 17 (27.4%) IPG replacements, all following dual-channel IPG replacements. Tremor (41.2%), speech (35.3%), and gait (23.5%) worsened most commonly. Deviation from the pre-replacement parameters including voltage and impedance resulting in change in total electrical energy delivered (TEED) was the most common electrophysiological correlate, observed in 82.4% (14/17) IPGs having neurological worsening. This included switched laterality in a dual-channel IPG. Neurological worsening in the remaining 17.6% cases was hardware-related.

CONCLUSION

Neurological worsening followed 27.4% of IPG replacements in PD cases on CDT with approximately 82.4% of these being avoidable by carefully monitoring stimulation parameters to match pre-replacement TEED values.

Continuous perioperative apomorphine in deep brain stimulation surgery for Parkinson's disease

BACKGROUND

Patients with Parkinson's disease (PD) deprived of dopaminergic medication to facilitate awake testing during the deep brain stimulation (DBS) procedure are at increased risk of neurologic deterioration.. The aim of this survey was to demonstrate the safety of subcutaneous apomorphine treatment for reducing surgery-related neurologic deterioration in patients undergoing DBS surgery for PD.

METHODS

Ninety-two patients who underwent DBS surgery for PD between 11/2007 and 10/2011 in our department were retrospectively analyzed for this survey. Demographic data, apomorphine dosage, side-effects and need of ICU/IMC stay were collected and analyzed.

RESULTS

Seventy-two out of 92 patients (78.3%) received apomorphine treatment; main reason for omission of treatment was intolerable nausea (16/92, 17.3%). Apomorphine treatment was well tolerated and the most common side effect was nodular panniculitis. No severe complications were observed. No patient required ICU/IMC stay related to dopaminergic deprivation.

CONCLUSIONS

Perioperative withdrawal of dopaminergic medication in PD patients leads to an increased risk of neurologic and respiratory deterioration during DBS procedures. These complications can likely be tempered using perioperative subcutaneous apomorphine as a substitute. Our 5-year experience indicates a reduction in postoperative neurologic deterioration and ICU/IMC stay need. We consider perioperative apomorphine safe during DBS surgery for PD.

Battery life following pallidal deep brain stimulation (DBS) in children and young people with severe primary and secondary dystonia

BACKGROUND

The finite life of non-rechargeable batteries powering implantable pulse generators (IPG) necessitates their periodic replacement. Children receiving deep brain stimulation (DBS) may require frequent battery changes over their treatment lifetime.

OBJECTIVES

We aimed to determine the battery life of IPGs used in pallidal DBS for the treatment of dystonia in children and young people.

METHODS

We make use of a review of case notes of all children and young people undergoing DBS surgery at our institution from June 2005 to May 2010.

RESULTS

A total of 54 children and young people underwent surgery on at least one occasion, with a total of 76 IPGs implanted. Replacement IPGs due to battery failure were required in 15 out of 54 (27.8%). The average time to battery failure was 24.5 ± 2.9 months (95% confidence interval), with a range of 13-39 months. Battery life was significantly longer in primary compared to subsequent IPGs. No difference in longevity was seen between different IPG devices.

CONCLUSIONS

IPG battery life may be short in children and young people receiving treatment for dystonia. These findings highlight the potential benefits of the recently introduced rechargeable neurostimulators.

Placement of the Internal Pulse Generator for Deep Brain Stimulation in the Upper Back to Prevent Fracture of the Extension Wire due to Generator Rotation: Case Report

Deep brain stimulation (DBS) is a common surgical procedure used for the treatment of Parkinson's disease (PD) and essential tremor. A potential complication of this procedure is hardware failure. The authors report a case of DBS hardware failure in which repeated fractures of the extension wire were caused by abnormal rotational movements of the IPG placed in the loose subclavicular tissue of an overweight female. Implantation of the IPG in the suprascapular area prevented further extension wire fractures. This strategy may be especially relevant in overweight females with loose subclavicular tissue.

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

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.