Effects of subthalamic nucleus stimulation on urodynamic findings in patients with Parkinson's disease

Autonomic failure: Clinicopathologic, physiologic, and genetic aspects

Over the past century, generations of neuroscientists, pathologists, and clinicians have elucidated the underlying causes of autonomic failure found in neurodegenerative, inherited, and antibody-mediated autoimmune disorders, each with pathognomonic clinicopathologic features. Autonomic failure affects central autonomic nervous system components in the α-synucleinopathy, multiple system atrophy, characterized clinically by levodopa-unresponsive parkinsonism or cerebellar ataxia, and pathologically by argyrophilic glial cytoplasmic inclusions (GCIs). Two other central neurodegenerative disorders, pure autonomic failure characterized clinically by deficits in norepinephrine synthesis and release from peripheral sympathetic nerve terminals; and Parkinson's disease, with early and widespread autonomic deficits independent of the loss of striatal dopamine terminals, both express Lewy pathology. The rare congenital disorder, hereditary sensory, and autonomic neuropathy type III (or Riley-Day, familial dysautonomia) causes life-threatening autonomic failure due to a genetic mutation that results in loss of functioning baroreceptors, effectively separating afferent mechanosensing neurons from the brain. Autoimmune autonomic ganglionopathy caused by autoantibodies targeting ganglionic α3-acetylcholine receptors instead presents with subacute isolated autonomic failure affecting sympathetic, parasympathetic, and enteric nervous system function in various combinations. This chapter is an overview of these major autonomic disorders with an emphasis on their historical background, neuropathological features, etiopathogenesis, diagnosis, and treatment.

New approaches to treatments for sleep, pain and autonomic failure in Parkinson's disease - Pharmacological therapies

Non-motor symptoms (NMSs) are highly prevalent throughout the course of Parkinson's disease (PD). Pain, autonomic dysfunction and sleep disturbances remain at the forefront of the most common NMSs; their treatment is challenging and their effect on the quality of life of both patients and caregivers detrimental. Yet, the landscape of clinical trials in PD is still dominated by therapeutic strategies seeking to ameliorate motor symptoms; subsequently, effective strategies to successfully treat NMSs remain a huge unmet need. Wider awareness among industry and researchers is thus essential to give rise to development and delivery of high-quality, large-scale clinical trials in enriched populations of patients with PD-related pain, autonomic dysfunction and sleep. In this review, we discuss recent developments in the field of pharmacological treatment strategies designed or re-purposed to target three key NMSs: pain, autonomic dysfunction and sleep disturbances. We focus on emerging evidence from recent clinical trials and outline some exciting and intriguing findings that call for further investigations.

Effect of Deep Brain Stimulation on Female Parkinsonian Patients with Lower Urinary Tract Symptoms

PURPOSE

This study aimed to investigate the characteristics of urodynamics in female parkinsonian patients with lower urinary tract symptoms (LUTS) and evaluate the outcomes of deep brain stimulation (DBS) based on overactive bladder (OAB) scores and quality of life (QOL) scores.

PATIENTS AND METHODS

Urodynamic assessment was performed in 20 female parkinsonian patients with LUTS. OAB scores and QOL scores were collected before and 6 months after DBS treatment (The target of DBS is STN). We evaluated the related factors affecting QOL score and also the changes in QOL score after DBS treatment.

RESULTS

The mean age of 20 patients was 60.6±6.3 years, with 65% of patients identified with OAB in urodynamic studies. The mean OAB total score and QOL score at baseline were 7.3±3.7 and 5.0±1.1, respectively. Four items in the OAB score were found to be independent factors and they influenced the baseline QOL scores. Six months after DBS treatment, the OAB total score and the QOL score were significantly decreased (3.7±3.2 (p = 0.002) and 3.4±1.4 (p < 0.001), respectively). Improvements in OAB item 2 (nocturia) and item 3 (urgency) scores were found to be independent factors, which had an influence on the improvement in QOL scores from multivariate analysis. Improvement of OAB item 2 (nocturia) exhibited the greatest influence on improvement in the QOL score. After DBS treatment, 40% of the patients showed significant improvement in urination symptoms (≥2 points reduction in QOL score), 30% of the patients showed mild improvement (1 point reduction in QOL score), and 30% patients showed no improvement (no change in QOL score). No patients exhibited worsening urination symptoms.

CONCLUSION

Most parkinsonian female patients with lower urinary tract symptoms were diagnosed with OAB. DBS treatment improved OAB symptoms. Improvement of nocturia and urgency positively impacts the QOL of female parkinsonian patients.

Deep brain stimulation effects on lower urinary tract function: Systematic review and meta-analysis

INTRODUCTION

While efficacy of deep brain stimulation for motor symptoms of neurological disorders is well accepted, its effects on the autonomic system remain controversial. We aimed to systematically assess all available evidence of deep brain stimulation effects on lower urinary tract function.

METHODS

This systematic review was performed according to the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) statement. Studies were identified by electronic search of Cochrane Central Register of Controlled Trials, Embase, Medline, Scopus, and Web of Science (last search July 12, 2019) and by screening of reference lists and reviews.

RESULTS

After screening 577 articles, we included 29 studies enrolling a total of 1293 patients. Deep brain stimulation of the globus pallidus internus (GPi), pedunculopontine nucleus (PPN), and subthalamic nucleus (STN) had an inhibitory effect on detrusor function, while deep brain stimulation of the ventral intermediate nucleus of the thalamus (VIM) showed an excitatory effect. In the meta-analysis, deep brain stimulation of the STN led to a significant increase in maximum bladder capacity (mean difference 124 mL, 95% confidence interval 60-187 mL, p = 0.0001) but had no clinically relevant effects on other urodynamic parameters. Adverse events (reported in thirteen studies) were most commonly respiratory issues, postural instability, and dysphagia. Risk of bias and confounding was relatively low.

CONCLUSIONS

Deep brain stimulation does not impair lower urinary tract function and might even have beneficial effects. This needs to be considered in the deep brain stimulation decision-making process helping to encourage and to reassure prospective patients.

The Use of Neuromodulation for Symptom Management

Pain and other symptoms of autonomic dysregulation such as hypertension, dyspnoea and bladder instability can lead to intractable suffering. Incorporation of neuromodulation into symptom management, including palliative care treatment protocols, is becoming a viable option scientifically, ethically, and economically in order to relieve suffering. It provides further opportunity for symptom control that cannot otherwise be provided by pharmacology and other conventional methods.

[Is there any obstruction other than prostatic obstruction in Idiopathic Parkinson's Disease?]

OBJECTIVE

To highlight the existence of pseudo-dyssynergia in Idiopathic Parkinson's Disease (IPD) constituting a functional bladder outlet obstruction.

MATERIALS AND METHODS

A retrospective study was conducted by including men with a confirmed diagnose of IPD who participated in the SIROCCO rehabilitation program. Patients included clinically exhibited overactive bladder and voiding dysfunction without prostatic hypertrophy ultrasounded. They have been clinically assessed by the Urinary Symptoms Profile (USP) urinary symptom score. Bladder outlet obstruction was assessed by the pressure-flow study. Urodynamic obstruction has been quantified by the bladder obstruction index which depends on detrusor pressure at maximum flow rate and maximum flow rate. It has been defined by a BOOI>40.

RESULTS

The pressure-flow profile was analyzed in 5 patients who met the inclusion criteria. In this group of 5 patients with IPD, the diagnosis was made on average 10.6 years (7-14) before the pressure-flow studies were performed. Our results objectified 4 patients obstructive among 5 and one equivocal patient. A striated pseudo-dyssynergia was found in the 3 obstructive patients and associated with a smooth pseudodyssynergia in one patient.

CONCLUSION

We have observed, in this short series, a pseudo-dyssynergia by subjects suffering from IPD.

LEVEL OF EVIDENCE

3.

[Neuromodulation of lower urinary tract dysfunction]

Neuromodulative procedures such as transcutaneous electrical nerve stimulation (TENS), transcutaneous/percutaneous tibial nerve stimulation (TTNS/PTNS), and sacral neuromodulation (SNM) are promising second-line treatments for refractory lower urinary tract dysfunction. Using these therapies, both storage and voiding disorders but also bowel dysfunction might be successfully treated. Although the mechanism of action of neuromodulation is not well understood, it seems to involve modulation of spinal cord reflexes and brain networks by peripheral afferents (genital/rectal, tibial and sacral afferents in the case of TENS, TTNS/PTNS, and SNM, respectively). Neuromodulative procedures might also be highly effective in the most desperate situations and further relevant developments are expected so that these innovative techniques will most likely become even more important in urology.

Urinary symptoms are correlated with quality of life after deep brain stimulation in Parkinson's disease

AIMS

Deep brain stimulation (DBS) is known to dramatically improve motor complications in patients with Parkinson's disease (PD), but its effect on urinary symptoms and health-related quality of life (HRQOL) remains unknown. We aimed to examine the relationship between urinary symptoms and HRQOL in patients with PD who underwent DBS.

METHODS

The International Prostate Symptom Score (IPSS) and overactive bladder symptom score (OABSS) were determined to evaluate urinary symptoms in patients with PD who underwent DBS. Postoperative evaluations were performed at 3 months, 1 year, and 3 years postoperatively. We also performed a urodynamic study (UDS) in 13 patients with PD preoperatively and postoperatively. A follow-up UDS was performed 2.0 ± 0.5 years postoperatively.

RESULTS

The preoperative urinary symptoms questionnaire was completed by 28 patients, of whom 14 completed the postoperative urinary symptoms questionnaire after 3 months, 18 after 1 year, and 10 after 3 years. The mean OABSS and IPSS did not change significantly at any follow-up periods postoperatively. When assessing the relationship between urinary symptoms and HRQOL and motor functions, the OABSS and IPSS showed significant positive correlations with HRQOL at 3 months postoperatively. The OABSS and IPSS showed significant positive correlations with activities of daily living (ADL) during the off-phase at 3 years postoperatively. All urodynamic parameters remained unchanged postoperatively.

CONCLUSIONS

Deep brain stimulation did not significantly affect urinary dysfunctions in patients with PD. Urinary symptoms might partially contribute to HRQOL at 3 months postoperatively and ADL during the off-phase at 3 years postoperatively.

Urological dysfunction in synucleinopathies: epidemiology, pathophysiology and management

OBJECTIVE

Parkinson's disease (PD) and multiple system atrophy (MSA) are major neurogenerative diseases characterized pathologically by abnormal alpha-synuclein aggregation. PD and MSA are clinically characterized by motor disorder and bladder dysfunction (mainly urinary urgency and frequency, also called overactive bladder). However, few literatures are available concerning bladder dysfunction in PD or MSA.

METHOD

A systematic review.

RESULTS

The bladder dysfunction in MSA is more severe than that in PD for large post-void residual or urinary retention. These bladder dysfunctions presumably reflect the different nervous system pathologies. Overactive bladder in PD reflects lesions in the brain, e.g., in the prefrontal-nigrostriatal D1 dopaminergic bladder-inhibitory pathway. Overactive bladder in MSA reflects lesions similar to PD and the cerebellum (bladder-inhibitory), and the urinary retention in MSA presumably reflects lesions in the pontine micturition center and the sacral intermediolateral nucleus of the spinal cord (bladder-facilitatory). Bladder dysfunction not only impairs an individual's quality of life, it can also cause emergency hospitalizations due to acute retention and early institutionalization. Anticholinergics are the first-line treatment for bladder dysfunction in PD and MSA patients, but care should be taken for the management of bladder dysfunction-particularly in MSA patients due to the high prevalence of difficult emptying, which needs clean, intermittent catheterization.

CONCLUSIONS

This review summarizes the epidemiology, pathophysiology, and management of bladder dysfunction in individuals with PD or MSA.

Does deep brain stimulation improve lower urinary tract symptoms in Parkinson's disease?

AIMS

To investigate whether deep brain stimulation (DBS) of the globus pallidus pars interna (GPi) or the subthalamic nucleus (STN) improve lower urinary tract symptoms (LUTS) in advanced Parkinson's disease (PD).

METHODS

An exploratory post-hoc analysis was performed of specific LUTS items of questionnaires used in a randomized clinical trial with 128 patients (NSTAPS study). First, we compared scores on LUTS items at baseline and 12 months for the GPi DBS and STN DBS group separately. Second, we divided the group by sex, instead of DBS location; to assess a possible gender associated influence of anatomical and pathophysiological differences, again comparing scores at baseline and 12 months. Third, we reported on Foley-catheter use at baseline and after 12 months.

RESULTS

Urinary incontinence and frequency improved after both GPi DBS and STN DBS at 12 months, postoperatively, but this was only statistically significant for the STN DBS group (P = 0.004). The improvements after DBS were present in both men (P = 0.01) and women (P = 0.05). Nocturia and urinary incontinence did not improve significantly after any type of DBS, irrespective of sex. At 12 months, none of the patients had a Foley-catheter.

CONCLUSIONS

Urinary incontinence and frequency significantly improved after STN DBS treatment in male and female patients with PD. Nocturia and nighttime incontinence due to parkinsonism did not improve after DBS, irrespective of gender.

Central control of micturition in women: Brain-bladder pathways in continence and urgency urinary incontinence

Urinary incontinence disproportionately affects women. Anatomical textbooks typically describe continence mechanisms in women in the context of the pelvic floor support of the urinary bladder and the urethral sphincters. However, the urinary bladder and urethral sphincters are under the central control of the brain through a complex network of neurons that allow storage of urine followed by voiding when socially appropriate. Recent studies suggest that the most common type of urinary incontinence in women, urgency urinary incontinence, involves significant dysfunction of the central control of micturition. In this paper, we review the anatomy and functional connectivity of the nervous system structures involved in the control of micturition. Clinical application of this anatomy in the context of urgency urinary incontinence is also discussed. Understanding the anatomy of the neural structures that control continence will allow clinicians to better understand the underlying pathology of urge incontinence and consider new ways of treating this distressing condition. Clin. Anat. 30:373-384, 2017. © 2017 Wiley Periodicals, Inc.

Prevalence and treatment of LUTS in patients with Parkinson disease or multiple system atrophy

The lower urinary tract is controlled by complex neural mechanisms not only in the periphery, but also in the central nervous systems (CNS). Thus, patients with a wide variety of neurological diseases often also have lower urinary tract symptoms (LUTS), including those with Parkinson disease (PD) or multiple system atrophy (MSA). LUTS are common comorbidities associated with both of these neurodegenerative diseases and are likely to impair patients' quality of life. The motor symptoms of PD and MSA often seem similar; however, the pathophysiology, and thus the treatment of LUTS differs considerably. Antimuscarinics are the first-line treatment of storage LUTS in patients with PD or MSA; however, care should be taken in the management of these patients, especially in those with MSA owing to the high risk of inefficient voiding, and thus an increased post-void residual volume. Other treatments of PD-related LUTS include α-adrenoceptor antagonists, which improve voiding dysfunction, transurethral resection of the prostate for bladder outlet obstruction owing to prostate enlargement, and neuromodulation and intradetrusor botulinum toxin injections for storage LUTS. However, more conservative treatments, including intermittent catheterization, are required for LUTS in patients with MSA, owing to the high incidence of impaired detrusor contractility and detrusor-sphincter dyssynergia.

Current Topics in Deep Brain Stimulation for Parkinson Disease

There is a long history of surgical treatment for Parkinson disease (PD). After pioneering trials and errors, the current primary surgical treatment for PD is deep brain stimulation (DBS). DBS is a promising treatment option for patients with medically refractory PD. However, there are still many problems and controversies associated with DBS. In this review, we discuss current issues in DBS for PD, including patient selection, clinical outcomes, complications, target selection, long-term outcomes, management of axial symptoms, timing of surgery, surgical procedures, cost-effectiveness, and new technology.

Treatment Options for Urogenital Dysfunction in Parkinson's Disease

Urogenital dysfunction is commonly reported in Parkinson’s disease (PD), and history taking and a bladder diary form the cornerstone of evaluation. The assessment of lower urinary tract (LUT) symptoms include urinalysis, ultrasonography, and urodynamic studies and help to evaluate concomitant urological pathologies such as benign prostate enlargement. Antimuscarinic medications are the first line treatment for overactive bladder (OAB) symptoms and solifenacin has been specifically studied in PD. Antimuscarininc drugs may exacerbate PD-related constipation and xerostomia, and caution is advised when using these medications in individuals where cognitive impairment is suspected. Desmopressin is effective for the management of nocturnal polyuria which has been reported to be common in PD. Intradetrusor injections of botulinum toxin have been shown to be effective for detrusor overactivity, however, are associated with the risk of urinary retention. Neuromodulation is a promising, minimally invasive treatment for PD-related OAB symptoms. Erectile dysfunction is commonly reported and first line treatments include phosphodiesterase-5 inhibitors. A patient-tailored approach is required for the optimal management of urogenital dysfunction in PD.

Nocturia in Parkinson's Disease: Why Does It Occur and How to Manage?

BACKGROUND

Nocturia is one of the commonest nonmotor symptoms in Parkinson's disease (PD) and has a significant impact on quality of life both for patients and their carers. There exists a relation between nocturia and poor sleep quality, falls, and institutionalization. Nocturia may manifest as a result of reduced functional bladder capacity or nocturnal polyuria; however, most often the cause is multifactorial. Disorders of circadian rhythm regulation are known to occur with sleep disturbances in PD may also contribute to nocturia.

METHODS AND RESULTS

In this review, an overview of the assessment and management of nocturia in patients with PD is presented. History taking, medication review, and a bladder diary form the cornerstone of the evaluation. Urinalysis, ultrasonography, and urodynamic studies help to assess the cause for lower urinary tract symptoms and exclude concomitant pathologies, such as bladder outlet obstruction. Antimuscarinic medications are the first-line treatment for the overactive bladder; however, caution is needed when using these medications in individuals predisposed to cognitive impairment. Desmopressin is effective for managing nocturnal polyuria.

CONCLUSIONS

An individualized approach is recommended to optimize the management of nocturia in PD.

Effects of Deep Brain Stimulation on Autonomic Function

Over the course of the development of deep brain stimulation (DBS) into a well-established therapy for Parkinson's disease, essential tremor, and dystonia, its utility as a potential treatment for autonomic dysfunction has emerged. Dysfunction of autonomic processes is common in neurological diseases. Depending on the specific target in the brain, DBS has been shown to raise or lower blood pressure, normalize the baroreflex, to alter the caliber of bronchioles, and eliminate hyperhidrosis, all through modulation of the sympathetic nervous system. It has also been shown to improve cortical control of the bladder, directly induce or inhibit the micturition reflex, and to improve deglutition and gastric emptying. In this review, we will attempt to summarize the relevant available studies describing these effects of DBS on autonomic function, which vary greatly in character and magnitude with respect to stimulation target.

The hidden sister of motor fluctuations in Parkinson's disease: A review on nonmotor fluctuations

Only a few years after the introduction of levodopa, the first descriptions of motor fluctuations and dyskinesia related to dopaminergic therapy appeared. In PD, attention turned to their management, that had dampened the euphoria of the "levodopa miracle." It soon became clear that neuropsychiatric, autonomic, and sensory features also tend to develop fluctuations after chronic exposure to l-dopa. The diversity of fluctuating nonmotor symptoms, their largely subjective nature, coupled with a frequent lack of insight led to difficulties in identification and quantification. This may explain why, despite the high impact of nonmotor symptoms on patient autonomy and quality of life, evaluation of nonmotor fluctuations is not part of clinical routine. In view of the lack of specific validated assessment tools, detailed anamnesis should ideally be coupled with an evaluation in both ON and OFF drug conditions. The mechanisms of nonmotor fluctuations are not well understood. It is thought that they share dopaminergic presynaptic pharmacokinetic and postsynaptic pharmacodynamic mechanisms with the classical motor complications, but involve different neural pathways. Although symptoms fluctuate with dopaminergic treatment, serotonine and norepinephrine denervation, as well as interactions between neurotransmitter systems, probably contribute to their diversity. The lack of validated tools for assessment of these phenomena explains the almost complete absence of treatment studies. Management, largely resulting from expert opinion, includes psychiatric follow-up, nondopaminergic drugs, and advanced dopaminergic treatment, including drug delivery pumps and DBS. This review aims to provide a starting point for the understanding, diagnosis, and management of nonmotor fluctuations. © 2016 International Parkinson and Movement Disorder Society.

The Impact of Pallidal and Subthalamic Deep Brain Stimulation on Urologic Function in Parkinson's Disease

OBJECTIVE

Deep Brain Stimulation (DBS) is an established adjunctive surgical intervention for treating Parkinson's disease (PD) motor symptoms. Both surgical targets, the globus pallidus interna (GPi) and subthalamic nucleus (STN), appear equally beneficial when treating motor symptoms but effects on nonmotor symptoms are not clear. Lower urinary tract symptoms (LUTS) are a common PD complaint. Given prior data in STN-DBS, we aimed to further explore potential benefits in LUTS in both targets.

METHODS

We performed a prospective, nonblinded clinical trial evaluating LUTS in PD patients in both targets pre and post DBS using validated urologic surveys. Participants were already slated for DBS and target selection predetermined before study entry. LUTS was evaluated using: the American Urological Association (AUA-SI), Quality of Life score (QOL), Overactive Bladder 8 Questionnaire (OAB-q), and Sexual Health Inventory for Men (SHIM).

RESULTS

Of 33 participants, 20 underwent STN DBS and 13 had GPi DBS. Patients demonstrated moderate baseline LUTS. The urologic QOL score significantly improved post DBS (3.24 ± 1.77vs. 2.52 ± 1.30; p = 0.03). Analyzed by target, only the STN showed significant change in QOL (3.20 ± 1.61 vs 2.25 ± 1.33; p = 0.04). There were no other significant differences in urologic scores post DBS noted in either target.

CONCLUSION

In PD patients with moderate LUTS, there were notable improvements in QOL for LUTS post DBS in the total sample and STN target. There may be differences in DBS effects on LUTS between targets but this will require further larger, blinded studies.

Nonmotor Symptoms and Subthalamic Deep Brain Stimulation in Parkinson's Disease

Subthalamic deep brain stimulation (STN DBS) is an established treatment for the motor symptoms in patients with advanced Parkinson’s disease (PD). In addition to improvements in motor symptoms, many studies have reported changes in various nonmotor symptoms (NMSs) after STN DBS in patients with PD. Psychiatric symptoms, including depression, apathy, anxiety, and impulsivity, can worsen or improve depending on the electrical stimulation parameters, the locations of the stimulating contacts within the STN, and changes in medications after surgery. Global cognitive function is not affected by STN DBS, and there is no increase in the incidence of dementia after STN DBS compared to that after medical treatment, although clinically insignificant declines in verbal fluency have been consistently reported. Pain, especially PD-related pain, improves with STN DBS. Evidence regarding the effects of STN DBS on autonomic symptoms and sleep-related problems is limited and remains conflicting. Many symptoms of nonmotor fluctuations, which are occasionally more troublesome than motor fluctuations, improve with STN DBS. Although it is clear that NMSs are not target symptoms for STN DBS, NMSs have a strong influence on the quality of life of patients with PD, and clinicians should thus be aware of these NMSs when deciding whether to perform surgery and should pay attention to changes in these symptoms after STN DBS to ensure the optimal care for patients.

A guideline for the management of bladder dysfunction in Parkinson's disease and other gait disorders

Parkinson's disease (PD) is a common neurodegenerative disorder, and lower urinary tract (LUT) dysfunction is one of the most common autonomic disorders with an estimated incidence rate of 27-80%. Studies have shown that bladder dysfunction significantly influences quality-of-life (QOL) measures, early institutionalisation, and health economics. We review the pathophysiology of bladder dysfunction in PD, lower urinary tract symptoms (LUTS), objective assessment, and treatment options. In patients with PD, disruption of the dopamine D1-GABAergic direct pathway may lead to LUTS. Overactive bladder (OAB) is the most common LUT symptom in PD patients, and an objective assessment using urodynamics commonly shows detrusor overactivity (DO) in these patients. The post-void residual (PVR) volume is minimal in PD, which differs significantly from multiple system atrophy (MSA) patients who have a more progressive disease that leads to urinary retention. However, subclinical detrusor weakness during voiding may also occur in PD. Regarding bladder management, there are no large, double-blind, prospective studies in this area. It is well recognised that dopaminergic drugs can improve or worsen LUTS in PD patients. Therefore, an add-on therapy with anticholinergics is required. Beta-3 adrenergic agonists are a potential treatment option because there are little to no central cognitive events. Newer interventions, such as deep brain stimulation (DBS), are expected to improve bladder dysfunction in PD. Botulinum toxin injections can be used to treat intractable urinary incontinence in PD. Transurethral resection of the prostate gland (TURP) for comorbid BPH in PD is now recognised to be not contraindicated if MSA is excluded. Collaboration of urologists with neurologists is highly recommended to maximise a patients' bladder-associated QOL. Neurourol. Urodynam. 35:551-563, 2016. © 2015 Wiley Periodicals, Inc.

Deep brain stimulation and multiple sclerosis: Therapeutic applications

Deep brain stimulation is a neurosurgical technique that can be used to alleviate symptoms in a growing number of neurological conditions through modulating activity within brain networks. Certain applications of deep brain stimulation are relevant for the management of symptoms in multiple sclerosis. In this paper we discuss existing treatment options for tremor, facial pain and urinary dysfunction in multiple sclerosis and discuss evidence to support the potential use of deep brain stimulation for these symptoms.

Control of the lungs via the human brain using neurosurgery

Neurosurgery can alter cardiorespiratory performance via central networks and includes deep brain stimulation (DBS), a routinely employed therapy for movement disorders and chronic pain syndromes. We review the established cardiovascular effects of DBS and the presumed mechanism by which they are produced via the central autonomic network. We then review the respiratory effects of DBS, including modulation of respiratory rate and lung function indices, and the mechanisms via which these may occur. We conclude by highlighting the potential future therapeutic applications of DBS for intractable airway diseases.

Summary of the recommendations of the EFNS/MDS-ES review on therapeutic management of Parkinson's disease

OBJECTIVE

To summarize the 2010 EFNS/MDS-ES evidence-based treatment recommendations for the management of Parkinson's disease (PD). This summary includes the treatment recommendations for early and late PD.

METHODS

For the 2010 publication, a literature search was undertaken for articles published up to September 2009. For this summary, an additional literature search was undertaken up to December 2010. Classification of scientific evidence and the rating of recommendations were made according to the EFNS guidance. In cases where there was insufficient scientific evidence, a consensus statement ('good practice point') is made.

RESULTS AND CONCLUSIONS

For each clinical indication, a list of therapeutic interventions is provided, including classification of evidence.

[Lower urinary tract dysfunctions in parkinsonian syndromes: a review by the Neuro-Urology Comittee of the French Association of Urology]

INTRODUCTION

Lower urinary tract disorders (LUTD) are common in Parkinson's disease (PD) and other parkinsonian syndromes (PS). They are responsible for a significant morbidity and mortality and impair patients' quality of life. The therapeutic management of these LUTD requires to know how to distinguish the PD from other PS and their epidemiology and pathophysiology.

OBJECTIVE

To provide a diagnostic and therapeutic management of LUTD in patients with PS.

METHOD

A review of litterature using PubMed library was performed using the following keywords: Parkinson's disease, multiple system atrophy, lower urinary tract disorders, neurogenic bladder, overactive bladder, obstruction, anticholinergics, dopamine, prostate surgery.

RESULTS

Sometimes revealing the neurological disease, LUTD in PS raise a diagnostic problem because they occur at an age when various urogynecological disorders can be intricated with neurogenic bladder dysfunction. The differential diagnosis between PD and multiple system atrophy is important to know by the urologist. The distinction is based on the semiological analysis, the clinical response to dopaminergic therapy and the clinical outcome but also on data from urodynamic explorations. The therapeutic management of these LUTD cannot be easy due to the difficulty of use of some pharmacological treatments and the risk of deterioration after inappropriate surgery. The different treatments include the careful use of anticholinergics, posterior tibial nerve stimulation, deep thalamic stimulation and low-dose intradetrusor injections of botulinum toxin without approval. The decision to perform prostate surgery will be taken with caution after proving the bladder obstruction.

CONCLUSION

When analysing LUTD in PS, the urologist must know to question the initial diagnosis of PD. Treatments in order to reduce morbidity and mortality of these LUTD and to improve the quality of life of patients suffering from these degenerative diseases, will be proposed after multidisciplinary neuro-urologic concertation. The decision to perform prostate surgery must be taken with caution after proving sub-vesical obstruction.

The micturition switch and its forebrain influences

Dr DeGroat and Wickens has reviewed the central neural mechanisms controlling the lower urinary tract with a major focus on the brain stem circuitry that mediates the switch-like characteristics of micturition, in particular the periaqueductal grey and the pontine micturition centre (de 2012). The review culminates in a computer model of how the brainstem switch operates in animals in which forebrain influences on micturition have been removed by decerebration. In this complementary paper, we review the mechanisms of forebrain involvement in the voluntary control of human micturition and the maintenance of continence with evidence based heavily on the results of functional brain imaging experiments.

Nonmotor outcomes in Parkinson's disease: is deep brain stimulation better than dopamine replacement therapy?

Nonmotor symptoms are an integral part of Parkinson's disease and cause significant morbidity. Pharmacological therapy helps alleviate the disease but produces nonmotor manifestations. While deep brain stimulation (DBS) has emerged as the treatment of choice for motor dysfunction, the effect on nonmotor symptoms is not well known. Compared with pharmacological therapy, bilateral subthalamic nucleus (STN)-DBS or globus pallidum interna (GPi)-DBS has significant beneficial effects on pain, sleep, gastrointestinal and urological symptoms. STN-DBS is associated with a mild worsening in verbal fluency while GPi-DBS has no effect on cognition. STN-DBS may improve cardiovascular autonomic disturbances by reducing the dose of dopaminergic drugs. Because the motor effects of STN-DBS and GPi-DBS appear to be similar, nonmotor symptoms may determine the target choice in surgery of future patients.

The autonomic effects of deep brain stimulation--a therapeutic opportunity

Deep brain stimulation (DBS) is an expanding field in neurosurgery and has already provided important insights into the fundamental mechanisms underlying brain function. One of the most exciting emerging applications of DBS is modulation of blood pressure, respiration and micturition through its effects on the autonomic nervous system. DBS stimulation at various sites in the central autonomic network produces rapid changes in the functioning of specific organs and physiological systems that are distinct from its therapeutic effects on central nervous motor and sensory systems. For example, DBS modulates several parameters of cardiovascular function, including heart rate, blood pressure, heart rate variability, baroreceptor sensitivity and blood pressure variability. The beneficial effects of DBS also extend to improvements in lung function. This article includes an overview of the anatomy of the central autonomic network, which consists of autonomic nervous system components in the cortex, diencephalon and brainstem that project to the spinal cord or cranial nerves. The effects of DBS on physiological functioning (particularly of the cardiovascular and respiratory systems) are discussed, and the potential for these findings to be translated into therapies for patients with autonomic diseases is examined.

Pathophysiology of bladder dysfunction in Parkinson's disease

Bladder dysfunction (urinary urgency/frequency) is a common non-motor disorder in Parkinson's disease (PD). In contrast to motor disorders, bladder dysfunction is sometimes non-responsive to levodopa treatment. The brain pathology causing the bladder dysfunction (appearance of overactivity) involves an altered dopamine basal ganglia-frontal circuit, which normally suppresses the micturition reflex. The pathophysiology of the bladder dysfunction in PD differs from that in multiple system atrophy; therefore, it might aid in differential diagnosis. Anticholinergic agents are used to treat bladder dysfunction in PD, although these drugs should be used with caution particularly in elderly patients who have cognitive decline. These treatments might be beneficial in maximizing the patients' quality of life.

Bladder, bowel, and sexual dysfunction in Parkinson's disease

Bladder dysfunction (urinary urgency/frequency), bowel dysfunction (constipation), and sexual dysfunction (erectile dysfunction) (also called “pelvic organ” dysfunctions) are common nonmotor disorders in Parkinson's disease (PD). In contrast to motor disorders, pelvic organ autonomic dysfunctions are often nonresponsive to levodopa treatment. The brain pathology causing the bladder dysfunction (appearance of overactivity) involves an altered dopamine-basal ganglia circuit, which normally suppresses the micturition reflex. By contrast, peripheral myenteric pathology causing slowed colonic transit (loss of rectal contractions) and central pathology causing weak strain and paradoxical anal sphincter contraction on defecation (PSD, also called as anismus) are responsible for the bowel dysfunction. In addition, hypothalamic dysfunction is mostly responsible for the sexual dysfunction (decrease in libido and erection) in PD, via altered dopamine-oxytocin pathways, which normally promote libido and erection. The pathophysiology of the pelvic organ dysfunction in PD differs from that in multiple system atrophy; therefore, it might aid in differential diagnosis. Anticholinergic agents are used to treat bladder dysfunction in PD, although these drugs should be used with caution particularly in elderly patients who have cognitive decline. Dietary fibers, laxatives, and “prokinetic” drugs such as serotonergic agonists are used to treat bowel dysfunction in PD. Phosphodiesterase inhibitors are used to treat sexual dysfunction in PD. These treatments might be beneficial in maximizing the patients' quality of life.

Effect of unilateral subthalamic deep brain stimulation on rat digestive motor activity

A significant proportion of patients with Parkinson's disease suffers from digestive symptoms. Bilateral deep brain stimulation of the subthalamic nucleus has become a reliable therapeutic option for parkinsonian patients, but its effects on digestive motility remain poorly investigated. The aim of our study was to assess whether subthalamic stimulation could induce changes in gastric, colonic, and rectal motility and modulate brain centers involved in gut motility.

METHODS

In anesthetized rats, unilateral subthalamic nucleus stereotactic implantation was performed while intra-gastric, -colonic, and -rectal pressures were recorded during the ON and OFF periods of the stimulation. c-Fos protein expression was quantified by immunostaining in the nucleus of the solitary tract, the dorsal motor nucleus of the vagus nerve, the locus coeruleus, and the Barrington's nucleus.

RESULTS

Compared to baseline, sham stimulation did not change phasic gastric, colonic or rectal motor activity. Unilateral subthalamic stimulation increased colonic phasic motility (P<0.05) compared to baseline and the OFF period with no change in gastric and rectal motility. Pre-treatment with atropine, or specific D1 and D2 receptors antagonists prevented the rise in colonic motor activity. An increase in c-Fos protein-positive cells within all the studied nuclei was observed in the stimulated group compared to the sham group.

CONCLUSIONS

Unilateral subthalamic stimulation impacts on gut motility in anesthetized rats with a significant increase in colonic motility probably via the modulation of several brain centers. These findings warrant further confirmation in parkinsonian rat models before being transposed to clinical conditions.

Deep brain stimulation state of the art and novel stimulation targets

Levodopa therapy represents a major breakthrough in the treatment of Parkinson's disease (PD). As time and disease severity progresses, however, the shortcomings and adverse effects of this neurotransmitter replacement strategy become apparent and patients develop disabilities despite best medical therapy. The heightened awareness of these difficulties has given birth to a re-examination of functional neurosurgery for advanced PD. In the 20 years since the renewed interest in deep brain stimulation (DBS), approximately 60,000 patients with PD have undergone this surgery, with an annual accrual of 8000-10,000 new patients per year worldwide. Clinical studies have confirmed the beneficial effects of DBS surgery for the treatment of the cardinal motor features of PD. The likelihood of improvement, however, varies from symptom to symptom and from patient to patient. Surgery is very effective in reducing the motor fluctuations and dyskinesias--the primary reasons for patients' intolerance to medical therapy. Other problems are less or non-responsive. Further, despite the widespread use of this technology, the mechanism through which DBS alleviates symptoms is not fully understood. This review will discuss the patient population most likely to benefit from surgery, what aspects of the disease are most responsive, the current limitations of DBS, and new therapeutic targets that are being examined to address these limitations.

PET functional imaging of deep brain stimulation in movement disorders and psychiatry

Deep brain stimulation (DBS) represents a major advance in the treatment of various severe movement disorders or neuropsychiatric diseases. Our understanding of the mechanism of action of this surgical treatment has greatly benefited from functional imaging studies. Most of these studies have been conducted in patients with Parkinson's disease (PD) treated by bilateral subthalamic nucleus (STN) stimulation. These studies have notably underlined the fact that STN stimulation influences motor, limbic, or associative cortical-subcortical loops in various (sometimes contradictory) ways. We present an up-to-date review of the information provided by functional imaging studies in surgery for PD, dystonia, tremor, as well as in psychiatric disorders such as depression or obsessive-compulsive disorder. On the basis of this information, proposed mechanisms of action of DBS are discussed, as well as the need for additional approaches such as improved anatomical localization of the contact used for stimulation or a better understanding of the electrical distribution around the electrode.

Lesions outside the CNS in Parkinson's disease

Parkinson's disease (PD) is not a simple movement disorder induced just by loss of dopaminergic neurons in the substantia nigra pars compacta. Apparently, the substantia nigra is not the only or the first brain region damaged in PD. Moreover, older and recent studies have shown that the degenerative process in PD is much more extensive and affects not only the central nervous system (CNS) but also the peripheral autonomic nervous system and the organs outside the brain that the latter innervates. These include mainly the gastrointestinal tract, the heart, kidneys, urogenital system, and skin. Additional extra-CNS organs that are involved in PD include the eye and the adrenal gland. This article reviews the anatomical, physiological, and clinical features of extracerebral manifestations of PD, and describes their relevance to the etiology and pathogenesis of the disease. It establishes this illness as a systemic CNS and peripheral disorder that warrants new hypotheses regarding its causation and progression.

Isolation of the brain-related factor of the error between intended and achieved position of deep brain stimulation electrodes implanted into the subthalamic nucleus for the treatment of Parkinson's disease

OBJECTIVE

Although a few studies have quantified errors in the implantation of deep brain stimulation electrodes into the subthalamic nucleus (STN), a significant trend in error direction has not been reported. We have previously found that an error in axial plane, which is of most concern because it cannot be compensated for during deep brain stimulation programming, had a posteromedial trend. We hypothesized that this trend results from a predominance of a directionally oriented error factor of brain origin. Accordingly, elimination of nonbrain (technical) error factors could augment this trend. Thus, implantation accuracy could be improved by anterolateral compensation during target planning.

METHODS

Surgical technique was revised to minimize technical error factors. During 22 implantations, targets were selected on axial magnetic resonance imaging scans up to 1.5 mm anterolateral from the STN center. Using fusion of postoperative computed tomographic and preoperative magnetic resonance imaging scans, implantation errors in the axial plane were obtained and compared with distances from the lead to the STN to evaluate the benefit of anterolateral compensation.

RESULTS

Twenty errors and the mean error had a posteromedial direction. The average distances from the lead to the target and to the STN were 1.7 mm (range, 0.8-3.1 mm) and 1.1 mm (range, 0.1-1.9 mm), respectively. The difference between the 2 distances was significant (paired t test, P < 0.0001). The lower parts of the lead were consistently bent in the posteromedial direction on postoperative scout computed tomographic scans, suggesting that a brain-related factor is responsible for the reported error.

CONCLUSION

Elimination of the technical factors of error during STN deep brain stimulation implantation can result in a consistent posteromedial error. Implantation accuracy may be improved by compensation for this error in advance.