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

Deep brain stimulation of the subthalamic nucleus for the treatment of Parkinson's disease

High-frequency deep brain stimulation (DBS) of the subthalamic nucleus (STN-HFS) is the preferred surgical treatment for advanced Parkinson's disease. In the 15 years since its introduction into clinical practice, many studies have reported on its benefits, drawbacks, and insufficiencies. Despite limited evidence-based data, STN-HFS has been shown to be surgically safe, and improvements in dopaminergic drug-sensitive symptoms and reductions in subsequent drug dose and dyskinesias are well documented. However, the procedure is associated with adverse effects, mainly neurocognitive, and with side-effects created by spread of stimulation to surrounding structures, depending on the precise location of electrodes. Quality of life improves substantially, inducing sudden global changes in patients' lives, often requiring societal readaptation. STN-HFS is a powerful method that is currently unchallenged in the management of Parkinson's disease, but its long-term effects must be thoroughly assessed. Further improvements, through basic research and methodological innovations, should make it applicable to earlier stages of the disease and increase its availability to patients in developing countries.

Effect of Thalamic Deep Brain Stimulation on Lower Urinary Tract Function

OBJECTIVE

The precise mechanisms underlying cerebral regulation of lower urinary tract function are still poorly understood. In patients with disabling essential tremor (ET) refractory to pharmacotherapy, thalamic deep brain stimulation (DBS) is an effective treatment for tremor control. Here, we evaluated the effect of thalamic DBS on urodynamic parameters in patients with ET.

PATIENTS AND METHODS

We investigated seven patients (two females, five males) with ET 15-85 mo after implantation of DBS leads into the ventral intermediate nucleus of the thalamus. We compared urodynamic parameters during thalamic DBS (ON state) and 30 min after turning the stimulator off (OFF state).

RESULTS

In the ON compared with the OFF state, there was a significant decrease in bladder volume at first desire to void (median, 218 ml vs. 365 ml, p=0.031), at strong desire to void (median, 305 ml vs. 435 ml, p=0.031), and at maximum cystometric capacity (median, 345 ml vs. 460 ml, p=0.016). No significant differences between the ON and OFF state were detected for changes in detrusor pressure during filling cystometry, bladder compliance, maximum detrusor pressure, detrusor pressure at maximum flow rate, maximum flow rate, voided volume, and postvoid residual.

CONCLUSIONS

Thalamic deep brain stimulation resulted in an earlier desire to void and decreased bladder capacity, suggesting a regulatory role of the thalamus in lower urinary tract function. Therefore, the thalamus may be a promising target for the development of new therapies for lower urinary tract dysfunction.

Management of non-motor symptoms in advanced Parkinson disease

Progress in pharmacology has markedly improved the treatment of early Parkinson's disease. The management of advanced Parkinson's symptoms, however, remains a challenge. These symptoms are divided into motor and non-motor symptoms. Non-motor symptoms may appear early or late in the disease and sometimes even before the onset of the first motor symptoms confirming the diagnosis. The spectrum of non-motor symptoms encompasses autonomic dysfunctions, sleep disorders, mood disorders, impulse control disorders, cognitive dysfunction, dementia, paranoia and hallucinations. They are often less appreciated than motor symptoms but are important sources of disability for many PD patients. This review describes these non-motor symptoms and their managements.

Motor and Nonmotor Symptom Follow-Up in Parkinsonian Patients after Deep Brain Stimulation of the Subthalamic Nucleus

OBJECTIVE

To evaluate motor and nonmotor symptoms in patients with Parkinson's disease undergoing bilateral deep brain stimulation of the subthalamic nucleus (STN DBS).

METHODS

Thirty-six consecutive patients receiving bilateral STN stimulation implants were evaluated preoperatively as well as 12 and 24 months after surgery. Motor symptoms were assessed through the Unified Parkinson's Disease Rating Scale (UPDRS). Data concerning nonmotor symptoms were collected from items of the UPDRS and 2 additional questions from clinical charts regarding constipation and urological dysfunction.

RESULTS

STN DBS was effective in controlling motor symptoms; concerning nonmotor symptoms, sleep quality and constipation improved after surgery as compared to baseline. Salivation, swallowing and sensory complaints were ameliorated to a comparable degree by the medication on state, whether preoperatively or postoperatively. With a lower dose of dopaminergic medication, however, the medication on state appeared to be a much larger percentage of the day postoperatively. No significant variations were detected in intellectual impairment, depression, thought disorders, motivation, falling unrelated to freezing, nausea, orthostatic hypotension and urological dysfunction.

CONCLUSIONS

STN DBS effectively controls motor symptoms, while nonmotor features of advanced Parkinson's disease patients are mostly unchanged after surgery, even though some specific aspects, notably sleep complaints and constipation, are ameliorated.

Chapitre I - Troubles vésico-sphintériens des syndromes parkinsoniens

Lower urinary tract dysfunction is frequent in Parkinson's disease and other Parkinsonian syndromes and can cause urinary incontinence complicating a urgency-frequency syndrome or on the contrary, dysuria. These disorders are a frequent urological presenting complaint due to their impact on the patient's quality of life. Urologists must be aware of the different natural histories of diseases such as Parkinson's disease and Parkinsonian syndromes such as multisystem atrophy, which often have a severe course and are marked by resistance to neuropharmacological treatments. These various diseases can also directly induce urinary symptoms, independently of urological complications. Inversely, the development of urinary disorders, especially obstructive symptoms, in a patient with Parkinsonian syndrome may require review of the neurological diagnosis. Finally, therapeutic management is complex due to the difficulty of using pharmacological treatments, and the risk of deterioration after surgical treatment of obstructive uropathy.

Lower urinary tract symptoms and bladder control in advanced Parkinson's disease: effects of deep brain stimulation in the subthalamic nucleus

Deep brain stimulation in the subthalamic nucleus (STN) leads to significant improvement in motor function in patients with advanced Parkinson's disease (PD). In this prospective study including 16 patients with PD, we investigated (1) lower urinary tract symptoms (LUTS) by questionnaires International Prostate Symptom Score (IPSS, symptoms only) and Danish Prostate Symptom Score (DanPSS, symptoms and bother of symptoms) and (2) bladder control (assessed by urodynamics) before and after implantation of electrodes in the STN. PD symptoms (Unified Parkinson's Disease Rating Scale score) improved significantly (P < 0.0001), and symptoms of overactive bladder (IPSS) decreased along with the troublesome symptoms of overactive bladder (DanPSS; P < 0.01 for both). Urodynamic parameters before and after implantation of electrodes in the STN, evaluated with and without the stimulation on, did not change significantly.

Overactive bladder in Parkinson's disease: alteration of brainstem raphe detected by transcranial sonography

Urinary dysfunction is very common in idiopathic Parkinson's disease (PD) and manifests primarily with symptoms of overactive bladder (OAB). Affection of central serotonergic systems has been suggested to play a role in OAB. The objective of this study was to evaluate whether in PD patients with OAB symptoms a specific alteration of the brainstem raphe (BR), which contains serotonergic neurons, can be detected with transcranial sonography (TCS). Of 116 PD patients enrolled, 19 had PD-related OAB symptoms (OAB+) unlike remaining 97 patients (OAB-). Patients were examined by a sonographer blinded to the clinical data. Reduced echogenicity of BR was found in 12 (63%) OAB+ patients but only in 18 (19%) of 93 assessable OAB- patients (Mann-Whitney U-test, P < 0.001). In OAB+ patients, lower raphe echogenicity score was associated with longer duration of OAB symptoms (anova, P = 0.033). Other TCS findings such as echogenicity of substantia nigra, thalami, lenticular and caudate nuclei, and widths of third and lateral ventricles did not differ between OAB+ and OAB- patients. TCS findings suggest a pathogenetic role of BR in OAB related to PD. Alterations may reflect disturbance of its central serotonergic system.

Correlation Between the Overactive Bladder Questionnaire (OAB-q) and Urodynamic Data of Parkinson Disease Patients Affected by Neurogenic Detrusor Overactivity During Antimuscarinic Treatment

INTRODUCTION

Parkinson disease (PD) patients present urinary symptoms during the course of the disease, very often suggestive of overactive bladder and sustained by neurogenic detrusor overactivity. These symptoms cause a severe lowering of quality of life determining social withdrawal and they need to be early diagnosed to restore social interaction and prevent urinary tract complications. Today overactive bladder diagnosis is easier, thanks to the availability of new investigative tools, particularly voiding questionnaires. The aim of the present study was to evaluate the reliability of the Overactive Bladder screener (OAB screener/OAB-questionnaire), a new voiding questionnaire specifically developed for the overactive bladder diagnosis in PD subjects suffering from overactive bladder symptoms. Clinical data obtained by the questionnaire were compared with urodynamic outcomes, at basal conditions and after antimuscarinic treatment, to better explorate the questionnaire reliability.

MATERIALS AND METHODS

Forty PD patients have been enrolled in the protocol, and submitted to the OAB screener, voiding diary and urodynamic investigation before and after antimuscarinic treatment. OAB-score and urodynamic parameters were statistically analyzed and compared.

RESULTS

The OAB-q well correlated with voiding diary and urodynamic data of Parkinson subjects either at baseline or after the antimuscarinic treatment. The study suggests that this clinical tool might be used for neurogenic overactive bladder diagnosis and that it seems to be a useful outcome measure for treatments of neurogenic OAB.

Voluntary pelvic floor muscle control—an fMRI study

Storage and periodic expulsion of urine by the bladder are controlled by central pathways and organized as simple on-off switching circuits. Several reports concerning aspects of micturition control have identified distinct regions in the brainstem, like the pontine micturition center (PMC) and the periaqueductal gray (PAG), as well as the cerebellum, basal ganglia, limbic system, and cortical areas that are organized in a widespread network. The present study focused on the involvement of these specific brain regions in pelvic floor muscle control. Functional magnetic resonance imaging (fMRI) was performed at 3T in 11 healthy women with urge to void due to a filled bladder, who were instructed to either imitate voiding by releasing or to imitate interruption of voiding by contracting pelvic floor muscles. None of the subjects was able to start voiding during the experiments, presumably due to subconscious restraint resulting from the inconvenient situation. Relaxation and contraction of pelvic floor muscles induced strong and similar activation patterns including frontal cortex, sensory-motor cortex, cerebellum, and basal ganglia. Furthermore, well-localized activations in the PMC and the PAG were identified. To our knowledge, this is the first study using fMRI to demonstrate micturition-related activity in these brainstem structures. The presented approach proved to characterize the widespread central network in pelvic floor muscle control. Thus, in patients with voiding dysfunction, fMRI will be useful to elucidate the individual disturbance level.

Bladder dysfunction in Parkinsonism: Mechanisms, prevalence, symptoms, and management

The advent of functional imaging methods has increased our understanding of the neural control of the bladder. This review examines current concepts of the role of brain function in urinary control with particular emphasis on the putative role of dopamine receptors. Dopaminergic mechanisms play a profound role in normal bladder control and the dysfunction of these may result in symptoms of overactive bladder in Parkinsonism. The importance of this nonmotor disorder has been overlooked. We address the problem of bladder dysfunction as it presents to patients and their neurologist. The prevalence of bladder symptoms in Parkinson's disease is high; the most common complaint is nocturia followed by frequency and urgency. In multiple-system atrophy, the combination of urge and urge incontinence and poor emptying may result in a complex combination of complaints. The management of bladder dysfunction in Parkinsonism addresses treatment of overactive detrusor as well as incontinence.

Update on the neurology of Parkinson's disease

The differential diagnosis of a patient with apparent Parkinson's Disease (PD) and bladder symptoms is considered and the bladder dysfunction of Multiple System Atrophy (MSA) is reviewed. Recent insights into the progression of the neuropathology of PD have enabled thinking about the stage of the disease at which bladder dysfunction is likely to occur and the expected clinical context of the problem. Bladder symptoms of neurological origin are likely in a patient who has had treated motor symptoms for some years and in whom the ongoing neuropathology has progressed beyond involvement of the basal ganglia, so that symptoms due to cortical dysfunction as well as the adverse effects of dopaminergic medication are also confounding factors. Bladder symptoms in a man with lesser neurological disability should be investigated to exclude underlying outflow obstruction. Possible management options are considered.

An fMRI study of the role of suprapontine brain structures in the voluntary voiding control induced by pelvic floor contraction

We have learned that micturition is comprised of two basic phases: storage and emptying; during bladder emptying, the pontine and periaqueductal gray (PAG) micturition center ensures coordinated inhibition of striated sphincter and pelvic floor muscles and relaxation of the internal urethral sphincter while the detrusor muscle contracts. Due to several disorders of the brain and spinal cord, the achieved voluntary control of bladder function can be impaired, and involuntary mechanisms of bladder activation again become evident. However, little has been discovered so far how higher brain centers strictly regulate the intricate process of micturition. The present functional magnetic resonance imaging (fMRI) study attempted to identify brain areas involved in such voluntary control of the micturition reflex by performing functional magnetic resonance imaging during a block design experiment in 12 healthy subjects. The protocol consisted of alternating periods of rest and pelvic muscle contraction during empty-bladder condition (EBC) and full-bladder condition (FBC). Repeated pelvic floor muscle contractions were performed during full bladder to induce a stronger contrast of bladder sensation, desire to void and inhibition of the micturition reflex triggering, since the subjects were asked not to urinate. Empty-bladder conditions were applied as control groups. Activation maps calculated by contrast of subtracting the two different conditions were purposed to disclose these brain areas that are involved during the inhibition of the micturition reflex, in which contrast, the SMA, bilateral putamen, right parietal cortex, right limbic system, and right cerebellum were found activated. The combined activation of basal ganglia, parietal cortex, limbic system, and cerebellum might support the assumption that a complex visceral sensory-motor program is involved during the inhibitory control of the micturition reflex.

The risk of bladder and autonomic dysfunction in a community cohort of Parkinson's disease patients and normal controls

A questionnaire investigating bladder problems, symptoms of autonomic dysfunction, social handicap and depression was mailed to a sample of patients with Parkinson's disease (PD) and to elderly control subjects without PD. The patients reported two-fold greater risk of bladder problems and four-fold risk of autonomic problems compared to the controls. Erectile dysfunction was nearly twice as frequent in patients compared to controls. Depressive symptoms in the PD group were predictive of bladder problems and autonomic impairment and also poorer social functioning and dependency in activities of daily living. No associations between bladder and autonomic dysfunction, age, or severity/duration of PD were found. This investigation shows that the risk of bladder, autonomic and erectile dysfunction is significantly greater in patients with PD compared to a control group.