Bladder control, urgency, and urge incontinence: evidence from functional brain imaging

Using Functional Magnetic Resonance Imaging to Detect Differences in Micturition-Related Brain Activity Between Volitional and Involuntary Detrusor Contractions

INTRODUCTION

Detrusor contractions can be classified as either volitional or involuntary. The latter are a hallmark of urge urinary incontinence. Understanding differences in neuroactivation associated with both types of contractions can help elucidate pathophysiology and therapeutic targets. In this study we aim to compare brain activity associated with voluntary and involuntary detrusor contractions.

METHODS

Twenty seven stroke survivors with secondary storage lower urinary tract symptoms underwent four filling cycles of simultaneous urodynamics and BOLD-signal fMRI. After each fill, participants were instructed to void. Voids inside the designated 10-s period were considered voluntary contractions. All others were considered involuntary. Each contraction was then segmented into phases: Early (10 s before start of contraction), Rise (start of contraction to peak vesical pressure), Plateau, and Fall (from peak pressure to resolution of the contraction). BOLD-effect was compared between the two contraction types, employing a minimum cluster size of 25 voxels and significance threshold at p < 0.005.

RESULTS

Compared to volitional contractions, involuntary contractions were associated with diminished brain activity in each contraction phase. During the Early phase, this difference was most prominent in areas implicated with sensory and autonomic function, shifting to regions tasked with motor control as the contraction continued and eventually attenuating as the contraction resolved.

CONCLUSION

This study uniquely contrasts brain activation associated with volitional and involuntary contractions. Relative to involuntary contractions, volitional contractions revealed increased activity in motor, sensory, and executive functioning regions. These findings reflect both the physiological mechanism of volitional contractions and suggest the displacement of this mechanism by a subcortical reflex in involuntary contractions.

CLINICAL TRIAL REGISTRATION

NCT05301335.

Role of detrusor overactivity and interval between bladder sensations on the severity of overactive bladder symptoms in patients with multiple sclerosis

PURPOSE

This study aimed to assess the relationship between kinetics of bladder sensations perception, detrusor overactivity (DO), and severity of overactive bladder (OAB) symptoms in patients with multiple sclerosis (PwMS).

METHODS

All PwMS who underwent urodynamic assessment including three cystometries (20mL/min, 100mL/min, and 100mL/min with 4°C fluid) between June 2020 and October 2022 were included in this retrospective study. Data collected were bladder diaries, symptoms assessed with Urinary Symptom Profile (USP), bladder sensations with first desire to void (FDV) and strong desire to void (SDV) during the 20mL/min cystometry, and presence of DO. The volume between FDV and SDV was calculated (FDV-SDV).

RESULTS

Two hundred and two patients were included (mean age 47.4±11.8 years, median EDSS 3 IQR [2-5], 74.7% of women). DO was found in 104 (51.5%) patients. Reduced FDV-SDV volume (<50mL) was significantly associated with the occurrence of DO (27% vs. 5%; P<0.0001), and DO was associated with earlier sensations during cystometries (167±88mL vs. 204±109mL for FDV, P=0.02; 285±131mL vs. 353±116mL for SDV, P<0.001). In patients without DO, FDV-SDV volume was correlated with void frequency (rho=-0.30; P=0.03), mean voided volume (rho=0.52; P<0.001), and USP OAB sub-score (rho=0.32; P<0.01), especially with the item related to the warning time (rho=0.38; P<0.01).

CONCLUSION

DO has an impact on bladder sensations during cystometries in PwMS. In the absence of DO, a reduced FDV-SDV volume may have a significant impact on OAB severity, especially in reducing the warning time.

LEVEL OF EVIDENCE: 4

Sleep Disorders and Childhood Enuresis in Women with Overactive Bladder Syndrome: Cross-Sectional Study

INTRODUCTION AND HYPOTHESIS

Childhood enuresis may be associated with overactive bladder syndrome (OAB) in adulthood, which may contribute to sleep disorders. The objective was to compare the prevalence of childhood enuresis and sleep quality among women with and without OAB.

METHODS

This mixed study included women with and without OAB, who completed an online questionnaire covering sociodemographic, urinary data, and five validated instruments in Portuguese: the Pittsburgh Sleep Quality Index (PSQI-BR), the Epworth Sleepiness Scale, the Berlin Questionnaire (QB-BR), the Modified Fatigue Impact Scale (MFIS-BR), and the Incontinence Questionnaire Overactive Bladder (ICIQ-OAB).

RESULTS

A total of 172 women were included, 86 in each group (OAB and non-OAB). The OAB group showed a higher prevalence of childhood enuresis (52.3% vs 25.6%, p < 0.001), poorer sleep quality on the PSQI-BR (9.6 ± 4.1 vs 5.7 ± 3.1, p < 0.001), more individuals classified as high risk of obstructive sleep apnea by the QB-BR (34.9% vs 15.1%, p < 0.001), higher impact on fatigue assessed by the MFIS-BR (39.3 ± 21.8 vs 17.8 ± 17.2, p < 0.001), and more daytime sleepiness according to the Epworth Sleepiness Scale (10.9 ± 6.1 vs 8.7 ± 4.8, p = 0.014). Women with OAB were associated with poor sleep quality, fatigue, obstructive sleep apnea, and daytime sleepiness. Childhood enuresis was associated with a 2.96 times higher chance of developing OAB (OR = 2.96; 95% CI: 1.41-6.19; p = 0.004).

CONCLUSIONS

Overactive bladder was associated with a higher prevalence of childhood enuresis, diminished sleep quality, elevated risk of obstructive sleep apnea, heightened fatigue, and increased daytime sleepiness among women. OAB increases the risk of sleep disorders and childhood enuresis increases the chances of developing OAB.

Periaqueductal gray subregions connectivity and its association with micturition desire-awakening function

Existing literature strongly supports the idea that children with primary nocturnal enuresis (PNE) have brainstem abnormalities. However, the connection between pre-micturition arousal responses and brain functional connectivities is still not clearly defined. Our study investigated the correlation between the gradations of micturition desire-awakening (MDA) functionality and the functional connectivity of the midbrain periaqueductal gray (PAG), a pivotal brainstem hub implicated in the neural regulation of micturition in humans. Neuroimaging and behavioral data from 133 patients with PNE and 40 healthy children were acquired from functional magnetic resonance imaging (fMRI) and precise clinical observations, respectively. The whole-brain correlation analyses were undertaken to elucidate the complex connectivity patterns between the subregions of PAG and the cerebral cortex, with a focus on their correlation to the spectrum of MDA functionality. A positive correlation was identified between MDA dysfunction and the resting-state functional connectivity (RSFC) between the left ventrolateral periaqueductal gray (vlPAG) and the right temporal pole of the superior temporal gyrus. Conversely, a negative correlation was observed between MDA dysfunction and the RSFC of the right vlPAG with the right superior parietal lobule. Additionally, MDA dysfunction exhibited a negative association with the RSFC between the dorsomedial PAG (dmPAG) and the right inferior parietal lobule. These findings may indicate that the specific signal from a distended bladder is blocked in the PAG and its functional connectivity with the executive function, attention, and default mode networks, ultimately leading to impaired arousal and bladder control. This revelation underscores potential neural targets for future therapeutic interventions.

Brain Responses Difference between Sexes for Strong Desire to Void: A Functional Magnetic Resonance Imaging Study in Adults Based on Graph Theory

Background: The alternations of brain responses to a strong desire to void were unclear, and the gender differences under the strong desire to void remain controversial. The present study aims to identify the functional brain network's topologic property changes evoked by a strong desire to void in healthy male and female adults with synchronous urodynamics using a graph theory analysis. Methods: The bladders of eleven healthy males and eleven females were filled via a catheter using a specific infusion and withdrawal pattern. A resting-state functional magnetic resonance imaging (fMRI) was performed on the enrolled subjects, scanning under both the empty bladder and strong desire to void states. An automated anatomical labeling (AAL) atlas was used to identify the ninety cortical and subcortical regions. Pearson's correlation calculations were performed to establish a brain connection matrix. A paired t-test (p < 0.05) and Bonferroni correction were applied to identify the significant statistical differences in topological properties between the two states, including small-world network property parameters [gamma (γ) and lambda (λ)], characteristic path length (Lp), clustering coefficient (Cp), global efficiency (Eglob), local efficiency (Eloc), and regional nodal efficiency (Enodal). Results: The final data suggested that females and males had different brain response patterns to a strong desire to void, compared with an empty bladder state. Conclusions: More brain regions involving emotion, cognition, and social work were active in females, and males might obtain a better urinary continence via a compensatory mechanism.

Mental health problems, stressful life events and new-onset urinary incontinence in primary school-age children: a prospective cohort study

Emotional/behaviour problems and exposure to stressful life events are thought to contribute to new onset of urinary incontinence (UI) amongst children who have attained bladder control. However, very few prospective studies have examined these associations. We assessed whether mental health problems and stressful life events were associated with subsequent new onset in UI using multivariable logistic regression in a prospective UK cohort (n = 6408). Mothers provided information on their child's symptoms of common mental disorders (Development and Wellbeing Assessment, 7 years), stressful life events (7-8 years) and wetting (day and night, 9 years). There was strong evidence that separation anxiety symptoms were associated with new-onset UI in the fully adjusted model (OR (95% CI) = 2.08 (1.39, 3.13), p < 0.001). Social anxiety, attention-deficit hyperactivity disorder and oppositional defiant disorder symptoms were associated with new-onset UI, but these associations attenuated following adjustment for child developmental level and earlier emotional/behaviour problems. There was weak evidence for a sex interaction with stressful life events (p = 0.065), such that females experiencing more stressful life events were at higher risk of new-onset UI (fully adjusted model OR (95% CI) = 1.66 (1.05, 2.61), p = 0.029), but there was no association in males (fully adjusted model OR (95% CI) = 0.87 (0.52, 1.47), p = 0.608). These results suggest that separation anxiety and stressful life events in girls may lead to an increase in UI.

Prevalence of urinary incontinence and associated factors in nursing homes: a multicentre cross-sectional study

BACKGROUND

Urinary incontinence (UI) is a common geriatric syndrome with high health and socio-economic impacts in nursing home (NH) residents.

OBJECTIVES

To estimate the prevalence and types of UI and its associated factors in older people living in NHs in Central Catalonia (Spain). We also determined the proportion of residents who were receiving behavioural strategies to prevent/manage UI.

DESIGN AND SETTING

Cross-sectional study in 5 NHs conducted from January to March 2020.

METHODS

We included consenting residents aged 65 + permanently living in the NHs. Residents who were hospitalized, in a coma or palliative care were excluded. UI was assessed using Section H of the Minimum Data Set. Sociodemographic and health-related variables were examined. Descriptive, bivariate, and multivariate (logistic regression) analyses were performed.

RESULTS

We included 132 subjects (82.6% women), mean age of 85.2 (SD = 7.4) years. The prevalence of UI was 76.5% (95% CI: 68.60-82.93). The most common type was functional UI (45.5%), followed by urgency UI (11.4%). Only 46.2% of residents received at least one behavioural strategy to manage UI. Most sedentary behaviour (SB) variables presented a p-value lower than 0.001 in the bivariate analyses, but none remained in the final model. Moderate-severe cognitive impairment (OR = 4.44, p =.003), anticholinergic activity (OR = 3.50, p =.004) and risk of sarcopenia using SARC-F (OR = 2.75, p =.041) were associated with UI.

CONCLUSIONS

The prevalence of UI was high in this sample of NH residents compared to the literature, yet less than half received prompted voiding as a strategy to prevent/reduce UI.UI was associated with cognitive impairment, anticholinergic activity, and risk of sarcopenia.

Pathophysiology of Overactive Bladder and Pharmacologic Treatments Including β3-Adrenoceptor Agonists -Basic Research Perspectives

Overactive bladder (OAB) is a symptom-based syndrome defined by urinary urgency, frequency, and nocturia with or without urge incontinence. The causative pathology is diverse; including bladder outlet obstruction (BOO), bladder ischemia, aging, metabolic syndrome, psychological stress, affective disorder, urinary microbiome, localized and systemic inflammatory responses, etc. Several hypotheses have been suggested as mechanisms of OAB generation; among them, neurogenic, myogenic, and urothelial mechanisms are well-known hypotheses. Also, a series of local signals called autonomous myogenic contraction, micromotion, or afferent noises, which can occur during bladder filling, may be induced by the leak of acetylcholine (ACh) or urothelial release of adenosine triphosphate (ATP). They can be transmitted to the central nervous system through afferent fibers to trigger coordinated urgency-related detrusor contractions. Antimuscarinics, commonly known to induce smooth muscle relaxation by competitive blockage of muscarinic receptors in the parasympathetic postganglionic nerve, have a minimal effect on detrusor contraction within therapeutic doses. In fact, they have a predominant role in preventing signals in the afferent nerve transmission process. β3-adrenergic receptor (AR) agonists inhibit afferent signals by predominant inhibition of mechanosensitive Aδ-fibers in the normal bladder. However, in pathologic conditions such as spinal cord injury, it seems to inhibit capsaicin-sensitive C-fibers. Particularly, mirabegron, a β3-agonist, prevents ACh release in the BOO-induced detrusor overactivity model by parasympathetic prejunctional mechanisms. A recent study also revealed that vibegron may have 2 mechanisms of action: inhibition of ACh from cholinergic efferent nerves in the detrusor and afferent inhibition via urothelial β3-AR.

Increase in physiological inhibitory control results in better suppression of unwanted memories

Forgetting or suppressing a memory with unwanted content is just as important as remembering a desirable one. In addition to emphasizing the role of inhibitory control in memory suppression processes, neuropsychological studies have indicated that an intentional inhibition targeting a brain area may exert its inhibitory effects in seemingly unrelated areas through a common inhibitory network. In this study, we aimed to investigate whether the suppression of unwanted memories can be strengthened by recruiting an inhibitory task that can be simultaneously performed with a memory suppression task. Therefore, we manipulated the level of urinary urgency-induced inhibition of participants (N = 180) and test its effect on the suppression of unwanted memories using a Think/No-Think (T/NT) task. The results of our study indicated that individuals with high levels of urinary urgency demonstrated greater memory suppression compared to those with low urinary urgency. Findings and their implications are discussed within the context of cognitive and clinical perspectives, and recommendations are made for future research.

[Neurology meets Urology : Overview of urologically relevant neurological diseases]

In addition to the classical neurourological diseases multiple sclerosis and paraplegia/spina bifida, there are many and also widely spread diseases of the neurological spectrum that can result in significant dysfunctions of the urinary tract. Depending on the location (cerebral/suprapontine, spinal/suprasacral, spinal infrasacral and peripheral), different disorders can result (detrusor overactivity and underactivity, sphincter dyssynergia and low compliance). Changes can also occur over the course of an illness and thus make the analysis of the respective disorder even more difficult. Not all patients present directly to a neurourological center and in some cases the connection is not directly apparent. Firstly, this article focuses on the urological relevance of the respective neurological disease. Secondly, the basic neurourological information should support the initial assessment of the disorder.

Abnormal Resting-State Network Presence in Females with Overactive Bladder

Overactive bladder (OAB) is a global problem reducing the quality of life of patients and increasing the costs of any healthcare system. The etiology of OAB is understudied but likely involves supraspinal network alterations. Here, we characterized supraspinal resting-state functional connectivity in 12 OAB patients and 12 healthy controls (HC) who were younger than 60 years. Independent component analysis showed that OAB patients had a weaker presence of the salience (Cohen's d = 0.9) and default mode network (Cohen's d = 1.1) and weaker directed connectivity between the fronto-parietal network and salience network with a longer lag time compared to HC. A region of interest analysis demonstrated weaker connectivity in OAB compared to HC (Cohen's d > 1.6 or < -1.6), particularly within the frontal and prefrontal cortices. In addition, weaker seed (insula, ventrolateral prefrontal cortex) to voxel (anterior cingulate cortex, frontal gyrus, superior parietal lobe, cerebellum) connectivity was found in OAB compared to HC (Cohen's d > 1.9). The degree of deviation in supraspinal connectivity in OAB patients (relative to HC) appears to be an indicator of the severity of the lower urinary tract symptoms and an indication that such symptoms are directly related to functional supraspinal alterations. Thus, future OAB therapy options should also consider supraspinal targets, while neuroimaging techniques should be given more consideration in the quest for better phenotyping of OAB.

Updates of Overactive Bladder in Pediatrics

Overactive bladder (OAB) is clinically defined as urinary urgency with or without urinary incontinence. It is associated with daytime frequency or constipation and has a prevalence of approximately 5%-12% among 5- to 10-year-olds. The appropriate functional exchange between the pontine micturition center, periaqueductal gray matter, and prefrontal cortex is important for proper micturition control. Several studies on pediatric cases observed a link between OAB and neuropsychiatric problems, such as anxiety, depression, and attention deficit, and treatment of these comorbidities improved patient symptoms. In this review, we present the pathophysiology of OAB, its associated conditions, and aspects related to updates in OAB treatment, and we propose a step-by-step treatment approach following this sequence: behavioral therapy, medical treatment, and invasive treatment. Although anticholinergic drugs are the mainstay of OAB medical treatment, beta-3 agonists and alpha-blockers are now recommended as a result of significant advancements in pharmacologic treatment in the last 10 years. Electrical stimulation techniques and botulinum toxin are also effective and can be used, especially in conventional treatment-refractory cases.

Assessment of Brainstem Functional Organization in Healthy Adults and Overactive Bladder Patients Using Ultra-High Field fMRI

The pathophysiological mechanisms of overactive bladder syndrome (OAB) remain largely unknown, with major involvement of the central nervous system (CNS). The periaqueductal gray (PAG) is a brainstem area which is indicated to play an essential role in bidirectional communication between the bladder and the CNS. We aimed to assess consistency of PAG functional organization across different bladder sensory states in OAB patients. We propose, that PAG functional organization patterns across sensory states will differ between controls and OAB patients. We analyzed fMRI scans at 7 Tesla from six controls and two OAB patients. The Louvain module detection algorithm was applied to parcellate the PAG in empty and full bladder states. We assessed within-subject consistency and investigated differences in this consistency between both groups. High within-subject agreement of PAG parcellations between empty and full bladder states was demonstrated in both groups. Additionally, we showed that the correlations between PAG clusters in both bladder states were significantly different in patients compared to controls (p = 0.039). The methods introduced here offer a promising tool to assess functional organization of the PAG and understand the underlying pathology and the role of this region in OAB syndrome.

Anatomy, physiology, and evaluation: Bowel, bladder, and sexual disorders

Our present understanding of bowel and bladder control has changed dramatically with the introduction of functional imagining technologies such as PET, SPECT, fMRI scanning, and near-infrared spectroscopy of the brain. Urologists tend to see control of urination and defecation as processes that occurred at or below the level of the pons for the most part. In this chapter, we examine the control of storing and emptying of urine and stool from what will be a more neurocentric perspective, integrating the frontal lobes into the process and moving beyond the pons on which most of the literature has focused in the past. Utilizing this approach gives us a better understanding of why there is an overlapping of neuropsychiatric problems in many patients with voiding dysfunction.

Between-subject similarity of functional connectivity-based organization of the human periaqueductal gray related to autonomic processing

The periaqueductal gray (PAG) is a brain stem area designated to play an essential role in lower urinary tract (LUT) control. Post-mortem human and animal studies have indicated that the PAG is symmetrically organized in functionally and anatomically distinct columns which are involved in sympathetic or parasympathetic autonomic control of the LUT. The current study aims to find consistency across subjects and identify homologous clusters between subjects. Here, we evaluated data from 10 female participants. During a bladder filling protocol, we ran a resting-state functional magnetic resonance imaging (fMRI) scan while participants experienced a strong desire to void. A voxel-by-voxel correlation matrix of the PAG was created and parcellated using the Louvain module detection algorithm. Resulting in a map of the PAG in which each voxel is assigned to a cluster as determined by the Louvain module detection algorithm. The spatial similarity of resulting clusters between participants was assessed by computing the Dice similarity coefficient for all cluster comparisons. Next, we designed a permutation test to create randomized parcellation maps which enabled us to statistically test the similarity values observed across participants. We observed several significantly similar clusters between subjects compared to permutations (p ≤ 0.05). These results show that the PAG can be parcellated into distinct clusters which show a similar spatial distribution at the group level. This analysis is a crucial step to determine the agreement between in vivo PAG parcellations and the functional and anatomical columnar organization of the PAG which is known from previous research. These advancements may enable us to identify the relationship between LUT symptoms, such as urgency, and activity patterns in the PAG in normal and pathological states.

Abnormal resting-state functional connectivity of hippocampal subregions in children with primary nocturnal enuresis

Objective

Previous neuroimaging studies have shown abnormal brain-bladder control network in children with primary nocturnal enuresis (PNE). The hippocampus, which has long been considered to be an important nerve center for memory and emotion, has also been confirmed to be activating during micturition in several human imaging studies. However, few studies have explored hippocampus-related functional networks of PNE in children. In this study, the whole resting-state functional connectivity (RSFC) of hippocampus was investigated in children with PNE.

Methods

Functional magnetic resonance imaging data of 30 children with PNE and 29 matched healthy controls (HCs) were analyzed in our study. We used the seed-based RSFC method to evaluate the functional connectivity of hippocampal subregions defined according to the Human Brainnetome Atlas. Correlation analyses were also processed to investigate their relationship with disease duration time, bed-wetting frequency, and bladder volume.

Results

Compared with HCs, children with PNE showed abnormal RSFC of the left rostral hippocampus (rHipp) with right fusiform gyrus, right Rolandic operculum, left inferior parietal lobule, and right precentral gyrus, respectively. Moreover, decreased RSFC of the left caudal hippocampus (cHipp) with right fusiform gyrus and right supplementary motor area was discovered in the PNE group. There were no significant results in the right rHipp and cHipp seeds after multiple comparison corrections. In addition, disease duration time was negatively correlated with RSFC of the left rHipp with right Rolandic operculum (r = -0.386, p = 0.035, uncorrected) and the left cHipp with right fusiform gyrus (r = -0.483, p = 0.007, uncorrected) in the PNE group, respectively. In the Receiver Operating Characteristic (ROC) analysis, all the above results of RSFC achieved significant performance.

Conclusions

To our knowledge, this is the first attempt to examine the RSFC patterns of hippocampal subregions in children with PNE. These findings indicated that children with PNE have potential dysfunctions in the limbic network, sensorimotor network, default mode network, and frontoparietal network. These networks may become less efficient with disease duration time, inducing impairments in brain-bladder control, cognition, memory, and emotion. Further prospective research with dynamic observation of brain imaging, bladder function, cognition, memory, and emotion is warranted.

Functional brain imaging and central control of the bladder in health and disease

Central control of the bladder is a complex process. With the development of functional imaging technology and analysis methods, research on brain-bladder control has become more in-depth. Here, we review previous functional imaging studies and combine our latest findings to discuss brain regions related to bladder control, interactions between these regions, and brain networks, as well as changes in brain function in diseases such as urgency urinary incontinence, idiopathic overactive bladder, interstitial cystitis/bladder pain syndrome, urologic chronic pain syndrome, neurogenic overactive bladder, and nocturnal enuresis. Implicated brain regions include the pons, periaqueductal grey, thalamus, insula, prefrontal cortex, cingulate cortex, supplementary motor area, cerebellum, hypothalamus, basal ganglia, amygdala, and hippocampus. Because the brain is a complex information transmission and processing system, these regions do not work in isolation but through functional connections to form a number of subnetworks to achieve bladder control. In summarizing previous studies, we found changes in the brain functional connectivity networks related to bladder control in healthy subjects and patients involving the attentional network, central executive network or frontoparietal network, salience network, interoceptive network, default mode network, sensorimotor network, visual network, basal ganglia network, subcortical network, cerebella, and brainstem. We extend the working model proposed by Griffiths et al. from the brain network level, providing insights for current and future bladder-control research.

OAB supraspinal control network, transition with age, and effect of treatment: A systematic review

OBJECTIVE

In light of a better understanding of supraspinal control of nonneurogenic overactive bladder (OAB), the prevalence of which increases with age, functional imaging has gained significant momentum. The objective of this study was to perform a systematic review on the transition of supraspinal control of OAB with age, the effect of therapeutic modalities, and a coordinate-based meta-analysis of all neuroimaging evidence on supraspinal OAB control in response to bladder filling.

METHODOLOGY

We performed a systematic literature search of all relevant libraries in November 2021. The coordinates of brain activity were extracted from eligible neuroimaging studies to perform an activation likelihood estimation (ALE) meta-analysis.

RESULTS

A total of 16 studies out of 241 were selected for our systematic review. Coordinates were extracted from five experiments involving 70 patients. ALE meta-analysis showed activation of the insula, supplementary motor area, dorsolateral prefrontal cortex, anterior cingulate gyrus, and temporal gyrus with a transition of activation patterns with age, using a threshold of uncorrected p < 0.001. Among young patients, neuroplasticity allows the activation of accessory circuits to maintain continence, as in the cerebellum and temporoparietal lobes. Anticholinergics, pelvic floor muscle training, sacral neuromodulation, and hypnotherapy are correlated with supraspinal changes attributed to adaptability and possibly a substratum of an intrinsic supraspinal component. The latter is better demonstrated by a resting-state functional connectivity analysis, a promising tool to phenotype OAB with recent successful models of predicting severity and response to behavioral treatments.

CONCLUSION

Future neuroimaging studies are necessary to better define an OAB neurosignature to allocate patients to successful treatments.

Systematic review and meta-analysis: relationships between attention-deficit/hyperactivity disorder and urinary symptoms in children

Lower urinary tract symptoms (LUTS), e.g., urinary frequency, pressure, urgency, and overactive bladder syndrome, are commonly reported in children with attention-deficit/hyperactivity disorder (ADHD). Understanding the co-occurrence of these conditions has implications regarding clinical approaches, treatments, and improved quality of life. We conducted a systematic review and meta-analysis to examine the relationships between LUTS and ADHD in children. We searched for articles published between January 1990 and July 2019, in PubMed, CENTRAL, and PsycNet. Two authors independently screened all articles and extracted data. We performed random-effect meta-analyses for ADHD with pooled outcomes for LUTS. We identified 119 relevant articles in the literature and 18 articles fulfilled the inclusion criteria for the systematic review, of which, 5 articles had sufficient data for meta-analysis. Examining ADHD among individuals with LUTS, the odds ratio was 2.99 (95% CI 1.13, 7.88, p < 0.001), compared to controls. In multiple studies, the mean overall score for LUTS, using a standardized measure, was significantly higher in patients with ADHD in comparison to controls, and the severity of ADHD was positively associated with the severity of LUTS. Younger age in children was correlated with a higher LUTS score. Different subtypes of urinary incontinence demonstrated differences in behavioral problems and psychiatric comorbidity. Sex differences in LUTS were not consistent across articles. Our results indicate clinically significant associations between ADHD and LUTS in children. Because LUTS and ADHD are common disorders in children, clinicians should be aware of these associations as they inform optimal assessment and treatment strategies.

NIRS: Past, Present, and Future in Functional Urology

Purpose of Review

Near infrared spectroscopy (NIRS) is a non-invasive optical technique that uses near infrared light to detect the oxygenation status and hemodynamics of various organs. This article reviews the use of NIRS for the non-invasive assessment of lower urinary tract dysfunction (LUTD). Applications include assessment of bladder outlet obstruction, overactive and underactive bladder, neurogenic LUTD, pediatric LUTD, interstitial cystitis/bladder pain syndrome, and pelvic floor dysfunction. In addition, the article describes how NIRS is elucidating more about the brain-bladder connection. Technological advancements enabling these applications are also discussed.

Recent Findings

While evidence exists for the application of NIRS throughout a wide range of LUTD, most of these studies are limited by small sample sizes without matched controls. Investigators have experienced problems with reproducibility and motion artifacts contaminating the data. The literature is also becoming dated with use of older technology.

Summary

NIRS holds potential for the non-invasive acquisition of urodynamic information over time scales and activities not previously accessible, but it is not yet ready for use in routine clinical practice. Advances in wearable technology will address some of the current limitations of NIRS, but to realize its full potential, larger scale validation studies will be required. Moreover, multidisciplinary collaboration between clinicians, scientists, engineers, and patient advocates will be critical to further optimize these systems.

Overactive Bladder Symptoms Within Nervous System: A Focus on Etiology

Overactive bladder (OAB) is a common debilitating condition characterized by urgency symptoms with detrimental effects on the quality of life and survival. The exact etiology of OAB is still enigmatic, and none of therapeutic approaches seems curative. OAB is generally regarded as a separate syndrome, whereas in clinic, OAB symptoms could be found in numerous diseases of other non-urogenital systems, particularly nervous system. The OAB symptoms in neurological diseases are often poorly recognized and inadequately treated. This review provided a comprehensive overview of recent findings related to the neurogenic OAB symptoms. Relevant neurological diseases could be mainly divided into seven kinds as follows: multiple sclerosis and related neuroinflammatory disorders, Parkinson’s diseases, multiple system atrophy, spinal cord injury, dementia, peripheral neuropathy, and others. Concurrently, we also summarized the hypothetical reasonings and available animal models to elucidate the underlying mechanism of neurogenic OAB symptoms. This review highlighted the close association between OAB symptoms and neurological diseases and expanded the current knowledge of pathophysiological basis of OAB. This may increase the awareness of urological complaints in neurological disorders and inspire robust therapies with better outcomes.

EXPRESS: High Bladder Pressure Reduces the Ability to Filter Out Interference From Distractors in Low Perceptual Load Condition

According to the load theory of attention, an active cognitive control mechanism is needed to ensure that behavior is controlled by target-relevant information when distractors are also perceived. Although the active cognitive control mechanism consists of working memory, cognitive flexibility, and inhibition components, predictions regarding the load effects of this mechanism were derived mostly from studies on working memory. We aimed to test whether these predictions are also valid for an inhibition component. The inhibitory load was manipulated physiologically by creating different bladder pressure and its effects on distractor interference were examined under low and high perceptual load conditions. Results indicated that the availability of inhibitory control resources was important for decreasing the interference of distractors in the low perceptual load condition and that the high perceptual load reduced the effects of distractors independently from the availability of inhibitory resources. Results were consistent with the predictions of load theory, and to the best of our knowledge, the study provided the first piece of evidence in terms of the load effect of inhibition component on distractor interference.

Abnormal resting-state brain activity and connectivity of brain-bladder control network in overactive bladder syndrome

BACKGROUND

Neuroimaging studies have shown that the brain is involved in the mechanism of overactive bladder disease (OAB).

PURPOSE

To explorer spatial patterns of spontaneous neural activities and functional integration in patients with OAB.

MATERIAL AND METHODS

In total, 28 patients with OAB and 28 matched healthy controls (HC) underwent resting-state functional magnetic resonance imaging and completed questionnaires to assess clinical symptoms. The amplitude of low-frequency fluctuation (ALFF) and ROI-based functional connectivity (FC) within the brain-bladder control network (BBCN) were calculated and compared between the two groups using a two-sample t-test. Pearson correlation analysis was performed to investigate the relationship between ALFF and the clinical score of patients with OAB.

RESULTS

Compared with HCs, patients with OAB exhibited significantly decreased ALFF in the left superior medial middle gyrus (SFGmed) and superior dorsal frontal gyrus (SFGdor), and increased ALFF in the right hippocampus. Furthermore, ALFF values in the left SFGmed were negatively correlated with OABSS scores. FC in patients with OAB was significantly increased between the bilateral caudate nucleus (CAU) and bilateral SFGdor, the bilateral CAU and bilateral supplementary motor area (SMA), the bilateral thalamus and SMA; the left CAU and bilateral SFGmed, the left CAU and bilateral anterior cingulate gyrus, and the left CAU and left insula. Additionally, decreased FC was found between the bilateral amygdala and bilateral SFGmed and the left SMA and left insula.

CONCLUSION

These abnormal activities and connectivities of BBCN may indicate impaired cortical control of micturition in OAB, suggesting a possible neural mechanism of OAB.

Sophisticated regulation of micturition: review of basic neurourology

The neurological regulation of the lower urinary tract can be viewed separately from the perspective of sensory neurons and motor neurons. First, in the receptors of the bladder and urethra of sensory nerves, sensations are transmitted through the periaqueductal gray matter of the midbrain to the cerebral cortex, and the cerebrum goes through the process of decision-making. Motor neurons are divided into upper motor neurons (UMNs) and lower motor neurons (LMNs). UMNs coordinate storage and micturition in the brain stem so that synergic voiding can occur. LMNs facilitate muscle contractions in the spinal cord. The muscles involved in urinary storage and micturition are innervated by the somatic branches of sympathetic, parasympathetic, and peripheral nerves. Sympathetic nerves are responsible for contractions of urethral smooth muscles, while parasympathetic nerves originate from S2–S4 and are in charge of contractions of the bladder muscle. Somatic nerves originate from the motor neurons in Onuf’s nucleus, which is a specific part of somatic nerves. In this review, we will investigate the structures of the nervous systems related to the lower urinary tract and the regulatory system of innervation for the urinary storage and micturition and discuss the clinical significance and future prospects of neurourological research.

Change in the central control of the bladder function of rats with focal cerebral infarction induced by photochemically-induced thrombosis

The photochemically-induced thrombosis (photothrombosis) method can create focal cerebral infarcts anywhere in the relatively superficial layers of the cerebrum; it is easy to implement and minimally invasive. Taking advantage of this versatility, we aimed to establish a new rat model of urinary frequency with focal cerebral infarction, which was characterized by its simplicity, nonlethal nature, and high reproducibility. The prefrontal cortex and the anterior cingulate cortex, which are involved in lower urinary tract control, were targeted for focal cerebral infarction, and urinary parameters were measured by cystometrogram. Cystometric analysis indicated that micturition intervals significantly shortened in photothrombosis-treated rats compared with those in the sham operative group on Days 1 and 7 (P < 0.01), but prolonged after 14 days, with no difference between the two groups. Immunopathological evaluation showed an accumulation of activated microglia, followed by an increase in reactive astrocytes at the peri-infarct zone after photothrombotic stroke. Throughout this study, all postphotothrombosis rats showed cerebral infarction in the prefrontal cortex and anterior cingulate cortex; there were no cases of rats with fatal cerebral infarction. This model corresponded to the clinical presentation, in that the micturition status changed after stroke. In conclusion, this novel model combining nonlethality and high reproducibility may be a suitable model of urinary frequency after focal cerebral infarction.

Characterizing the cortical pathways underlying visual trigger induced urinary urgency incontinence by functional MRI

AIMS

Visual triggers have long been recognized clinically to stimulate urgency urinary incontinence (UUI). Current pathophysiology recognizes the importance of cortical control over micturition but there is no standardized methodology for clinicians to study the impact of visual triggers. Our aim was to develop an imaging protocol able to characterize the brain's response to personalized visual triggers, providing a methodology for evaluation on connectivity within the brain in patients with visually triggered urinary urgency.

METHODS

A magnetic resonance imaging (MRI) methodology specific for urologic use was developed. A 3T-Elition Scanner was first used to acquire static structural images. These images were then used to define approximately 200 brain regions of interest (ROI) using a validated brain atlas. Then, real-time functional MRI (fMRI) scans were conducted during natural bladder filling, where study subjects were shown randomized block sequences of visual stimuli comprised of both subject-specific trigger images and neutral images. The fMRI scan data were merged to identify key ROI underlying UUI.

RESULTS

Dynamic fMRI scans were conducted in 10 subjects, 4 with trigger-induced UUI, 2 with trigger-induced urgency, and 4 with no urgency or leakage to visual triggers. No subjects with UUI history lost continence during imaging, but all four subjects reported sensations of urgency in response to their own subject-specific trigger images. The ROI identified were the periaqueductal gray, anterior cingulate gyrus, pons, and prefrontal cortex. We found increased activity in the prefrontal cortex and limbic system ROI in response to subject-specific visual triggers of UUI.

CONCLUSIONS

This information provides proof of principle for further exploration of subject-specific trigger image evaluation using fMRI to explore causation in patients with UUI.

Future generation of combined multimodal approach to treat brain glioblastoma multiforme and potential impact on micturition control

Glioblastoma remains lethal even when treated with standard therapy. This review aims to outline the recent development of various advanced therapeutics for glioblastoma and briefly discuss the potential impact of glioblastoma and some of its therapeutic approaches on the neurological function micturition control. Although immunotherapy led to success in treating hematological malignancies, but no similar success occurred in treatment for brain glioblastoma. Neither regenerative medicine nor stem cell therapy led to astounding success in glioblastoma. However, CRISPR Cas system holds potential in multiple applications due to its capacity to knock-in and knock-out genes, modify immune cells and cell receptors, which will enable it to address clinical challenges in immunotherapy such as CAR-T and regenerative therapy for brain glioblastoma, improving the precision and safety of these approaches. The studies mentioned in this review could indicate that glioblastoma is a malignant disease with multiple sophisticated barriers to be overcome and more challenges might arise in the attempt of researchers to yield a successful cure. A multimodal approach of future generation of refined and safe therapeutics derived from CRISPR Cas therapeutics, immunotherapy, and regenerative therapeutics mentioned in this review might prolong survival or even contribute towards a potential cure for glioblastoma.

The innervation of the bladder, the pelvic floor, and emotion: A review

The innervation of the pelvic region is complex and includes extensive neurologic pathways. The higher centres' organisation determining the pelvic floor and organs' function remains a challenge understanding the physiological and pain mechanisms. Psychological and emotional factors have a profound influence on the pelvic floor and organ dysfunction such as LUTS. LUTS are associated with stress, depression, and anxiety. Neuroception is a subconscious neuronal system for detecting threats and safety and might explain the permanent disturbance of higher brain centres maintaining functional urological and gastrointestinal disorders and sphincter dysfunction.

Considering non-bladder aetiologies of overactive bladder: a functional neuroimaging study

OBJECTIVES

To better understand the neuropathophysiology of overactive bladder (OAB) in women by characterising supraspinal activity in response to bladder distention and cold stimulation.

SUBJECTS/PATIENTS AND METHODS

We recruited 24 female participants, 12 with OAB (median [interquartile range, IQR] age 40 [32-42] years) and 12 healthy controls (HCs) without lower urinary tract (LUT) symptoms (median [IQR] age 34 [28-44] years), and assessed LUT and cognitive function through neuro-urological examination, 3-day bladder diary, urodynamic investigation, and questionnaires. Functional magnetic resonance (MR) imaging using a 3-T scanner was performed in all participants during automated, repetitive bladder filling and draining (block design) with 100 mL body temperature (37 °C) saline using a MR-compatible and MR-synchronised infusion-drainage device until strong desire to void (HIGH-FILLING/DRAINING) and bladder filling with cold saline (4 °C, i.e. COLD). Whole-brain and region-of-interest analyses were conducted using Statistical Parametric Mapping, version 12.

RESULTS

Significant between-group differences were found for 3-day bladder diary variables (i.e. voiding frequency/24 h, P < 0.001; voided volume/void, P = 0.04; and urinary incontinence [UI] episodes/24 h, P = 0.007), questionnaire scores (International Consultation on Incontinence Questionnaire-Female LUT symptoms [overall, filling, and UI scores, all P < 0.001]; the Overactive Bladder Questionnaire short form [symptoms and quality-of-life scores, both P < 0.001]; the Hospital Anxiety and Depression Scale [anxiety P = 0.004 and depression P = 0.003 scores]), as well as urodynamic variables (strong desire to void, P = 0.02; maximum cystometric capacity, P = 0.007; and presence of detrusor overactivity, P = 0.002). Age, weight and cognitive function (i.e. Mini-Mental State Examination, P = 1.0) were similar between groups (P > 0.05). In patients with OAB, the HIGH task elicited activity in the superior temporal gyrus, ventrolateral prefrontal cortex (VLPFC), and mid-cingulate cortex; and the COLD task elicited activity in the VLPFC, cerebellum, and basal ganglia. Compared to HCs, patients with OAB showed significantly stronger cerebellar activity during HIGH-FILLING and significantly less activity in the insula and VLPFC during HIGH-DRAINING.

CONCLUSIONS

The present findings suggest a sensory processing and modulation deficiency in our OAB group, probably as part of their underlying pathophysiology, as they lacked activity in essential sensory processing areas, such as the insula. Instead, accessory areas, such as the cerebellum, showed significantly stronger activation compared to HCs, presumably supporting pelvic-floor motor activity to prevent UI. The novel findings of the present study provide physiological evidence of the necessity to consider non-bladder aetiologies of bladder symptoms.

Regional Cerebral Cortical Atrophy is Related to Urinary Tract Symptoms in Parkinson's Disease

BACKGROUND AND PURPOSE

Lower urinary tract symptoms (LUTS) are the most common nonmotor symptoms usually occurring mid-stage of Parkinson's disease (PD); however, its underlying mechanisms are unknown. We aimed to assess whether corticometry or volumetry can identify a pattern of cerebral cortical changes in PD patients with LUTS.

METHODS

We recruited 85 idiopathic PD patients and performed corticometry and volumetry on various cortical regions using each patient's magnetic resonance imaging. To identify a correlation between the cortical thickness/volume and nonmotor symptoms scale domain 7 scores, which represent the severity of LUTS, we performed general linear model and region of interest analyses.

RESULTS

Significant regional thinning of the left precuneus, left temporal pole, left precentral, right precuneus, and right pars opercularis was correlated with nonmotor symptoms scale domain 7 scores. We also found that cortical volumes of left precuneus and left frontal pole were inversely correlated with the severity of urinary symptoms.

CONCLUSIONS

This study showed that the thicknesses and volumes of several cortical regions were significantly correlated with the severity of LUTS in PD patients. The findings of regional atrophy and thinning of specific cortical regions in this study provide additional evidence that multiple cortical regions, especially the precuneus cortex, not only may be involved in urinary dysfunctions of PD patients but also may help to elucidate the exact underlying mechanisms for LUTS in PD patients.

Baseline Brain Segmental Volumes in Responders and Nonresponders to Anticholinergic Therapy for Overactive Bladder Syndrome

OBJECTIVE

Evaluate structural differences in brains of responders (R) and nonresponders (NR) to anticholinergic (AC) therapy for overactive bladder (OAB).

MATERIALS AND METHODS

This was a retrospective cohort study of age matched women treated with an AC medication for OAB and underwent magnetic resonance imaging within 12 months before treatment. Data on pretreatment demographic and clinical variables and symptom severity was also collected.T1-weighted magnetic resonance images of the brain for each subject were segmented using FreeSurfer software. Structures included for analysis were cerebral cortex, white matter, subcortical gray matter, cerebellum, and brain stem.Nonresponders were defined as patients who reported less than 50% improvement after a minimum of 4 weeks on the maximum dose of the prescribed medication. Pairwise analysis between groups was performed using the Wilcoxon-Rank Sum test and Fisher exact test where appropriate. Spearman ρ was used to evaluate for correlations between neurologic structures and symptom severity.

RESULTS

There were no differences in pretreatment characteristics or symptom severity between the 21 R and 18 NR. Nonresponders had lower volumes of the right caudal anterior cingulate gyrus white matter (1919 mm3 vs 2416 mm3, P = 0.008) and right parahippocampal gyrus white matter (1008 mm3 vs 1469 mm3, P = 0.001). Incontinence episode frequency showed a negative moderate correlation with the anterior cingulate gyrus white matter volume (ρ = -0.4228, P = 0.007). The right and left cerebellar cortices showed weak and moderate negative correlations to frequency of nocturia (ρ = -0.384, P = 0.02 and ρ -0.443, P = 0.005, respectively).

CONCLUSION

There are measurable volumetric differences in brain structures in R and NR to AC therapy.

Responses of functional brain networks to bladder control in healthy adults: a study using regional homogeneity combined with independent component analysis methods

OBJECTIVE

A functional magnetic resonance imaging (fMRI) study was performed during urodynamic examination in healthy adults to determine the responses of functional brain networks to bladder control during urine storage.

METHODS

The brain imaging was performed in empty and full bladder states during urodynamic examination. First, we used independent component analysis (ICA) to obtain several resting state network masks, then the brain regions with significantly different regional homogeneity (ReHo) values between the two states were determined using a paired t test (p < 0.05; Gaussian random field correction [GRF]: voxel p < 0.01 and cluster p < 0.05) and presented in their corresponding resting state network (RSN) masks.

RESULTS

Data sets obtained from the remaining 20 subjects were analyzed after motion correction. Nine RSNs were identified by group-ICA, including the salience network (SN), default mode network (DMN), central executive network (CEN), dorsal attention network (dAN), auditory network (AN), sensorimotor network (SMN), language network (LN), visual network (VN), and cerebellum network (CN). The ReHo values were significantly increased (p < 0.05, GRF corrected) within the SN, DMN, and CEN in the full bladder state compared with the empty bladder state.

CONCLUSION

Significant changes within the three functional brain networks were demonstrated when the bladder was full, suggesting that SN provides bladder sensation and DMN may provide self-reference, self-reflection, and decision-making about whether to void after assessment of the external environment, while CEN may provide support related to episodic memory, which provides new insight into the processing of bladder control and could serve as a premise to further explore the pathologic process underlying bladder dysfunction.

Parcellation of human periaqueductal gray at 7-T fMRI in full and empty bladder state: The foundation to study dynamic connectivity changes related to lower urinary tract functioning

Aims

The periaqueductal gray (PAG) is a brain stem area involved in processing signals related to urine storage and voiding. The PAG is proposed to be responsible for projecting afferent information from the bladder to cortical and subcortical brain areas and acts as a relay station projecting efferent information from cortical and subcortical areas to the pons and spinal cord. Here, we use 7‐Tesla functional magnetic resonance imaging to parcellate the PAG into functionally distinct clusters during a bladder filling protocol.

Methods

We assess the similarity between parcellation results in empty and full bladder states and show how these parcellations can be used to create dynamic response profiles of connectivity changes between clusters as a function of bladder sensations.

Results

For each of our six healthy female participants, we found that the agreement between at least one of the clusters in both states resulting from the parcellation procedure was higher than could be expected based on chance (p ≤ .05), and observed that these clusters are significantly organized in a symmetrical lateralized fashion (p ≤ .05). Correlations between clusters change significantly as a function of experienced sensations during bladder filling (p ≤ .05).

Conclusions

This opens new possibilities to investigate the effects of treatments of lower urinary tract symptoms on signal processing in the PAG, as well as the investigation of disease‐specific bladder filling related dynamic signal processing in this small brain structure.

[A case of oculomotor disorder and urinary retention due to a lower midbrain lesion]

We report an 86-year-old woman who suffered sudden onset of diplopia while cooking. The patient presented with binocular diplopia, bilateral adduction weakness, convergence disorder and bilateral abduction nystagmus. Although brain MRI on admission detected no abnormality, a repeat MRI examination on the following day demonstrated a focal hyperintense lesion in the tegmentum of the midbrain on diffusion-weighted images. At 36 hours after admission, lower abdominal distension became apparent, and about 1 liter of urine was drained via a urethral catheter. Bladder filling sensation was not present, and we considered that the midbrain lesion had been responsible for the oculomotor disorder and urinary retention. As cerebral infarction was the most likely pathology of this lesion, an antiplatelet agent was administered. At two months after onset, the eye movement disorder was resolved and there was no diplopia. Bladder voiding also resumed at normal intervals. We considered that the bilateral medial longitudinal fasciculi and subgroups of the oculomotor nucleus, which contain motor neurons supplying the medial rectus muscle, had been responsible for the oculomotor disorder. The urinary retention was thought to have been caused by a lesion in the periaqueductal gray, which is one structure controlling micturition. This was a rare case of urinary retention due to a small midbrain infarction.

Regional brain atrophy in overactive bladder syndrome: a voxel based morphometry study

OBJECTIVES

To investigate whether patients with overactive bladder syndrome (OAB) have brain volume changes using voxel-based morphometry (VBM) and correlations with clinical tests.

METHODS

With institutional review board approval and after obtaining written informed consent, structural magnetic resonance imaging data were prospectively acquired in 28 patients and 28 control subjects. OAB symptoms were assessed using the OAB symptom score (OABSS) scale. The gray matter volume (GMV) of each voxel was compared between the two groups while controlling for the effects of age, sex, and education level. Correlation analysis was performed to identify correlations between abnormal GMV regions and OABSS scores in patients. Multiple comparisons were corrected using a false discovery rate (FDR) method.

RESULTS

Patients with OAB exhibited a GMV reduction in the right cerebellum, bilateral hippocampus, left insula, right superior temporal gyrus, left anterior cingulate gyrus, bilateral caudate nucleus and right middle frontal gyrus. Furthermore, there was a significant negative correlation between the local GMV of the right cerebellar hemisphere and OABSS score.

CONCLUSIONS

Patients with OAB have abnormal GMV in brain regions localized within the brain-bladder control network. It deepens our understanding of the structural changes in the brain area of the network. The patterns of structural reorganization in patients with OAB may provide useful information in the neuropathological mechanisms of the OAB.

Brain functional network alterations caused by a strong desire to void in healthy adults: a graph theory analysis study

PURPOSE

This resting-state functional magnetic resonance imaging (fMRI) study determined the functional connectivity (FC) changes and topologic property alterations of the brain functional network provoked by a strong desire to void in healthy adults using a graph theory analysis (GTA).

MATERIALS AND METHODS

Thirty-four healthy, right-handed subjects filled their bladders by drinking water. The subjects were scanned under an empty bladder and a strong desire to void states. The Pearson's correlation coefficients were calculated among 90 brain regions in the automated anatomical labeling (AAL) atlas to construct the brain functional network. A paired t test (P < .05, after false discovery rate [FDR] correction) was used to detect significant differences in the FC, topologic properties (small-world parameters [gamma, sigma], C_p, L_p, E_glob, E_loc, and E_nodal) between the two states in all subjects.

RESULTS

Both the two states showed small-world network properties. The clustering coefficient (C_p) and local efficiency (E_loc) in the whole brain network decreased, while the FC within the default mode network (DMN) increased during the strong desire to void compared with the empty bladder state. Moreover, an increased nodal efficiency (E_nodal) was detected in the basal ganglia (BG), DMN, sensorimotor-related network (SMN), and visual network (VN).

CONCLUSION

We detected FC changes and topologic property alterations in brain functional networks caused by a strong desire to void in healthy and suggest that the micturition control may be a process dominated by DMN and coordinated by multiple sub-networks (such as, BG, SMN, and VN), which could serve as a baseline for understanding the pathologic process underlying bladder dysfunction and be useful to improve targeted therapy in the future.

Identification of Normal Pressure Hydrocephalus by Disease-Specific Patterns of Brain Stiffness and Damping Ratio

OBJECTIVES

The aim of this study was to perform a whole-brain analysis of alterations in brain mechanical properties due to normal pressure hydrocephalus (NPH).

MATERIALS AND METHODS

Magnetic resonance elastography (MRE) examinations were performed on 85 participants, including 44 cognitively unimpaired controls, 33 with NPH, and 8 who were amyloid-positive with Alzheimer clinical syndrome. A custom neural network inversion was used to estimate stiffness and damping ratio from patches of displacement data, accounting for edges by training the network to estimate the mechanical properties in the presence of missing data. This learned inversion was first compared with a standard analytical approach in simulation experiments and then applied to the in vivo MRE measurements. The effect of NPH on the mechanical properties was then assessed by voxel-wise modeling of the stiffness and damping ratio maps. Finally, a pattern analysis was performed on each individual's mechanical property maps by computing the correlation between each person's maps with the expected NPH effect. These features were used to fit a classifier and assess diagnostic accuracy.

RESULTS

The voxel-wise analysis of the in vivo mechanical property maps revealed a unique pattern in participants with NPH, including a concentric pattern of stiffening near the dural surface and softening near the ventricles, as well as decreased damping ratio predominantly in superior regions of the white matter (family-wise error corrected P < 0.05 at cluster level). The pattern of viscoelastic changes in each participant predicted NPH status in this cohort, separating participants with NPH from the control and the amyloid-positive with Alzheimer clinical syndrome groups, with areas under the receiver operating characteristic curve of 0.999 and 1, respectively.

CONCLUSIONS

This study provides motivation for further development of the neural network inversion framework and demonstrates the potential of MRE as a novel tool to diagnose NPH and provide a window into its pathogenesis.

Effect of a strong desire to void on walking speed in individuals with multiple sclerosis and urinary disorders

BACKGROUND

Lower urinary tract symptoms, especially overactive bladder, are frequent and disabling in individuals with multiple sclerosis (IwMS). An association with gait disorders is common, which could aggravate continence difficulties and affect quality of life. The association between the need to void and walking has never been studied in this population.

OBJECTIVE

The primary aim of this study was to assess the effect of a strong desire to void (SDV) on walking speed in IwMS and lower urinary tract symptoms. The secondary aim was to identify clinical or urodynamic factors associated with walking speed impairment at SDV in this population.

METHODS

We included IwMS with urinary disorders and Expanded Disability Status Scale score<7 in this observational study. Individuals underwent 3 10-m walk tests (10MWT) and one Timed Up and Go (TUG) test at SDV and at post-void (PV).

RESULTS

Among the 72 IwMS included (mean [SD] age 50.6 [11.6] years; 46 [64%] females), the mean (SD) speed for 10MWT was 1.00 (0.31) m.s^-1 at SDV and 1.07 (0.30) m.s^-1 at PV (P<0.0001). Time for TUG was also increased when individuals felt SDV: mean 11.53 (4.6) sec at SDV versus 10.77 (3.8) sec at PV (P=0.004). No predictors of greater impairment of walking speed at SDV were identified.

CONCLUSION

This study suggests a clinical impact of bladder sensation on walking speed in IwMS and urinary disorders. None of the individual characteristics could predict greater decrease in gait velocity at SDV.

Brain dynamics and connectivity networks under natural auditory stimulation

The analysis of functional magnetic resonance imaging (fMRI) data is challenging when subjects are under exposure to natural sensory stimulation. In this study, a two-stage approach was developed to enable the identification of connectivity networks involved in the processing of information in the brain under natural sensory stimulation. In the first stage, the degree of concordance between the results of inter-subject and intra-subject correlation analyses is assessed statistically. The microstructurally (i.e., cytoarchitectonically) defined brain areas are designated either as concordant in which the results of both correlation analyses are in agreement, or as discordant in which one analysis method shows a higher proportion of supra-threshold voxels than does the other. In the second stage, connectivity networks are identified using the time courses of supra-threshold voxels in brain areas contingent upon the classifications derived in the first stage. In an empirical study, fMRI data were collected from 40 young adults (19 males, average age 22.76 ± 3.25), who underwent auditory stimulation involving sound clips of human voices and animal vocalizations under two operational conditions (i.e., eyes-closed and eyes-open). The operational conditions were designed to assess confounding effects due to auditory instructions or visual perception. The proposed two-stage analysis demonstrated that stress modulation (affective) and language networks in the limbic and cortical structures were respectively engaged during sound stimulation, and presented considerable variability among subjects. The network involved in regulating visuomotor control was sensitive to the eyes-open instruction, and presented only small variations among subjects. A high degree of concordance was observed between the two analyses in the primary auditory cortex which was highly sensitive to the pitch of sound clips. Our results have indicated that brain areas can be identified as concordant or discordant based on the two correlation analyses. This may further facilitate the search for connectivity networks involved in the processing of information under natural sensory stimulation.

Mindfulness-Based Stress Reduction Versus a Health Enhancement Program in the Treatment of Urge Urinary Incontinence in Older Adult Women: A Randomized Controlled Feasibility Study

Current treatment practices for older adult women with urge urinary incontinence (UUI) remain insufficient and ineffective. A randomized controlled feasibility trial was developed to evaluate three determinants of research feasibility and three determinants of intervention feasibility when comparing mindfulness-based stress reduction (MBSR) with a health enhancement program (HEP) in older adult women with UUI. Participants were recruited from the university health system, county senior centers, and community sites. Twenty-five postmenopausal women (mean age = 74 years) were randomized into MBSR treatment conditions or HEP comparison conditions for an 8-week intervention. Participants remained blinded to conditions. Research feasibility determinants were measured as recruitment, retention, and treatment delivery; intervention feasibility determinants were measured as acceptability, tolerability, and client receipt/enactment. Feasibility determinants established in the research literature as essential to intervention evaluation were recorded and evaluated throughout the current study. All six feasibility determinants confirmed positive results in the enrolled population. The use of MBSR and HEP as the active comparison to treat UUI in older adult women proved feasible in this trial. The results warrant the design of a larger-scale, multisite trial to study the efficacy of MBSR in treating UUI in older adult women.

TARGETS

Older adult women with high incidence of UUI.

INTERVENTION DESCRIPTION

MBSR treatment conditions or HEP comparison conditions.

MECHANISMS OF ACTION

Research and intervention feasibility determinants.

OUTCOMES

The use of MBSR and HEP as the active comparison to treat UUI in older adult women proved feasible in this trial. [ Research in Gerontological Nursing, 12(6), 285-297.].

Electrocorticographic Activity of the Brain During Micturition

Current therapies for neurogenic bladder do not allow spinal cord injury patients to regain conscious control of urine storage or voiding. Novel neural technologies may provide means to improve or restore the connection between the brain and the bladder; however, the specific brain areas and their underlying neural activities responsible for micturition must be better understood in order to design such technologies. In this retrospective study, we analyzed electrocorticographic (ECoG) data obtained from epilepsy patients who underwent ECoG grid implantation for epilepsy surgery evaluation, in the hopes of determining specific electrophysiological activity associated with micturition. Our results indicate modulation of the delta (δ, 0.1-4 Hz) and low-gamma (\gamma, 25-50 Hz) activity in the peri-Sylvian area and the inferior temporal lobe. These findings suggest involvement of the insular cortex and the uncinate fasciculus in micturition, important structures related to sensation and decision making. To date, this is the first known study utilizing ECoG data to elucidate the electrophysiological activity of the brain associated with bladder control and sensation.

Spontaneous Activity and the Urinary Bladder

The urinary bladder has two functions: to store urine, when it is relaxed and highly compliant; and void its contents, when intravesical pressure rises due to co-ordinated contraction of detrusor smooth muscle in the bladder wall. Superimposed on this description are two observations: (1) the normal, relaxed bladder develops small transient increases of intravesical pressure, mirrored by local bladder wall movements; (2) pathological, larger pressure variations (detrusor overactivity) can occur that may cause involuntary urine loss and/or detrusor overactivity. Characterisation of these spontaneous contractions is important to understand: how normal bladder compliance is maintained during filling; and the pathophysiology of detrusor overactivity. Consideration of how spontaneous contractions originate should include the structural complexity of the bladder wall. Detrusor smooth muscle layer is overlain by a mucosa, itself a complex structure of urothelium and a lamina propria containing sensory nerves, micro-vasculature, interstitial cells and diffuse muscular elements.Several theories, not mutually exclusive, have been advanced for the origin of spontaneous contractions. These include intrinsic rhythmicity of detrusor muscle; modulation by non-muscular pacemaking cells in the bladder wall; motor input to detrusor by autonomic nerves; regulation of detrusor muscle excitability and contractility by the adjacent mucosa and spontaneous contraction of elements of the lamina propria. This chapter will consider evidence for each theory in both normal and overactive bladder and how their significance may vary during ageing and development. Further understanding of these mechanisms may also identify novel drug targets to ameliorate the clinical consequences of large contractions associated with detrusor overactivity.

Bladder sensations in male and female overactive bladder patients compared to healthy volunteers: a sensation-related bladder diary evaluation

Objectives: To investigate the differences in bladder sensations of overactive bladder (OAB) patients compared to healthy volunteers. In addition, to see if bladder sensations are different in men and women.Methods: In a prospective, longitudinal study (METC 09-2-095), 66 volunteers and 68 OAB patients were included. Anticholinergic medication was stopped. Subjects filled out a sensation-related bladder diary (SR-BD), for two periods of 3 days, including a 4-points urgency scale and visual analogue scale for perception of bladder fullness.Results: In total, 6160 voids were assessed. Patients voided more often with higher degrees of urge at a lower mean voided volume (193 vs 270 ml/void; p < 0.001) than healthy volunteers. The mean urinary frequency per litre diuresis was also higher (5.8 vs 4.1/l; p < 0.001) in patients. At the same voided volume: patients perceived a higher mean bladder fullness, independent of the degree of urge, and higher urgency (1.4 vs 0.5/100 ml; p < 0.001) than healthy volunteers. There were no gender differences in the above-mentioned voiding parameters, except for the mean voided volume at urge 3 in volunteers (340 ml in men vs 362 ml in women; p = 0.03) and urge 1 in patients (171 ml in men vs 135 ml in women; p = 0.027).Conclusions: Bladder sensations were significantly increased in everyday life for both male and female OAB patients compared to healthy volunteers. OAB patients experienced a higher mean bladder fullness sensation, independent of the degree of urge, and higher mean urge/urgency at the same voided volume than volunteers. Bladder sensations are crucial in the assessment of treatment response.

Abnormal neural responses to emotional stimuli in children with primary monosymptomatic nocturnal enuresis

Nocturnal enuresis (NE) is a common disorder in school-aged children that has been reported to affect nearly 10% of 7-year-old children and affects both the children and their families. Previous studies have shown that the risk of psychosocial difficulties in children with enuresis is elevated. Thus, children with NE may experience negative effects on psychosocial health or emotion processing. Therefore, the aim of this study was to investigate the potential disturbance in emotional processing in children with NE using functional magnetic resonance imaging (fMRI). In this work, we used fMRI and an affective picture task to evaluate brain response changes in children with NE. Two groups, one consisting of 22 children with primary monosymptomatic NE and one with 23 healthy controls, were scanned using fMRI. Compared to the healthy subjects, children with NE mainly showed increased activation when viewing negative vs. neutral pictures in the bilateral medial superior frontal gyrus that extended to the anterior cingulate cortex. Our results demonstrated that children with primary monosymptomatic NE showed abnormal neural responses to emotional stimuli and overactivation in the medial prefrontal and anterior cingulate cortices suggested that children with primary monosymptomatic NE may be hypersensitive in their sensory perception of negative pictures.

Connectivity of the human insula: A cortico-cortical evoked potential (CCEP) study

OBJECTIVE

The human insula is increasingly being implicated as a multimodal functional network hub involved in a large variety of complex functions. Due to its inconspicuous location and highly vascular anatomy, it has historically been difficult to study. Cortico-cortical evoked potentials (CCEPs), utilize low frequency stimulation to map cerebral networks. They were used to study connections of the human insula.

METHODS

CCEP data was acquired from each sub-region of the dominant and non-dominant insula in 30 patients who underwent stereo-EEG. Connectivity strength to the various cortical regions was obtained via a measure of root mean square (RMS), calculated from each gyrus of the insula and ranked into weighted means.

RESULTS

The results of all cumulative CCEP responses for each individual gyrus were represented by circro plots. Forty-nine individual CCEP pairs were stimulated across all the gyri from the right and left insula. In brief, the left insula contributed more greatly to language areas. Sensory function, pain, saliency processing and vestibular function were more heavily implicated from the right insula. Connections to the primary auditory cortex arose from both insula regions. Both posterior insula regions showed significant contralateral connectivity. Ipsilateral mesial temporal connections were seen from both insula regions. In visual function, we further report the novel finding of a direct connection between the right posterior insula and left visual cortex.

SIGNIFICANCE

The insula is a major multi-modal network hub with the cerebral cortex having major roles in language, sensation, auditory, visual, limbic and vestibular functions as well as saliency processing. In temporal lobe epilepsy surgery failure, the insula may be implicated as an extra temporal cause, due to the strong mesial temporal connectivity findings.

Intra- and inter-resting-state networks abnormalities in overactive bladder syndrome patients: an independent component analysis of resting-state fMRI

PURPOSE

This study aims to determine whether intra-network and inter-network brain connectivities are altered using an independent component analysis (ICA).

METHODS

Resting-state functional MRI (rs-fMRI) data were acquired from 26 patients with OAB and 28 healthy controls (HC). Eleven resting-state networks (RSNs) were identified via ICA. General linear model (GLM) was used to compare intra-network FC and inter-network FC of RSNs between the two groups. Pearson correlation analyses were performed to investigate the relationship between the identified RSNs and clinical variables.

RESULTS

Compared with HC, the OAB group showed abnormal FC within the sensorimotor-related network (SMN), the dorsal attention network (DAN), the dorsal visual network (dVN), and the left frontoparietal network (LFPN). With respect to inter-network interactions, decreased FC was detected between the SMN and the anterior default mode network (aDMN).

CONCLUSION

This study demonstrated that abnormal FC between RSNs may reflect the altered resting state of the brain-bladder network. The findings of this study provide complementary evidence that can help further understand the neural substrates of the overactive bladder.

New Diagnostics for Male Lower Urinary Tract Symptoms

PURPOSE OF REVIEW

Lower urinary tract symptoms (LUTS) is a common constellation of symptoms that affect the aging male population with an astonishing prevalence. New technology and new uses of established technology are being used to help further evaluate LUTS in the male population and help guide treatment options. This review focuses on the developments and future directions in diagnostic modalities for evaluation of male LUTS, focusing on evaluation of both the filling and voiding phases of micturition.

RECENT FINDINGS

New techniques in evaluating the voiding phase include penile cuff test, external pressure sensing condom catheter, ultrasound measurement of detrusor wall thickness, ultrasound measurement of intravesical prostatic protrusion, doppler ultrasound and NIRS technology. Evaluation of the filling phase is still undergoing much development and requires additional validation studies. The techniques undergoing evaluation include sensation meters during UDS, assessing bladder micromotion and wall rhythm, assessing detrusor wall biomechanics, ultrasound measurement of detrusor wall thickness, pelvic doppler ultrasound, as well as functional brain imaging including fNIRS and fMRI.

SUMMARY

The development of novel, non-invasive, diagnostic tools have the potential for better evaluation of LUTS with earlier and enhanced treatments. This will likely improve the quality of life for men with LUTS.