Altered domain-specific striatal functional connectivity in patients with Parkinson's disease and urinary symptoms

BACKGROUND

In this study, we aimed at investigating the possible association of urinary symptoms with whole-brain MRI resting-state functional connectivity (FC) alterations from distinct striatal subregions in a large cohort of early PD patients.

METHODS

Seventy-nine drug-naive PD patients (45 PD-urinary+/34 PD-urinary-) and 38 healthy controls (HCs) were consecutively enrolled. Presence/absence of urinary symptoms were assessed by means of the Nonmotor Symptom Scale - domain 7. Using an a priori connectivity-based domain-specific parcellation, we defined three ROIs (per each hemisphere) for different striatal functional subregions (sensorimotor, limbic and cognitive) from which seed-based FC voxel-wise analyses were conducted over the whole brain.

RESULTS

Compared to PD-urinary-, PD-urinary+ patients showed increased FC between striatal regions and motor and premotor/supplementary motor areas as well as insula/anterior dorsolateral PFC. Compared to HC, PD-urinary+ patients presented decreased FC between striatal regions and parietal, insular and cingulate cortices.

CONCLUSIONS

Our findings revealed a specific pattern of striatal FC alteration in PD patients with urinary symptoms, potentially associated to altered stimuli perception and sensorimotor integration even in the early stages. These results may potentially help clinicians to design more effective and tailored rehabilitation and neuromodulation protocols for PD patients.

Optogenetic stimulation of neurons in the anterior cingulate cortex induces changes in intravesical bladder pressure and the micturition reflex

Lower urinary tract (LUT) function is controlled by the central nervous system, including higher-order cognitive brain regions. The anterior cingulate cortex (ACC) is one of these regions, but the role of its activity in LUT function remains poorly understood. In the present study, we conducted optogenetic experiments to manipulate neural activity in mouse ACC while monitoring bladder pressure to elucidate how the activity of ACC regulates LUT function. Selective optogenetic stimulation of excitatory neurons in ACC induced a sharp increase in bladder pressure, whereas activation of inhibitory neurons in ACC prolonged the interval between bladder contractions. Pharmacological manipulation of ACC also altered bladder contractions, consistent with those observed in optogenetic experiments. Optogenetic mapping of the cortical area responsible for eliciting the increase in bladder pressure revealed that stimulation to ACC showed more potent effects than the neighboring motor cortical areas. These results suggest that ACC plays a crucial role in initiating the bladder pressure change and the micturition reflex. Thus, the balance between excitation and inhibition in ACC may regulate the reflex bidirectionally.

The Role of Continuous Theta Burst Stimulation on Primary Motor Cortex in Improving Bladder Function in Post-stroke Patients: A Case Report

Neurogenic bladder (NB) is a frequently encountered post-stroke complication, characterized by symptoms, such as urinary incontinence, dysuria, increased frequency, and urgency. Here, we present a case of a 75-year-old male with urgent urination, frequent urination, urinary incontinence, conspicuous discomfort during urination, and an unpleasant smell in the urine following a stroke. By reviewing the patient's previous medical records of stroke and ruling out other potential causes for bladder dysfunction, a diagnosis of NB could be established. We implemented conventional physical therapy, pelvic floor muscle training with the electromyography biofeedback device, and continuous theta burst stimulation (cTBS) on the contralesional primary motor cortex area to manage bladder function. To the best of our knowledge, this is the first case report on cTBS applied to manage NB after stroke. Our treatment has demonstrated remarkable efficacy in enhancing bladder and kidney function, improving the overall quality of life, and alleviating anxiety and depression symptoms in this patient. This case study concludes that the noninvasive neuromodulation approach exhibits significant potential in the clinical field when addressing this specific patient population.

Effects of central-peripheral FMS on urinary retention after spinal cord injury: a pilot randomized controlled trial protocol

Background

Urinary retention is a common complication of spinal cord injury (SCI), which can seriously affect the quality of life of patients. Function magnetic stimulation (FMS) has been widely used in the recovery of neurological function in various diseases, but its application in urinary retention after SCI remains unclear. Therefore, we would like to conduct a pilot randomized controlled trial (RCT) to observe the feasible effect of FMS on urinary retention after SCI, to explore its mechanism of action.

Method/design

This is a single-center pilot RCT, which 60 patients with urinary retention after SCI will be selected, numbered in chronological order of hospitalization, and randomly divided into 4 groups using the random number table method, Groups A (control group), Group B, Group C, and Group D; Each group will receive the same conventional rehabilitation treatment. The whole intervention period 2 weeks and will be evaluated before and after treatment to collect data on residual bladder volume, functional near-infrared spectroscopy (fNIRS), changes in voiding condition, changes in surface electromyography (SEMG) values of pelvic floor muscle and quality of life scores (QoL).

Study hypothesis

We hypothesized that FMS for the treatment of urinary retention after SCI would have a significant clinical feasible effect;and that peripheral combined with central FMS would be more effective than single-site FMS for the treatment of urinary retention after SCI.

Objective

(1) To illustrate the clinical effectiveness of FMS in the treatment of urinary retention after SCI and to provide a new treatment modality for the patients; (2) Comparison of the differences in the efficacy of central and peripheral single FMS and combined central and peripheral FMS in the treatment of urinary retention after SCI; (3) To explore the central control mechanisms of bladder function recovery after SCI in conjunction with changes in fNIRS.

Trial registration

This study has been ethically approved by the Scientific and Ethics Committee of the First Affiliated Hospital of Gannan Medical university with approval number (LLSC-2022112401). It has been registered with the China Clinical Trials Registry with the registration number: ChiCTR2200067143.

Effects of a new selective β3 -adrenoceptor agonist, vibegron, on bladder and urethral function in a rat model of Parkinson's disease

OBJECTIVES

Parkinson's disease caused by the loss of dopaminergic neurons induces not only motor dysfunction but also lower urinary tract dysfunction. Patients with Parkinson's disease have recently been reported to experience both urge urinary incontinence (overactive bladder) and stress urinary incontinence, the latter of which occurs when the pressure of the bladder exceeds that of the urethra. Vibegron is a highly selective novel β3 -adrenoceptor agonist approved for the treatment of overactive bladder. However, how β3 -adrenoceptor agonists affect urethral function remains unclear. In a clinical report, the urethral function of patients with Parkinson's disease was shown to be degraded. The present study aimed to investigate the effects of vibegron on lower urinary tract activity in a rat model of Parkinson's disease.

METHODS

In a rat model of Parkinson's disease induced by unilateral 6-hydroxydopamine injection into the substantia nigra pars compacta, we examined the effects of vibegron on bladder and urethral activity.

RESULTS

Cystometric analysis revealed that, compared with vehicle injection, intravenous injection of 3 mg/kg vibegron significantly increased the inter-contraction interval (p < .05) and reduced voiding pressure (p < .01). However, no significant effects on urethral function were observed.

CONCLUSIONS

The results of the present study provide corroborating evidence that bladder dysfunction is suppressed by the administration of vibegron in Parkinson's disease model rats, confirming that vibegron is effective for treating overactive bladder without further worsening urethral function. These findings may contribute to a better understanding of the mechanisms of β3 -adrenoceptor agonists.

Differences between brain responses to peroneal electrical transcutaneous neuromodulation and transcutaneous tibial nerve stimulation, two treatments for overactive bladder

OBJECTIVES

To compare brain responses to peroneal electrical transcutaneous neuromodulation (peroneal eTNM®) and transcutaneous tibial nerve stimulation (TTNS), two methods for treating overactive bladder (OAB), using functional magnetic resonance imaging (fMRI). The present study was not designed to compare their clinical efficacy.

MATERIALS AND METHODS

This study included 32 healthy adult female volunteers (average age 38.3 years (range 22-73)). Brain MRI using 3 T scanner was performed during three 8-min blocks of alternating sequences. During each 8-min block, the protocol alternated between sham stimulation (30 s) and rest (30 s) for 8 repeats; then peroneal eTNM® stimulation (30 s) and rest (30 s) for 8 repeats; then, TTNS stimulation (30 s) and rest (30 s) for 8 repeats. Statistical analysis was performed at the individual level with a threshold of p = 0.05, family-wise error (FWE)-corrected. The resulting individual statistical maps were analyzed in group statistics using a one-sample t-test, p = 0.05 threshold, false discovery rate (FDR)-corrected.

RESULTS

During peroneal eTNM®, TTNS, and sham stimulations, we recorded activation in the brainstem, bilateral posterior insula, bilateral precentral gyrus, bilateral postcentral gyrus, left transverse temporal gyrus, and right supramarginal gyrus. During both peroneal eTNM® and TTNS stimulations, but not sham stimulations, we recorded activation in the left cerebellum, right transverse temporal gyrus, right middle frontal gyrus, and right inferior frontal gyrus. Exclusively during peroneal eTNM® stimulation, we observed activation in the right cerebellum, right thalamus, bilateral basal ganglia, bilateral cingulate gyrus, right anterior insula, right central operculum, bilateral supplementary motor cortex, bilateral superior temporal gyrus, and left inferior frontal gyrus.

CONCLUSIONS

Peroneal eTNM®, but not TTNS, induces the activation of brain structures that were previously implicated in neural control of the of bladder filling and play an important role in the ability to cope with urgency. The therapeutic effect of peroneal eTNM® could be exerted, at least in part, at the supraspinal level of neural control.

Real-time changes in brain activity during tibial nerve stimulation for overactive bladder: Evidence from functional near-infrared spectroscopy hype scanning

Purpose

To use functional near-infrared spectroscopy (fNIRS) to identify changes in brain activity during tibial nerve stimulation (TNS) in patients with overactive bladder (OAB) responsive to therapy.

Methods

Eighteen patients with refractory idiopathic OAB patients were recruited consecutively for this pilot study. At baseline, all patients completed 3 days voiding diary, Quality-of-Life score, Perception-of-Bladder-Condition, and Overactive-Bladder-Symptom score. Then 4 region-of-interest (ROI) fNIRS scans with 3 blocks were conducted for each patient. The block design was used: 60 s each for the task and rest periods and 3 to 5 repetitions of each period. A total of 360 s of data were collected. During the task period, patients used transcutaneous tibial nerve stimulation (TTNS) of 20-Hz frequency and a 0.2-millisecond pulse width and 30-milliamp stimulatory current to complete the experiment. The initial scan was obtained with a sham stimulation with an empty bladder, and a second was obtained with a verum stimulation with an empty bladder. Patients were given water till strong desire to void, and the third fNIRS scan with a verum stimulation was performed. The patients then needed to urinate since they could not tolerate the SDV condition for a long time. After a period of rest, the patients then were given water until they exhibited SDV state. The fourth scan with sham fNIRS scan in the SDV state was performed. NIRS_KIT software was used to analyze prefrontal activity, corrected by false discovery rate (FDR, p < 0.05). Statistical analyses were performed using GraphPad Prism software; p < 0.05 was considered significant.

Results

TTNS treatment was successful in 16 OAB patients and unsuccessful in 2. The 3 days voiding diary, Quality-of-Life score, Perception-of-Bladder-Condition, and Overactive-Bladder-Symptom score were significantly improved after TNS in the successfully treated group but not in the unsuccessfully treated group. The dorsolateral prefrontal cortex (DLPFC) (BA 9, Chapters 25 and 26) and the frontopolar area (FA) (BA 10, Chapters 35, 45, and 46) were significantly activated during TNS treatment with an empty bladder rather than with an SDV. Compared with the successfully treated group, the unsuccessfully treated group did not achieve statistical significance with an empty bladder and an SDV state.

Conclusion

fNIRS confirms that TNS influences brain activity in patients with OAB who respond to therapy. That may be the central mechanism of action of TNS.

Pattern of prefrontal cortical activation and network revealed by task-based and resting-state fNIRS in Parkinson’s disease’s patients with overactive bladder symptoms

Background

Overactive bladder (OAB) symptoms are common in Parkinson’s disease (PD), and negatively contribute to the quality of life (QoL) of patients. To explore the underlying pathophysiological mechanism, we investigated the correlation between the prefrontal cortex (PFC) function and OAB symptoms in PD patients.

Methods

One hundred fifty-five idiopathic PD patients were recruited and classified either as PD-OAB or PD-NOAB candidates based on their corresponding OAB symptom scores (OABSS). A linear regression analysis identified a correlative connection of cognitive domains. Then cortical activation during the performance of the verbal fluency test (VFT) and brain connectivity during resting state were conducted by functional near-infrared spectroscopy (fNIRS) for 10 patients in each group to investigate their frontal cortical activation and network pattern.

Results

In cognitive function analysis, a higher OABS score was significantly correlated with a lower FAB score, MoCA total score, and sub-scores of visuospatial/executive, attention, and orientation as well. In the fNIRS study, the PD-OAB group exhibited significant activations in 5 channels over the left hemisphere, 4 over the right hemisphere, and 1 in the median during the VFT process. In contrast, only 1 channel over the right hemisphere showed significant activation in the PD-NOAB group. The PD-OAB group revealed hyperactivation, particularly in certain channel in the left dorsolateral prefrontal cortex (DLPFC), compared with PD-NOAB (FDR P &lt; 0.05). In the resting state, there was a significant increase of the resting state functional connectivity (RSFC) strength between the bilateral Broca area, left frontopolar area (FPA-L) and right Broca’s area (Broca-R), between the FPA and Broca’s area if merging the bilateral regions of interest (ROI), and also between the two hemispheres in the PD-OAB group. The Spearman’s correlation confirmed that the OABS scores were positively correlated with RSFC strength between the bilateral Broca area, FPA-L and Broca-R, between the FPA and Broca area if merging the bilateral ROI.

Conclusion

In this PD cohort, OAB was related to decreased PFC functions, with particularly hyperactivated left DLPFC during VTF and an enhanced neural connectivity between the two hemispheres in the resting state as observed by fNIRS imaging.

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.

Reflex seizures induced by micturition: a case report

Background

Reflex seizures (RS) induced by micturition are extremely rare, and the clinical and electroencephalogram features of RS are not widely known among clinicians. In particular, the origin of the epileptic area is still unclear.

Case presentation

An 8-year-old girl who had generalized tonic-clonic seizures was diagnosed with RS induced by micturition based on the clinical manifestation and EEG recordings. We also reviewed the clinical and EEG characteristics of RS induced by micturition in literature by searching the databases of PubMed and MEDLINE using keywords “micturition reflex seizure”, “reflex seizure induced by micturition”, and “micturition induced seizure” by January 2022. We speculate that the mechanism of micturition-induced RS may involve excessive neuronal excitation in regions that participate in micturition.

Conclusions

The RS in this patient was considered to be induced by micturition. Awareness should be raised to this rare form of RS among practitioners.

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.

Altered resting-state functional connectivity of insula in children with primary nocturnal enuresis

Objective

Primary nocturnal enuresis (PNE) is a common developmental condition in school-aged children. The objective is to better understand the pathophysiology of PNE by using insula-centered resting-state functional connectivity (rsFC).

Methods

We recruited 66 right-handed participants in our analysis, 33 with PNE and 33 healthy control (HC) children without enuresis matched for gender and age. Functional and structural MRI data were obtained from all the children. Seed-based rsFC was used to examine differences in insular functional connectivity between the PNE and HC groups. Correlation analyses were carried out to explore the relationship between abnormal insula-centered functional connectivity and clinical characteristics in the PNE group.

Results

Compared with HC children, the children with PNE demonstrated decreased left and right insular rsFC with the right medial superior frontal gyrus (SFG). In addition, the bilateral dorsal anterior insula (dAI) seeds also indicated the reduced rsFC with right medial SFG. Furthermore, the right posterior insula (PI) seed showed the weaker rsFC with the right medial SFG, while the left PI seed displayed the weaker rsFC with the right SFG. No statistically significant correlations were detected between aberrant insular rsFC and clinical variables (e.g., micturition desire awakening, bed-wetting frequency, and bladder volume) in results without global signal regression (GSR) in the PNE group. However, before and after setting age as a covariate, significant and positive correlations between bladder volume and the rsFC of the left dAI with right medial SFG and the rsFC of the right PI with right medial SFG were found in results with GSR in the PNE group.

Conclusion

To the best of our knowledge, this study explored the rsFC patterns of the insula in children with PNE for the first time. These results uncovered the abnormal rsFC of the insula with the medial prefrontal cortex without and with GSR in the PNE group, suggesting that dysconnectivity of the salience network (SN)-default mode network (DMN) may involve in the underlying pathophysiology of children with PNE. However, the inconsistent associations between bladder volume and dysconnectivity of the SN-DMN in results without and with GSR need further studies.

Ventrolateral Periaqueductal Gray Neurons Are Active During Urination

The ventrolateral periaqueductal gray (VLPAG) is thought to be the main PAG column for bladder control. PAG neurons (especially VLPAG neurons) and neurons in the pontine micturition center (PMC) innervating the bladder detrusor have anatomical and functional synaptic connections. The prevailing viewpoint on neural control of the bladder is that PAG neurons receive information on the decision to void made by upstream brain regions, and consequently activate the PMC through their direct projections to initiate urination reflex. However, the exact location of the PMC-projecting VLPAG neurons, their activity in response to urination, and their whole-brain inputs remain unclear. Here, we identified the distribution of VLPAG neurons that may participate in control of the bladder or project to the PMC through retrograde neural tracing. Population Ca2+ signals of PMC-projecting VLPAG neurons highly correlated with bladder contractions and urination as shown by in vivo recording in freely moving animals. Using a RV-based retrograde trans-synaptic tracing strategy, morphological results showed that urination-related PMC-projecting VLPAG neurons received dense inputs from multiple urination-related higher brain areas, such as the medial preoptic area, medial prefrontal cortex, and lateral hypothalamus. Thus, our findings reveal a novel insight into the VLPAG for control of bladder function and provide a potential therapeutic midbrain node for neurogenic bladder dysfunction.

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.

Neural circuit control of innate behaviors

All animals possess a plethora of innate behaviors that do not require extensive learning and are fundamental for their survival and propagation. With the advent of newly-developed techniques such as viral tracing and optogenetic and chemogenetic tools, recent studies are gradually unraveling neural circuits underlying different innate behaviors. Here, we summarize current development in our understanding of the neural circuits controlling predation, feeding, male-typical mating, and urination, highlighting the role of genetically defined neurons and their connections in sensory triggering, sensory to motor/motivation transformation, motor/motivation encoding during these different behaviors. Along the way, we discuss possible mechanisms underlying binge-eating disorder and the pro-social effects of the neuropeptide oxytocin, elucidating the clinical relevance of studying neural circuits underlying essential innate functions. Finally, we discuss some exciting brain structures recurrently appearing in the regulation of different behaviors, which suggests both divergence and convergence in the neural encoding of specific innate behaviors. Going forward, we emphasize the importance of multi-angle and cross-species dissections in delineating neural circuits that control innate behaviors.

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.

Relationship between sleep respiration, architecture and childhood enuresis: Correlates between polysomnography and questionnaire

AIM

Nocturnal enuresis (NE) and sleep-disordered breathing (SDB) are common in childhood. While the two disorders are linked, those links are still being clarified.

METHODS

This study compared sleep profiles and enuresis-related behaviours between children with NE and those without, who were referred to a tertiary sleep unit with suspected SDB, using the combination of polysomnography (PSG) and questionnaire. Continuous numerical data were analysed after adjusting for body mass index z-score.

RESULTS

The study included 52 Children (39 boys, 13 girls) aged 5-14 years. Twenty-one had enuresis (10 monosymptomatic enuresis (MNE) and 11 non-monosymptomatic enuresis (NMNE)) and 31 did not have enuresis. The majority had comorbidities. On PSG, all children with NE had moderate obstructive sleep apnoea (OSA) compared to the control group which were of mild OSA. Children with NMNE had a higher percentage time in stage-3 non-REM sleep when compared to the non-enuretic and MNE groups (P < 0.05). On the questionnaire, more parents of the NE groups reported that their child was 'difficult to wake in the morning' (P < 0.05).

CONCLUSION

In this heterogeneous population referred for suspected SDB, children with NE had moderate OSA, yet those with MNE had increased arousals and more often report difficulty waking than children with suspected SDB who do not wet, while children with NMNE exhibit changes in sleep architecture suggesting deeper sleep. These differences may impact treatment choices for children with enuresis.

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.

Regional activity and functional connectivity in brain networks associated with urinary bladder filling in patients with tethered cord syndrome

PURPOSE

Abnormal neural activities can be revealed by resting-state functional magnetic resonance imaging using analyses of regional activity and functional connectivity of brain networks. This study was designed to demonstrate functional network alterations in patients with detrusor overactivity.

MATERIALS AND METHODS

In this study, we recruited 36 patients with tethered cord syndrome who had detrusor overactivity and 34 normal controls. We used regional homogeneity and seed-based functional connectivity computational methods to reveal resting-state brain activity features associated with patients.

RESULTS

Compared with normal controls, patients with tethered cord syndrome showed regional abnormalities, mainly in the bilateral frontal cortex, anterior and midcingulate cortex, and temporal lobes. When these regions were defined as seeds, we demonstrated widespread modification in brain networks. The brain-bladder network was not positively connected with the cognitive control network. Both altered regional activity and changed functional connectivity were found in the brain-bladder network.

CONCLUSION

Patients with NDO, activated areas in the frontal lobe and anterior cingulate gyrus decreased significantly and have fewer brain activation areas in the caudate nucleus and hypothalamus (limbic system). In functional connectivity work, we found a small positive correlation in different regions of frontal lobe. This study helped us better to understand the characteristics of neural network modifications in patients with tethered cord syndrome.

Abnormal functional connectivity within the prefrontal cortex in interstitial cystitis/bladder pain syndrome (IC/BPS): A pilot study using resting state functional near-infrared spectroscopy (rs-fNIRS)

PURPOSE

To investigate the abnormalities of functional connectivity (FC) within the prefrontal cortex (PFC) of patients with interstitial cystitis/bladder pain syndrome (IC/BPS) based on resting state functional near-infrared spectroscopy (rs-fNIRS) data using FC matrix analysis.

MATERIALS AND METHODS

Ten patients with IC/BPS (females, 9; mean age, 56.9 ± 12.432 years) and 15 age- and gender-matched healthy controls (HC) (females, 12; mean age, 55.067 ± 7.46 years) participated in this rs-fNIRS study. Two rs-fNIRS scans were performed (when the bladder was empty and when the desire to void was strong). The Pearson's correlation coefficient between the time series of the 22 channels was calculated to obtain a 22 × 22 FC matrix for each subject. A two-sample t-test (p < .05) was performed to compare group differences in the FC matrix between patients with IC/BPS and HC.

RESULTS

FC was significantly decreased within the PFC in the IC/BPS group based on a two-sample t-test (p < .05) compared with HC. FC decreased in a wider range of brain regions during the strong desire to void state (4 brain regions and 28 edges) when compared with the empty bladder state (3 brain regions and 18 edges).

CONCLUSION

FC abnormalities in IC/BPS patients may lead to frontal lobe disorders involved in processing sensory integration, motivation drive, emotional control, and decision-making whether to urinate, leading to urinary control dysfunction manifested as typical clinical IC/BPS symptoms. Our results may provide new insight into the pathogenesis of IC/BPS and new brain biomarkers for diagnosis.

A systematic review and activation likelihood estimation meta-analysis of the central innervation of the lower urinary tract: Pelvic floor motor control and micturition

Purpose

Functional neuroimaging is a powerful and versatile tool to investigate central lower urinary tract (LUT) control. Despite the increasing body of literature there is a lack of comprehensive overviews on LUT control. Thus, we aimed to execute a coordinate based meta-analysis of all PET and fMRI evidence on descending central LUT control, i.e. pelvic floor muscle contraction (PFMC) and micturition.

Materials and methods

A systematic literature search of all relevant libraries was performed in August 2020. Coordinates of activity were extracted from eligible studies to perform an activation likelihood estimation (ALE) using a threshold of uncorrected p <0.001.

Results

20 of 6858 identified studies, published between 1997 and 2020, were included. Twelve studies investigated PFMC (1xPET, 11xfMRI) and eight micturition (3xPET, 5xfMRI). The PFMC ALE analysis (n = 181, 133 foci) showed clusters in the primary motor cortex, supplementary motor cortex, cingulate gyrus, frontal gyrus, thalamus, supramarginal gyrus, and cerebellum. The micturition ALE analysis (n = 107, 98 foci) showed active clusters in the dorsal pons, including the pontine micturition center, the periaqueductal gray, cingulate gyrus, frontal gyrus, insula and ventral pons. Overlap of PFMC and micturition was found in the cingulate gyrus and thalamus.

Conclusions

For the first time the involved core brain areas of LUT motor control were determined using ALE. Furthermore, the involved brain areas for PFMC and micturition are partially distinct. Further neuroimaging studies are required to extend this ALE analysis and determine the differences between a healthy and a dysfunctional LUT. This requires standardization of protocols and task-execution.

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.

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.

Association between urinary symptom severity and white matter plaque distribution in women with multiple sclerosis

AIMS

Multiple sclerosis (MS) is characterized by demyelinated white matter plaque throughout the central nervous system. Plaque involvement in regions that regulate micturition may be associated with urinary symptom severity in patients with MS. The aim of this prospective study is to investigate the relationship between cerebral plaque volume (PV), location, and urinary symptoms in women with MS.

METHODS

We conducted a case-control pilot study of women with MS undergoing routine yearly brain MRI. Women were administered the American Urologic Association-Symptom Index (AUA-SI) and divided into two groups: severe urinary symptoms (AUA-SI ≥20) and mild symptoms (AUA-SI ≤7). PV and location in the brain were determined using a validated automated white matter lesion segmentation algorithm.

RESULTS

This study of 36 women found that the median total PV did not differ between groups. Women with severe urinary symptoms had larger median PV in the left frontal lobe (LFL) and right limbic lobe (RLL) compared with women with mild urinary symptoms. Within the RLL, women with severe symptoms had a larger median PV in the right cingulate gyrus (RCG). There was a moderate correlation between LFL lesion volume and RLL lesion volume with the AUA emptying subscore; however, these regions did not correlate with the storage subscore.

CONCLUSIONS

This preliminary study found urinary symptom severity in women with MS is associated with PV in the RCG and LFL, and not total cerebral PV. These findings may explain why disease burden alone is not a predictor of severity or type of voiding dysfunction in patients with MS.

Study on neuropathological mechanisms of primary monosymptomatic nocturnal enuresis in children using cerebral resting-state functional magnetic resonance imaging

Primary monosymptomatic nocturnal enuresis (PMNE) is a heterogeneous disorder, which remains a difficult condition to manage due to lack of knowledge on the underlying pathophysiological mechanisms. Here we investigated the underlying neuropathological mechanisms of PMNE with functional MRI (fMRI), combining the amplitude of low frequency fluctuation (ALFF), regional homogeneity (ReHo), and seed-based functional connectivity (seed-based FC) analyses. Compared to the control group, PMNE group showed decreased ALFF value in the left medial orbital superior frontal gyrus (Frontal_Med_Orb_L), and increased ReHo value in the left superior occipital gyrus (Occipital_Sup_L). With left thalamus as the seed, PMNE group showed significantly decreased functional connectivity to the left medial superior frontal gyrus (Frontal_Sup_Medial_L). We conclude that these abnormal brain activities are probably important neuropathological mechanisms of PMNE in children. Furthermore, this study facilitated the understanding of underlying pathogenesis of PMNE and may provide an objective basis for the effective treatment.

Neural Correlates of Urinary Retention in Lateral Medullary Infarction

Purpose

The brainstem plays an important role in the control of micturition, and brainstem strokes are known to present with micturition dysfunction. Micturition dysfunction in cases of lateral medullary infarction (LMI) is uncommon, but often manifests as urinary retention. In this study, we investigated the neuro-anatomical correlates of urinary retention in patients with LMI.

Methods

This was a hospital-based retrospective study conducted in the neurology unit of a quaternary-level teaching hospital. Inpatient records from January 2008 to May 2018 were searched using a computerized database. Cases of isolated LMI were identified and those with micturition dysfunction were reviewed. MRI brain images of all patients were viewed, and individual lesions were mapped onto the Montreal Neurological Institute (MNI) space manually using MRIcron. Nonparametric mapping toolbox software was used for voxel-based lesion-symptom analysis. The Liebermeister test was used for statistical analysis, and the resultant statistical map was displayed on the MNI template using MRIcron.

Results

During the study period, 31 patients with isolated LMI were identified. Their mean age was 48 years and 28 (90%) were male. Six of these patients (19%) developed micturition dysfunction. All 6 patients had urinary retention and 1 patient each had urge incontinence and overflow incontinence. In patients with LMI, the lateral tegmentum of the medulla showed a significant association with urinary retention.

Conclusions

In patients with isolated LMI, we postulate that disruption of the descending pathway from the pontine micturition centre to the sacral spinal cord at the level of the lateral tegmentum results in urinary retention.

Clinical study of the effects of deep brain stimulation on urinary dysfunctions in patients with Parkinson's disease

Purpose: To evaluate the effect of deep brain stimulation (DBS) on urinary dysfunctions in Parkinson’s patients.

Patients and methods: A total of 416 patients, diagnosed with Parkinson’s disease (PD) based on the UK Parkinson’s Disease Society Brain Bank Diagnostic Criteria, were enrolled in the study, including 307 males and 109 females. The effects of DBS treatment on urinary functions during urination and bladder storage of these patients were evaluated using testing and assessment scales, such as the American Urological Association Symptom Index (AUA-SI), Overactive Bladder Symptom Scores (OAB-SS), Quality Of Life Scale (QOL), and urodynamic tests. The data were statistically analyzed with the chi-square test and  both independent-samples t-test and paired-samples t-test were used in this study.

Results: Symptoms of urinary dysfunctions, such as urinary frequency, urgency, and incontinence, in the patients with PD were notably relieved by DBS treatment (P<0.05), and the OAB-SS and bladder storage problems were greatly improved as well (P<0.05). Compared with those in male patients, DBS surgery significantly improved the AUA-SI, urinary symptom scores, and QOL in female PD patients (P<0.05), as well as other functional indicators related to the urinary tract, including the maximum urinary flow rate, detrusor pressure at peak flow, and residual urine volume in female PD patients (P<0.05).

Conclusion: DBS surgery is effective in improving urinary functions in PD patients, as primarily reflected by the alleviation of urinary symptoms such as urinary frequency, urgency, and incontinence. Female PD patients displayed better urinary function outcomes from DBS treatment than did male patients.

Midcingulate somatomotor and autonomic functions

The midcingulate cortex (MCC) is viewed as a central node within a large-scale system devoted to adjusting behavior in the face of changing environments. Whereas the role of the MCC in interfacing action and cognition is well established, its role in regulating the autonomic nervous system is poorly understood. Yet, adaptive reactions to novel or threatening situations induce coordinated changes in the sympathetic and the parasympathetic systems. The somatomotor maps in the MCC are organized dorsoventrally. A meta-analysis of the literature reveals that the dorsoventral organization might also concern connections with the autonomic nervous system. Activation of the dorsal and ventral parts of the MCC correlate with recruitments of the sympathetic and the parasympathetic systems, respectively. Data also suggest that, in the MCC, projections toward the sympathetic system are mapped along the sensory-motor system following the same cervico-sacral organization as projections on the spinal cord for skeletal motor control.

Assessment of brain activity during voluntary anal sphincter contraction: Comparative study in women with and without fecal incontinence

BACKGROUND

Voluntary anal sphincter function is driven by an extended network of brain structures, most of which are still unknown. Disturbances in this function may cause fecal incontinence. The aim of this study was to characterize the cerebral areas involved in voluntary contraction of the anorectal sphincter in healthy women and in a group of patients with fecal incontinence by using a standardized functional magnetic resonance imaging (fMRI) protocol.

METHODS

This comparative study included 12 healthy women (mean age 53.17 ± 4.93 years) and 12 women with fecal incontinence (56.25 ± 6.94 years). An MRI-compatible anal manometer was used to register voluntary external anal sphincter contraction. During brain fMRI imaging, participants were cued to perform 10-s series of self-paced anal sphincter contractions at an approximate rate of 1 Hz. Brain structures linked to anal sphincter contractions were mapped and the findings were compared between the 2 study groups.

KEY RESULTS

There were no differences in the evoked brain activity between the 2 groups. In healthy women, group fMRI analysis revealed significant activations in medial primary motor cortices, supplementary motor area, bilateral putamen, and cerebellum, as well as in the supramarginal gyrus and visual areas. In patients with fecal incontinence, the activation pattern involved similar regions without significant differences with healthy women.

CONCLUSIONS & INFERENCES

This brain fMRI-anorectal protocol was able to map the brain regions linked to voluntary anal sphincter function in healthy and women with fecal incontinence.

Angiotensin II, a stress-related neuropeptide in the CNS, facilitates micturition reflex in rats

BACKGROUND AND PURPOSE

We investigated the effects of centrally administered stress-related neuropeptide, angiotensin II, on the micturition reflex and the downstream signalling pathways in rats.

EXPERIMENTAL APPROACH

Male Wistar rats were anaesthetized with urethane for cystometry before and after i.c.v. administration of vehicle or angiotensin II (30 pmol). Muscimol (a GABA_A receptor agonist) or baclofen (a GABA_B receptor agonist) was i.c.v. administered 30 min before or 15 min after central angiotensin II administration. Telmisartan [an angiotensin II type 1 (AT₁ ) receptor antagonist], valsartan (an AT₁ receptor antagonist), PD123319 (an AT₂ receptor antagonist), U-73122 (a PLC inhibitor), chelerythrine chloride (a PKC inhibitor), apocynin (a NADPH oxidase inhibitor) or tempol (an antioxidant) was centrally administered 30 min before central angiotensin II administration.

KEY RESULTS

Centrally administered angiotensin II significantly shortened the intercontraction interval and decreased the voided volume and bladder capacity without altering the maximum voiding pressure, post-voiding residual urine volume or voiding efficacy. Muscimol, baclofen, telmisartan, valsartan, U-73122, chelerythrine chloride, apocynin or tempol pretreatment significantly suppressed the reduction in intercontraction interval induced by central angiotensin II. Post-treatment with muscimol or baclofen also ameliorated the decrease in intercontraction interval induced by central angiotensin II.

CONCLUSIONS AND IMPLICATIONS

Angiotensin II in the CNS facilitates micturition reflex by inhibiting central GABAergic activity and activating the AT₁ receptor/PLC/PKC/NADPH oxidase/superoxide anion pathway.

The efficacy of mirabegron in the treatment of urgency and the potential utility of combination therapy

Urgency is the prevalent and most bothersome symptom of overactive bladder (OAB) and the treatment of urgency is the primary objective in the management of OAB. Urgency has a major impact on other symptoms of OAB and culminates in an increased frequency of micturition and reduced volume voided, which may contribute to shorter intervals between the need to void. Antimuscarinic agents and mirabegron, a β3-adrenoceptor agonist, constitute the main oral pharmacotherapeutic options for the treatment of urgency and other OAB symptoms. The reduction of urgency and other OAB symptoms significantly improve health-related quality of life. This review will explore the distinct mechanisms of action and effects of antimuscarinic agents and mirabegron, in relation to their effect on the pathophysiology of urgency. The review will also provide an overview of the various validated measurements of urgency and the numerous clinical trials regarding antimuscarinic agent monotherapy, mirabegron monotherapy, or combination treatment with mirabegron added on to the antimuscarinic agent solifenacin. A narrative review of the literature relating to pathophysiology of urgency, the validated measurements of urgency, and clinical trials relating to the pharmacological treatment of urgency. Antimuscarinic agent monotherapy, mirabegron monotherapy, or combination treatment with mirabegron added on to the antimuscarinic agent solifenacin statistically significantly reduce the symptoms of urgency compared with placebo. Combination therapy with mirabegron added on to solifenacin also statistically significantly reduces the symptoms of severe urgency compared with antimuscarinic agent monotherapy. A critique of the clinical benefits of combination therapy is also provided. Combination therapy provides an alternative treatment in patients with OAB that includes urgency who respond poorly to first-line monotherapy and who may otherwise often move on to more invasive treatments.

Add-on Therapy With the α-Blockers Tamsulosin and Naftopidil Improves Voiding Function by Enhancing Neuronal Activity in Prostatic Hyperplasia Rats

Purpose

Benign prostatic hyperplasia (BPH) impacts quality of life in men by causing lower urinary tract symptoms. α1-Adrenoceptor (α1-AR) blockers improve lower urinary tract symptoms. We investigated the efficacy of add-on therapy with α1-AR blockers on BPH rats.

Methods

Rats in the drug-treated groups were orally administered each drug once a day for 30 days after orchiectomy. To induce BPH, rats were castrated and testosterone (20 mg/kg) was injected subcutaneously once per day for 30 days. Cystometry was conducted to measure voiding contraction pressure and the interval contraction time, immunohistochemistry was performed to measure c-Fos and nerve growth factor (NGF) expression in the neuronal voiding centers, and nicotinamide adenine dinucleotide phosphate-diaphorase histochemistry was used to measure nitric oxide synthase (NOS) expression.

Results

Orchiectomy and testosterone injection decreased voiding contraction pressure and the interval contraction time, suggesting BPH symptoms. Voiding contraction pressure and the interval contraction time were greater in the group that received the combination treatment (tamsulosin with naftopidil) than in the tamsulosin monotherapy or naftopidil monotherapy groups. c-Fos, NGF, and NOS expression in the neuronal voiding centers was enhanced by BPH induction. c-Fos, NGF, and NOS expression was suppressed by the combination treatment (tamsulosin with naftopidil) to a greater extent than was the case for tamsulosin monotherapy or naftopidil monotherapy.

Conclusions

Combination therapy of tamsulosin and naftopidil showed greater efficacy for the treatment of BPH than tamsulosin monotherapy or naftopidil monotherapy; therefore, combination therapy can be considered as a novel therapeutic method for BPH.

Central Regulation of Micturition and Its Association With Epilepsy

Micturition is a complex process involving the bladder, spinal cord, and the brain. Highly sophisticated central neural program controls bladder function by utilizing multiple brain regions, including pons and suprapontine structures. Periaqueductal grey, insula, anterior cingulate cortex, and medial prefrontal cortex are components of suprapontine micturition centers. Under pathologic conditions such as epilepsy, urinary dysfunction is a frequent symptom and it seems to be associated with increased suprapontine cortical activity. Interestingly, micturition can also trigger seizures known as reflex epilepsy. During voiding behavior, frontotemporal cortical activation has been reported and it may induce reflex seizures. As current researches are only limited to present clinical cases, more rigorous investigations are needed to elucidate biological mechanisms of micturition to advance our knowledge on the process of micturition in physiology and pathology.

Is there "brain OAB" and how can we recognize it? International Consultation on Incontinence-Research Society (ICI-RS) 2017

AIMS

In light of mounting evidence supporting the association of brain regions with the control of urine storage and voiding, the high placebo effect in OAB studies as well as certain anecdotal observations from clinical practice with OAB patients, the role of the brain in OAB was explored.

METHODS

At the ICI-RS 2017 meeting, a panel of Functional Urologists and Basic Scientists presented literature data generating a proposal to discuss whether there is "brain OAB" and how we could recognize it.

RESULTS

Existing data point toward organic brain causes of OAB, in particular concerning white matter disease (WMD) and aging, but with currently speculative mechanisms. Imaging techniques have revealed connectivity changes between brain regions which may explain brain-peripheral interactions in OAB patients, further to acknowledged structural and functional changes in the central nervous system (CNS). Furthermore, psychological disorders like stress and depression have been identified as causes of OAB, with animal and human studies proposing a neurochemical and neuroendocrine pathophysiological basis, involving either the serotoninergic system or the hypothalamic-pituitary-adrenal axis. Finally, childhood data suggest that OAB could be a developmental disorder involving the CNS, although childhood OAB could be a different condition than that of adults in many children.

CONCLUSIONS

Future research should aim to identify the pathogenesis of WMD and the aging processes affecting the brain and the bladder, with possible benefits in prevention strategies, as well as connectivity disorders within the CNS, the pathophysiology of OAB in childhood and the neurochemical pathways connecting affective disorders with OAB.

Morphometric Magnetic Resonance Imaging Study in Children With Primary Monosymptomatic Nocturnal Enuresis

OBJECTIVE

Primary monosymptomatic nocturnal enuresis (PMNE) refers to bed-wetting in children who have no other lower urinary tract symptoms and are never dry for more than 6 months. Our previous studies demonstrated that children with PMNE exhibited brain functional abnormalities compared with healthy controls; however, researches on the abnormalities in gray matter were limited. This study aimed to investigate brain structural changes in gray matter of children with PMNE using magnetic resonance imaging (MRI).

METHODS

Gray matter volumes (GMVs) and gyrification indices (GIs) were calculated using voxel-based and surface-based morphometry analyses of structural MRI data acquired from 26 children with PMNE and 28 healthy children. To identify between-group differences in gray matter, two-sample t-tests were conducted on GMV and GI images separately.

RESULTS

Compared with the controls, children with PMNE showed significantly increased GMVs in the supplementary motor area and medial prefrontal cortex regions (mean GMV in PMNE: 0.54 ± 0.07 l; mean GMV in controls: 0.50 ± 0.06 l) and reduced GIs in the right precuneus (mean GI in PMNE: 25.74° ± 2.34°; mean GI in controls: 27.97° ± 1.79°).

CONCLUSION

Children with PMNE showed abnormal GMVs in frontal lobe and GIs in precuneus, and these changes might be involved in the pathological mechanism of PMNE.

Effects of Combination Treatment of Alpha 1-Adrenergic Receptor Antagonists on Voiding Dysfunction: Study on Target Organs in Overactive Bladder Rats

PURPOSE

Overactive bladder (OAB) causes urinary urgency, usually accompanied by frequency and nocturia. Alpha 1-adrenergic receptor (α₁-AR) antagonists are known to improve lower urinary tract symptoms associated with OAB. The α₁-AR antagonists constitute a variety of drugs according to the receptor subtype affinity. This study investigated the efficacy of tamsulosin, naftopidil, and a combination of the two on OAB rats.

METHODS

The OAB rat model was induced by an intraperitoneal injection of cyclophosphamide for 14 days. The experimental groups were divided into 5 groups: control group, OAB-induction group, OAB-induction and tamsulosin monotherapy group, OAB-induction and naftopidil monotherapy group, and OAB-induction and tamsulosin-naftopidil combination therapy group. For the drug-treated groups, each drug was administrated for 14 days after the OAB induction. Cystometry for urodynamic evaluation and immunohistochemical stain for c-Fos and nerve growth factor (NGF) expressions in the central micturition centers were performed.

RESULTS

Increased contraction pressure and time with enhanced c-Fos and NGF expressions in the central micturition centers were found in the OAB rats. Tamsulosin suppressed contraction pressure and time while inhibiting c-Fos and NGF expressions. Naftopidil showed no significant effect and combination therapy showed less of an effect on contraction pressure and time. Naftopidil and combination therapy exerted no significant effect on the c-Fos and NGF expressions.

CONCLUSIONS

Tamsulosin showed the most prominent efficacy for the treatment of OAB compared to the naftopidil and combination. The combination of tamsulosin with naftopidil showed no synergistic effects on OAB; however, further studies of addon therapy might provide opportunities to find a new modality.

Lower urinary tract symptoms in Parkinson's disease: Prevalence, aetiology and management

Lower urinary tract symptoms (LUTS) are common in Parkinson's disease (PD), effecting 27-85% of patients with PD. Irritative symptoms predominate and urodynamic studies confirm high prevalence of detrusor overactivity in PD. LUTS are present early in PD and are more common in PD than in age matched controls. The assessment of LUTS in PD is complicated by coexisting bradykinesia and cognitive impairment. Although LUTS become more troublesome as PD progresses it remains unclear if LUTS severity correlates with motor symptoms and/or duration of PD. The underlying cause of LUTS in PD remains to be fully elucidated. Animal and human studies suggest the net effect of the basal ganglia is to supress micturition. Although LUTS are a common in PD, few studies have examined the assessment and management of LUTS specifically in patients with PD. Pilot studies have suggested that bladder training, antimuscarinic drugs and intravesical botulinum toxin maybe helpful but these trials have been small and frequently lacked a suitable control group making them vulnerable to the placebo effect. Furthermore the adverse effects of antimuscarinic drugs on cognitive and gastrointestinal function may limit the use of these drugs in PD. In this review we summarise the literature describing the prevalence of LUTS in PD, discuss the emerging data delineating the underlying pathophysiology of LUTS and examine interventions helpful in the management of LUTS in people with PD.

Functional Magnetic Resonance Imaging with Concurrent Urodynamic Testing Identifies Brain Structures Involved in Micturition Cycle in Patients with Multiple Sclerosis

PURPOSE

Neurogenic lower urinary tract dysfunction, which is common in patients with multiple sclerosis, has a significant impact on quality of life. In this study we sought to determine brain activity processes during the micturition cycle in female patients with multiple sclerosis and neurogenic lower urinary tract dysfunction.

MATERIALS AND METHODS

We report brain activity on functional magnetic resonance imaging and simultaneous urodynamic testing in 23 ambulatory female patients with multiple sclerosis. Individual functional magnetic resonance imaging activation maps at strong desire to void and at initiation of voiding were calculated and averaged at Montreal Neuroimaging Institute. Areas of significant activation were identified in these average maps. Subgroup analysis was performed in patients with elicitable neurogenic detrusor overactivity or detrusor-sphincter dyssynergia.

RESULTS

Group analysis of all patients at strong desire to void yielded areas of activation in regions associated with executive function (frontal gyrus), emotional regulation (cingulate gyrus) and motor control (putamen, cerebellum and precuneus). Comparison of the average change in activation between previously reported healthy controls and patients with multiple sclerosis showed predominantly stronger, more focal activation in the former and lower, more diffused activation in the latter. Patients with multiple sclerosis who had demonstrable neurogenic detrusor overactivity and detrusor-sphincter dyssynergia showed a trend toward distinct brain activation at full urge and at initiation of voiding respectively.

CONCLUSIONS

We successfully studied brain activation during the entire micturition cycle in female patients with neurogenic lower urinary tract dysfunction and multiple sclerosis using a concurrent functional magnetic resonance imaging/urodynamic testing platform. Understanding the central neural processes involved in specific parts of micturition in patients with neurogenic lower urinary tract dysfunction may identify areas of interest for future intervention.

(18F)FDG-PET brain imaging during the micturition cycle in rats detects regions involved in bladder afferent signalling

BACKGROUND

This feasibility study established an experimental protocol to evaluate brain activation patterns using fluorodeoxyglucose positron emission tomography ((18F)FDG-PET) during volume-induced voiding and isovolumetric bladder contractions in rats.

METHODS

Female Sprague-Dawley rats were anaesthetized with urethane and underwent either volume-induced voiding cystometry or isovolumetric cystometry and simultaneous functional PET brain imaging after injection of (18F)FDG in the tail vein. Brain glucose metabolism in both groups was compared to their respective control conditions (empty bladder). Relative glucose metabolism images were anatomically standardized to Paxinos space and analysed voxel-wise using Statistical Parametric Mapping 12 (SPM12).

RESULTS

During volume-induced voiding, glucose hypermetabolism was observed in the insular cortex while uptake was decreased in a cerebellar cluster and the dorsal midbrain. Relative glucose metabolism during isovolumetric bladder contractions increased in the insular and cingulate cortices and decreased in the cerebellum.

CONCLUSIONS

Our findings demonstrate that volume-induced voiding as well as isovolumetric bladder contractions in rats provokes changes in brain metabolism, including activation of the insular and cingulate cortices, which is consistent with their role in the mapping of bladder afferent activity. These findings are in line with human studies. Our results provide a basis for further research into the brain control of the lower urinary tract in small laboratory animals.