Lower urinary tract function in patients with pituitary adenoma compressing hypothalamus

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.

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.

A Longitudinal, Prospective Study to Evaluate the Effects of Treatment on the Inhibitory Control Function After Transsphenoidal Surgery for Pituitary Adenomas

OBJECTIVES

Injured cognitive abilities have been reported in patients with pituitary adenoma. However, to date, few researchers have directly investigated the electrophysiological study of inhibitory control function of pituitary patients both pre- and postsurgery. Thus, this study aimed to identify the factors affecting the inhibitory control function of pituitary patients.

METHODS

Thirty presurgery pituitary patients were recruited and 26 patients of them completed the postsurgery follow-up. Thirty healthy people were recruited for control group. Visual Go/Nogo tasks were carried out by the patients and controls to assess the inhibitory control function before surgery and 6 months after the surgery, respectively. The function of inhibitory control was analyzed with the components of N2 and P3.

RESULTS

Across 3 groups, Nogo stimuli evoked larger frontal-central N2nogo and P3nogo than Go stimuli did. Furthermore, N2d of presurgery patients (-1.14 μV) and postsurgery patients(-0.61 μV) were significantly decreased compared with that of control group (-3.09 μV), F(2, 83) = 13.92, P < .01, whereas no difference was detected between pre- and postsurgery groups. There was no remarkable difference in the amplitude of P3d among the 3 groups, F(2, 83) = 0.19, P > .05. With regard to the amplitude of P3 for Go condition, The P3 amplitude of healthy group (4.38 μV) was larger than both pre- and postsurgery (1.00 μV and 3.01 μV). With regard to the amplitude of P3 for Nogo condition, The P3 amplitude of healthy group (5.25 μV) was larger than both pre- and postsurgery groups (2.35 μV and 4.18 μV).

CONCLUSIONS

These results indicated that presurgery patients showed the dysfunction of inhibition, due to the nerve tissue damage or brain structure alteration caused by the presurgery physical pressure from tumor and abnormal hormone levels. Postsurgery patients showed a tendency toward recovery, but there was no obvious improvement in the inhibitory control function after successful treatments.

Improvement in Attention Processing After Surgical Treatment in Functional Pituitary Adenomas: Evidence From ERP Study

Cognitive abilities are impaired in patients with pituitary adenoma. However, studies on attention processing impairment in preoperative patients and attention processing recovery after transsphenoidal adenomectomy are lacking. The study aims to identify the electrophysiological change that relates to attention processing in pituitary patients before and after treatment. Twenty five preoperative pituitary patients and 25 follow-up postoperative patients were recruited. 27 healthy controls (HCs) were matched to the patients with age, gender, and education. Event-related potentials were used to investigate the attention processing in the preoperative patients, postoperative patients, and HCs. Across three groups, all emotional stimuli evoked P200 components. Compared with the HCs or postoperative patients, the amplitudes of P200 in the preoperative patients were higher. Moreover, The amplitudes of P200 decreased in the postoperative patients, which were similar to that in the HCs. The attention processing was improved after surgery, but no significant differences were detected between the postoperative patients and HCs. Abnormal hormone levels may be relevant to the factor that impair attention processing. Compared with that of the HCs and postoperative patients, the P200 component elicited by negative stimuli is higher in preoperative patients, which may illustrate compensatory activity after attention impairments. Furthermore, these data indicate that improvements in attention processing may be attributed to the amelioration of endocrine disorders. This study shows that the P200 component may be used to diagnose attention processing in preoperative pituitary patients and prove the improvement of attention processing in postoperative patients.

Altered Connectivity of the Frontoparietal Network During Attention Processing in Prolactinomas

Prolactinomas have been reported for the failure of cognitive functions. However, the electrophysiological mechanisms of attention processing in prolactinomas remain unclear. In a visual mission, we monitored the scalp electroencephalography (EEG) of the participants. Compared with the healthy controls (HCs), larger frontoparietal theta and alpha coherence were found in the patients, especially in the right-lateralized hemisphere, which indicated a deficit in attention processing. Moreover, the frontoparietal coherence was positively correlated with altered prolactin (PRL) levels, implying the significance of PRL for adaptive brain compensation in prolactinomas. Taken together, this research showed the variations in attention processing between the HCs and prolactinomas. The coherence between frontal and parietal regions may be one of the possible electrophysiological biomarkers for detecting deficient attention processing in prolactinomas.

The Brain and the Bladder: Forebrain Control of Urinary (In)Continence

Neural circuits extending from the cerebral cortex to the bladder maintain urinary continence and allow voiding when it is socially appropriate. Injuries to certain brain regions produce a specific disruption known as urge incontinence. This neurologic symptom is distinguished by bladder spasticity, with sudden urges to void and frequent inability to maintain continence. The precise localization of neural circuit disruptions responsible for urge incontinence remains poorly defined, partly because the brain regions, cell types, and circuit connections that normally maintain continence are unknown. Here, we review what is known about the micturition reflex circuit and about forebrain control of continence from experimental animal studies and human lesion data. Based on this information, we hypothesize that urge incontinence results from damage to a descending pathway that normally maintains urinary continence. This pathway begins with excitatory neurons in the prefrontal cortex and relays subcortically, through inhibitory neurons that may help suppress reflex micturition during sleep and until it is safe and socially appropriate to void. Identifying the specific cell types and circuit connections that constitute the continence-promoting pathway, from the forebrain to the brainstem, will help us better understand why some brain lesions and neurodegenerative diseases disrupt continence. This information is needed to pave the way toward better treatments for neurologic patients suffering from urge incontinence.

Anatomy and physiology of the lower urinary tract

Functions of the lower urinary tract to store and periodically eliminate urine are regulated by a complex neural control system in the brain, spinal cord, and peripheral autonomic ganglia that coordinates the activity of smooth and striated muscles of the bladder and urethral outlet. Neural control of micturition is organized as a hierarchic system in which spinal storage mechanisms are in turn regulated by circuitry in the rostral brainstem that initiates reflex voiding. Input from the forebrain triggers voluntary voiding by modulating the brainstem circuitry. Many neural circuits controlling the lower urinary tract exhibit switch-like patterns of activity that turn on and off in an all-or-none manner. The major component of the micturition switching circuit is a spinobulbospinal parasympathetic reflex pathway that has essential connections in the periaqueductal gray and pontine micturition center. A computer model of this circuit that mimics the switching functions of the bladder and urethra at the onset of micturition is described. Micturition occurs involuntarily during the early postnatal period, after which it is regulated voluntarily. Diseases or injuries of the nervous system in adults cause re-emergence of involuntary micturition, leading to urinary incontinence. The mechanisms underlying these pathologic changes are discussed.

Lower urinary tract dysfunction in patients with brain lesions

Stroke and brain tumor are well-known brain diseases. The incidence of lower urinary tract dysfunction (LUTD) in these patients ranges from 14% to 53%, mostly overactive bladder (OAB), and is higher when the frontal cortex is involved. This presumably reflects damage at the prefrontal cortex, cingulate cortex, and other areas that regulate (mainly inhibit) the micturition reflex. White-matter disease (WMD) is a chronic, bilateral form of cerebrovascular disease, leading to a high prevalence of OAB (up to 90%). Since WMD is particularly common in the elderly, WMD may be one of the anatomic substrates for elderly OAB. Traumatic brain injury and normal-pressure hydrocephalus are rather diffuse brain diseases, which cause OAB with a prevalence rate of 60-95%. Recent neuroimaging studies have shown a relationship between LUTD and the frontal cortex in these diseases. Data on other brain diseases, particularly affecting deep brain structures, are limited. Small infarctions, tumors, or inflammatory diseases affecting the basal ganglia, hypothalamus, and cerebellum lead to mainly OAB. In contrast, similar diseases affecting the brainstem lead to either OAB or urinary retention. The latter reflects damage at the periaqueductal gray and the pontine micturition center that directly relay and modulate the micturition reflex. Urinary incontinence (UI) in brain disease can be divided into two types: neurogenic UI (due to OAB) and functional UI (immobility and loss of initiative/cognition). These two types of UI may occur together, but management differs significantly. Management of neurogenic UI includes anticholinergic drugs that do not penetrate the blood-brain barrier easily. Management of functional UI includes behavioral therapy (timed/prompted voiding with physical assistance and bladder/pelvic floor training) and drugs to treat gait as well as cognition that facilitate continence. These treatments will maximize the quality of life in patients with brain diseases.

Bladder dysfunction and urodynamic study in tuberculous meningitis

BACKGROUND

Micturitional disturbances in tuberculous meningitis have been reported infrequently and that too without urodynamic studies. Bladder dysfunction in tuberculous meningitis is often considered secondary to tuberculous radiculomyelopathy. We, in this study, evaluated the incidence and pattern of bladder dysfunction in tuberculous meningitis.

MATERIALS AND METHOD

In this prospective study, 51 patients were included. In addition to clinical evaluation, patients were subjected to a urodynamic study along with magnetic resonance imaging (MRI) of brain and spine. Patients were followed up for 6 months. A follow-up urodynamic study was performed after 6 months.

RESULTS

Out of 51 patients, urinary symptoms were present in one-third of the patients. Approximately, 70% (36) of the patients had urodynamic abnormalities. The commonest (22/51) urodynamic abnormality was detrusor hyporeflexia/areflexia. Other urodynamic abnormalities were neurogenic detrusor overactivity in 10, detrusor sphincter dyssynergia in 6, normal detrusor activity in 19, reduced bladder sensation in 12, raised cystometric capacity in 9, and larger volumes of post-void residual urine in 12 patients. Six patients were unable to void on command. Three patients with neurogenic detrusor overactivity had leak during study. MRI showed spinal meningeal enhancement in 37, lumbosacral arachnoiditis in 25, myelitis in 12 patients, CSF loculations in 6, and cord atrophy in 5 patients. Spinal arachnoiditis and urinary symptoms showed significant association with urodynamic abnormalities. Follow-up urodynamic study showed resolution of urodynamic abnormalities in 72.6% of the patients with treatment. Seven (28%) patients, with normal baseline urodynamic findings, paradoxically developed new abnormalities.

CONCLUSION

Bladder dysfunctions, in tuberculous meningitis, are frequently encountered. A significant association exists between urodynamic abnormalities and tuberculous lumbosacral arachnoiditis and myeloradiculopathy.

The micturition switch and its forebrain influences

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

Distinctive clinicopathological features of 2 large families with amyotrophic lateral sclerosis having L106V mutation in SOD1 gene

A clinicopathological study of 2 families with familial amyotrophic lateral sclerosis was previously reported [1]. The present study continues to investigate these families, with detailed clinical, genetic, and neuropathological studies performed on 24 patients, including 5 autopsy cases of the families. A point mutation at codon 106 (L106V) in the copper/zinc superoxide dismutase-1 (SOD1) gene was identified in the families. Average age at onset was 52.0 ± 9.4 years, and initial symptoms were weakness and atrophy in the distal muscles of the lower extremities in most patients. Half of the patients showed neurogenic bladder (overactive bladder) and sensory impairment. The neurophysiological study showed peripheral/central conduction delay. Neuropathological examination revealed severe motor neuron loss with many bizarre reactive astrocytes in the spinal anterior horn. SOD1-immunopositive Lewy body-like hyaline inclusions and aggregation of neurofilaments were observed in the surviving anterior horn cells. Degeneration of the corticospinal tract was relatively minor. In addition, slight but diffuse gliosis was identified in the hypothalamus and medial nucleus of thalamus. Neurogenic bladder, sensory impairment, and degeneration of the hypothalamus and thalamus might be specific features in patients with familial amyotrophic lateral sclerosis with L106V mutation in the SOD1 gene.

Prevalence and risk factors of urinary incontinence in Chinese women: a population-based study

To estimate the current prevalence rate of urinary incontinence (UI) and to identify risk factors in Chinese women, we conducted a population-based survey in 3058 women in Beijing, China, in 2009. The prevalence rate of UI was estimated to be 22.1%, with stress UI (12.9%) being more prevalent than urgency UI (1.7%) and mixed UI (7.5%). The prevalence rates of UI, urgency UI, and mixed UI increased with age, with the highest recorded in participants aged ≥70 years. However, stress UI was most commonly seen in participants aged 50 to 69 years. Risk factors for UI included aging, lower education background, older age of menarche, menstrual disorder, pregnancy history, episiotomy, chronic pelvic pain, gynecological disease, other chronic diseases, constipation, fecal incontinence, lower daily water intake, and frequency of high protein intake. UI is a common disorder in Chinese women, and many risk factors are able to affect the development of UI.

Afferent projections to the pontine micturition center in the cat

The pontine micturition center (PMC) or Barrington's nucleus controls micturition by way of its descending projections to the sacral spinal cord. However, little is known about the afferents to the PMC that control its function and may be responsible for dysfunction in patients with urge-incontinence and overactive bladder. In five female cats, wheatgerm agglutinin-conjugated horseradish peroxidase (WGA-HRP) injections were made in the PMC and adjoining dorsolateral pontine tegmentum. Retrogradely labeled neurons were found in a large area, including the medullary and pontine medial and lateral tegmental field; dorsomedial, lateral, and ventrolateral periaqueductal gray matter (PAG); posterior hypothalamus; medial preoptic area (MPO); bed nucleus of the stria terminalis; central nucleus of the amygdala; and infralimbic, prelimbic, and insular cortices. To verify whether these areas indeed project specifically to the PMC or perhaps only to adjacent structures in the pontine tegmentum, in 67 cats (3)H-leucine or WGA-HRP injections were made in each of these regions. Five cell groups appeared to have direct connections to the PMC, the ventromedial pontomedullary tegmental field, the ventrolateral and dorsomedial PAG, the MPO, and the posterior hypothalamus. The possible functions of these projections are discussed. These results indicate that all other parts of the brain that influence micturition have no direct connection with the PMC.