Endoscopic treatment of vesicoureteral reflux with non-simultaneous involuntary detrusor contraction in chronic spinal cord injury patients with neurogenic detrusor overactivity.

OBJECTIVE: To analyze whether it is correct to use endoscopic treatment via bulking agents of vesicoureteral reflux (VUR) seen on video urodynamics with non-simultaneous involuntary detrusor contraction in chronic spinal cord injury (SCI) patients with neurogenic detrusor overactivity (NDO). METHODS: A retrospective study was performed with a cohort of 76 patients (age 48.9 ± 14.4 years) (mean ± standard deviation) of both sexes with chronic SCI who underwent endoscopic treatment of VUR during the years 2008 to 2011. Patients were subjected to clinical examinations and video urodynamic studies preoperatively and 22 ± 11.4 months after the intervention. RESULTS: Resolution of VUR was achieved in 46 cases (61%). Cured patients had a statistically significant younger age and showed stress urinary incontinence more frequently. On the contrary, a greater grade of VUR, presence of bilateral reflux and presence of NDO were positively associated with treatment failure. The variables that independently influenced the cure of the reflux were NDO and reflux grade. CONCLUSIONS: The failure rate was high in patients with NDO, even though the reflux was not synchronous with involuntary detrusor contraction, and therefore these patients should have NDO eradicated before doing any anti-reflux procedures.

A novel animal model of underactive bladder: analysis of lower urinary tract function in a rat lumbar canal stenosis model.

AIMS: An animal model of neurogenic underactive bladder (UAB) has not been established. It was reported that a rat lumbar spinal canal stenosis (LCS) model created by cauda equina compression manifested intermittent claudication and allodynia. In this study, we examined the lower urinary tract function of the rat LCS model. METHODS: One small hole was drilled at the fifth lumbar vertebral arch (sham), and a rectangular piece of silicone rubber was inserted into the L5-L6 epidural space (LCS). Before and after surgery, a metabolic cage study was performed. After surgery, awake cystometry (CMG) and an in vitro muscle strip study were performed. Bladder morphology was evaluated by hematoxylin and eosin staining. RESULTS: The LCS rats showed a significant decrease in voided volume and a significant increase in postvoid residual volume and residual urine rate compared with Sham rats. CMG showed that the postvoid residual urine volume and numbers of non-voiding contractions significantly increased, while the voided volume, threshold pressure, and maximum intravesical pressure during voiding significantly decreased. There were no significant differences between sham and LCS rats in response to carbachol. In contrast, there was a significant increase in response to field stimulation, especially at lower frequencies, in LCS rats. LCS rats showed no obvious difference in detrusor morphology. CONCLUSIONS: This rat model requires a relatively simple surgical procedure and has characteristics of neurogenic UAB. It seems to be useful in the pathophysiological elucidation of UAB and might have potential for assessment of pharmacotherapy of UAB.

Once-daily trospium chloride 60 mg extended-release provides effective, long-term relief of overactive bladder syndrome symptoms.

AIMS: Once-daily extended-release (XR) trospium chloride has been evaluated for the treatment of overactive bladder syndrome (OAB) in two 12-week randomized, double-blind, placebo-controlled studies. This pooled analysis of the 9-month open-label extensions to these studies evaluated the long-term efficacy and tolerability of trospium XR. METHODS: Following double-blind treatment, subjects with OAB could enter the open-label period, during which they received trospium 60 mg XR once daily for 36 weeks. The primary efficacy variables were changes from baseline in the number of toilet voids and urgency urinary incontinence (UUI) episodes per day at Week 48. Adverse events (AEs) were also recorded. RESULTS: Of the 1,027 subjects who completed double-blind treatment, 944 (92%) continued into the open-label period (placebo-to-trospium, N = 483; trospium-to-trospium, N = 461); 332 (68.7%) and 335 (72.7%), respectively, completed the open-label period. At Week 48, the mean change from baseline in the number of toilet voids/day was -3.21 in the placebo-to-trospium group and -3.35 in the trospium-to-trospium group, and the median change from baseline in the number of UUI episodes/day was -2.33 in both groups. Efficacy was maintained relative to Week 12 in trospium-to-trospium subjects, while improvement was seen following trospium initiation in placebo-to-trospium subjects. Improvement from baseline was also observed on secondary efficacy parameters at Week 48. Trospium was well tolerated; dry mouth and constipation were the most common class treatment-emergent AEs. Central nervous system AEs were rare and did not increase with long-term treatment. CONCLUSIONS: Long-term treatment of OAB with once-daily trospium 60 mg XR is effective and well tolerated.

Chitosan scaffold enhances nerve regeneration within the in vitro reconstructed bladder wall: an animal study.

INTRODUCTION: The function of reconstructed bladder depends on the contracting bladder wall. This can be obtained with a proper innervating segment. Polyglycolic acid (PGA) is used as cell vehicle. Chitosan supported the adhesion and differentiation of neurons. The aim of the study was to compare PGA with PGA/chitosan 'sandwich' grafts for bladder regeneration. METHODS: 3T3 fibroblasts were seeded on 6 PGA and on 3 chitosan scaffolds and incubated for 3 days at 37 degrees C in 5% CO(2) before implantation. Three rats underwent bladder reconstruction with PGA cell-seeded grafts and 3 with PGA grafts covered with chitosan cell-seeded grafts ('sandwich' graft). Three rats in the control group were not operated. After 6 months, reconstructed tissue was stained with hematoxylin and eosin. Neurons were identified by synaptophysin and neuron-specific enolase staining. RESULTS: No complications were noticed. PGA/chitosan grafts were evaluated as (+++) and (++), while PGA grafts were evaluated as (++) and (+) with use of synaptophysin antibody. The control group was evaluated as (+). PGA/chitosan grafts were evaluated as (++) and (+), while PGA grafts were evaluated as (++) and (+) in neuron-specific enolase staining. The control group was evaluated as (+). CONCLUSION: Chitosan improved PGA's abilities as a cell matrix and in guiding neurons into the graft.

Non-traditional management of the neurogenic bladder: tissue engineering and neuromodulation.

Patients with spina bifida and a neurogenic bladder have traditionally been managed with clean intermittent catheterization and pharmacotherapy in order to treat abnormal bladder wall dynamics, protect the upper urinary tract from damage, and achieve urinary continence. However, some patients will fail this therapy and require surgical reconstruction in the form of bladder augmentation surgery using reconfigured intestine or stomach to increase the bladder capacity while reducing the internal storage pressure. Despite functional success of bladder augmentation in achieving a low pressure reservoir, there are several associated complications of this operation and patients do not have the ability to volitionally void. For these reasons, alternative treatments have been sought. Two exciting alternative approaches that are currently being investigated are tissue engineering and neuromodulation. Tissue engineering aims to create new bladder tissue for replacement purposes with both "seeded" and "unseeded" technology. Advances in the fields of nanotechnology and stem cell biology have further enhanced these tissue engineering technologies. Neuromodulation therapies directly address the root of the problem in patients with spina bifida and a neurogenic bladder, namely the abnormal relationship between the nerves and the bladder wall. These therapies include transurethral bladder electrostimulation, sacral neuromodulation, and neurosurgical techniques such as selective sacral rhizotomy and artificial somatic-autonomic reflex pathway construction. This review will discuss both tissue engineering techniques and neuromodulation therapies in more detail including rationale, experimental data, current status of clinical application, and future direction.

Effects of liposome-based local suppression of nerve growth factor in the bladder on autonomic dysreflexia during urinary bladder distention in rats with spinal cord injury.

PURPOSE: To examine (1) whether spinal cord injury (SCI) time-dependently increases the severity of autonomic dysreflexia (AD) and expression levels of bladder nerve growth factor (NGF) protein, and (2) whether local suppression of NGF in the bladder improves SCI-induced AD in rats. MATERIALS AND METHODS: SCI was produced by the transection of the T2/3 spinal cord in female Sprague-Dawley rats. At 4 or 8weeks after SCI, differences in the mean arterial blood pressure (ΔMAP) and heart rate (ΔMHR) during graded increases in intravesical pressure to 20, 40 and 60cm H2O from those before bladder distention and NGF protein levels in the bladder wall were evaluated in spinal intact and SCI rats under urethane anesthesia. Seven weeks after SCI liposome-NGF antisense conjugates were administered intravesically to the animals. At 1week after intravesical treatment (8weeks after SCI), ΔMAP and ΔMHR during bladder distention and bladder NGF protein expression were evaluated. RESULTS: The ΔMAP and ΔMHR were increased in a graded manner in response to bladder distention at intravesical pressures of 20, 40 and 60cm H2O in SCI rats. These AD-like cardiovascular responses and NGF protein expression in the bladder mucosal and muscle layers were increased after SCI in a time-dependent manner. The liposome-NGF antisense treatment significantly reduced the NGF protein overexpression in the mucosal layer of SCI rat bladder and reduced ΔMAP and ΔMHR elicited by bladder distention. CONCLUSIONS: These results indicate that the duration of the post-SCI recovery period affects the severity of AD induced by bladder distention as well as the level of bladder NGF protein, and that local suppression of NGF expression in the bladder reduces SCI-induced AD. Thus, Intravesical application of liposome-NGF antisense conjugates can be a new effective therapy for bladder distention-induced AD after SCI.

Characterization of iridium film as a stimulating neural electrode.

Iridium films having near-bulk properties were formed by electron-beam evaporation with simultaneous bombardment of Ar ion beam. The charge-injection capabilities of Ir film were investigated, and the detrusor pressure induced by S2 stimulation with Ir-coated Pt electrode was measured and compared with the uncoated Pt electrode. The charge densities of Ir film were continuously increased with increase in the number of cycles in 0.1 M H2SO4 due to the accumulation of the iridium oxide phase. The iridium oxide formed contained nano-pores, and oxides had different dielectric properties. The Ir film could inject various amounts of charge in physiological solution under the identical stimulating condition depending on the degree of activation in 0.1 M H2SO4. S2 stimulation by Ir-coated Pt electrode caused more efficient bladder contraction of the male dog than the uncoated Pt electrode under the identical stimulus condition.

Silicone-gel prosthesis in treatment of urinary incontinence secondary to neurogenic bladder dysfunction.

Patients with lower neuron lesion neurogenic bladder, with normal upper urinary tracts, poor closing pressure of the urethra, and absence of vesicoureteral reflux can be considered candidates for the insertion of the silicone-gel (Kaufman) prosthesis. Our results in 10 cases indicated that there is a place for passive urethral compression in the treatment of neurogenic bladder after a careful selection of patients and using objective methods to regulate the amount of urethral compression. The use of a combined operation (silicone-gel prosthesis and a Small-Carrion prosthesis) in some of the cases is also presented.

Muscarinic receptor subtypes modulating smooth muscle contractility in the urinary bladder.

Normal physiological voiding as well as generation of abnormal bladder contractions in diseased states is critically dependent on acetylcholine-induced stimulation of contractile muscarinic receptors on the smooth muscle (detrusor) of the urinary bladder. Muscarinic receptor antagonists are efficacious in treating the symptoms of bladder hyperactivity, such as urge incontinence, although the usefulness of available drugs is limited by undesirable side-effects. Detrusor smooth muscle is endowed principally with M2 and M3 muscarinic receptors with the former predominating in number. M3 muscarinic receptors, coupled to stimulation of phosphoinositide turnover, mediate the direct contractile effects of acetylcholine in the detrusor. Emerging evidence suggests that M2 muscarinic receptors, via inhibition of adenylyl cyclase, cause smooth muscle contraction indirectly by inhibiting sympathetically (beta-adrenoceptor)-mediated relaxation. In certain diseased states, M2 receptors may also contribute to direct smooth muscle contraction. Other contractile mechanisms involving M2 muscarinic receptors, such as activation of a non-specific cationic channel and inactivation of potassium channels, may also be operative in the bladder and requires further investigation. From a therapeutic standpoint, combined blockade of M2 and M3 muscarinic receptors would seem to be ideal since this approach would evoke complete inhibition of cholinergically-evoked smooth muscle contractions. However, if either the M2 or M3 receptor assumes a greater pathophysiological role in disease states, then selective antagonism of only one of the two receptors may be the more rational approach. The ultimate therapeutic strategy is also influenced by the extent to which pre-junctional M1 facilitatory and M2 inhibitory muscarinic receptors regulate acetylcholine release and also which subtypes mediate the undesirable effects of muscarinic receptor blockade such as dry mouth. Finally, the consequence of muscarinic receptor blockade in the central nervous system on the micturition reflex, an issue which is poorly studied and seldom taken into consideration, should not be ignored.

Oxybutynin. A review of its pharmacodynamic and pharmacokinetic properties, and its therapeutic use in detrusor instability.

Oxybutynin possesses anticholinergic and spasmolytic properties, which together form the basis for its use as a therapeutic option in patients with overactive detrusor function--either idiopathic detrusor instability (DI) or detrusor hyperreflexia. Of the symptoms of detrusor overactivity, urge incontinence is often the most distressing to the patient. Urge incontinence and other subjective parameters (urinary frequency, urgency) improve in tandem with objective (cystometric) measures (maximum detrusor pressure during filling, volume at first desire to void, maximum bladder capacity) in ambulatory, including elderly, patients treated with oxybutynin. However, on the basis of results of limited investigations, the drug appears ineffective in elderly institutionalised individuals. Relative to other anticholinergic drugs, oxybutynin appears at least as effective as propantheline and similar in efficacy to propiverine in small trials, although these results are not definitive. Further investigation of intravesical oxybutynin may lead to this route becoming an option in patients with pre-existing catheters. Adverse effects--dry mouth, constipation, blurred vision--related to the anticholinergic activity of oxybutynin occur frequently and can be sufficiently troublesome to necessitate treatment discontinuation in up to 25% of patients, depending on the dosage. Increases in residual urine volume suggesting urinary retention (undesirable in patients with idiopathic DI), also can develop in some oxybutynin recipients. In summary, oxybutynin is one of the few drugs proven to be beneficial in some patients with overactive detrusor function. Despite the occurrence of unwanted anticholinergic effects in many patients, and apparent lack of efficacy in the elderly institutionalised population, oxybutynin should be considered for the drug of first choice in patients with detrusor overactivity, including the elderly ambulatory population, when pharmacological therapy is indicated.

The male rectourethralis and deep transverse perineal muscles and their relationship to adjacent structures examined with successive slices of celloidin-embedded pelvic viscera.

BACKGROUND: The precise relationship of the structures dorsal to the membranous urethra, including the rectourethralis muscle, the rhabdosphincter, the deep transverse perineal muscle (DTPM), the perineal body, and Denonvillier's fascia, remains controversial. OBJECTIVE: Our aim was to reexamine the detailed anatomy of the rectourethralis muscle and the deep transverse perineal muscle and their relationship with adjacent structures. DESIGN, SETTING, AND PARTICIPANTS: The pelvic viscera, including bladder, prostate, and rectum, were obtained from 20 formalin-fixed adult male cadavers. MEASUREMENTS: The pelvic viscera were embedded in celloidin and then cut into successive slices with an immersing-alcohol microtome. All slices were explored with anatomic microscopy. RESULTS AND LIMITATIONS: The longitudinal muscle of the anterior rectal wall was divided into anterior and posterior bundles at the junction of the rectum and anal canal. The intermediate fibers of the anterior bundle ended at the perineal body. The lateral fibers of the anterior bundle terminated at the posterior connective tissue of the bulbus penis. The DTPM occupied the space between the rhabdosphincter, rectum, and the bilateral levator ani muscle. Denonvillier's fascia terminated at the junction of the prostate and rhabdosphincter. Numerous slender nerves coming from the neurovascular bundle perforated the DTPM. CONCLUSIONS: The anterior bundle of the longitudinal muscle of the rectum inserts into the bulbus penis forming the rectourethralis muscle and ends at the perineal body forming the rectoperinealis muscle. The anterior bundle and DTPM together may contribute to the rectal angle of the anterior rectal wall, and they support the posterior border of the rhabdosphincter.

Evaluation of direct bladder stimulation with stainless steel woven eye electrodes.

Encouraged by recent clinical reports of micturition induced in patients by direct bladder stimulation, we conducted a study of optimum methods of direct bladder stimulation. During surgery six male cats received eight large surface-area woven eye electrodes sutured to the bladder wall serosa, four on the bladder dome and four adjacent to the trigone area. Two additional small surface-area single knot electrodes were sutured in the trigone area. Suprapubic and intraperitoneal tubes were placed for pressure recording and bladder filling. Leg and pelvic floor EMG electrodes were also used for tethered recordings. One to eight weeks after surgery, optimum stimulation methods were evaluated as the animal freely moved about a urodynamic recording cage. Electrodes in the trigone region were more effective than electrodes on the dome and induced bladder contractions and voiding similar to spontaneously induced voiding with bladder filing. Large surface area, woven eye electrodes, composed of multistranded 316LVM stainless steel wire, were more effective than smaller surface area single knot electrodes. High stimulating frequencies (40 Hz) were better than lower frequencies (10 to 20 Hz), and a 1 millisecond pulse duration was optimal. Pulsing with stimulating currents from 10 to 25 mA induced effective bladder contractions with voiding when applied for 3 seconds. However, lower currents using longer stimulation periods were also effective. Bipolar electrodes with both electrodes on the bladder wall were superior to monopolar arrangements with the positive ground electrode along the animal's back. We concluded that in the able-bodied cat model, bladder contractile activity for micturition can be induced with direct bladder stimulation and with little discomfort. An effective stimulation protocol consists of capacitor-coupled monophasic pulses with large surface area bipolar electrodes in the trigone region. Stimulating parameters of 40 Hz, 1 msec., 10 to 25 mA applied for 3 seconds were optimal. In addition, based on corrosion resistance observations, the electrodes are quite suitable for long-term studies.

[Pathophysiology of the overactive bladder and its pharmacological treatment].

This paper reviews the possible mechanisms underlying bladder overactivity and discusses the targets for pharmacological treatment of this disorder. Damage to the brain (cerebrovascular disease, etc.) induces bladder overactivity by reducing suprapontine inhibition. Currently, attention has focused on C-fiber bladder afferents that may concern the mechanisms for bladder overactivity resulting from various etiologies such as spinal cord lesions, bladder outlet obstruction and bladder hypersensitivity disorders. With regard to the pathophysiology of idiopathic overactive bladder, both myogenic and neurogenic mechanisms may be involved in involuntary detrusor contraction. Since an intravesical capsaicin or resiniferatoxin was shown to have favorable therapeutic effects, afferent C-fiber neurons become a new target for pharmacological treatment. C-fiber neurons are known to contain tachykinins and other peptides as neurotransmitters. When released, tachykinins can influence via NK receptors bladder activity. In addition, evidences suggest that ATP receptors (P2X3) and prostaglandin receptors in afferent C-fiber neurons may play a role in mediating bladder overactivity. Thus, NK-antagonist, P2X3-antagonist and PG receptor-antagonist may be potential therapeutic drugs in the near future. beta 3-Adrenoceptor agonist is an another candidate drug for the treatment of the overactive bladder. Finally, it is important to notice that in any etiology including an idiopathic one, antimuscarinic drugs can improve bladder overactivity, although dry mouth and constipation are inevitable side-effects.

An epidemic of urinary retention caused by dimethylaminopropionitrile.

An epidemic of urinary retention among workers in a polyurethane manufacturing plant was discovered in the spring of 1978. The most severely affected workers had neurogenic bladders confirmed by cystometrograms and mild sensory peripheral neuropathy. A survey of the plant disclosed increased incidence of urinary retention, muscle weakness, paresthesia, insomnia, and sexual dysfunction in exposed workers. A catalyst containing dimethylaminopropionitrile was identified as the probable causative agent, and after its removal no new cases occurred.

Intravesical therapy options for neurogenic detrusor overactivity.

STUDY DESIGN: Review article. SETTING: Neuro-Urology, Spinal Cord Injury Center, Balgrist University Hospital, Zurich, Switzerland. OBJECTIVES: This review considers intravesical treatment options of neurogenic detrusor overactivity and discusses the underlying mechanism of action, clinical safety and efficacy, and the future trends. METHODS: The available literature was reviewed using medline services. RESULTS: Oral anticholinergic drugs are widely used to treat detrusor overactivity, but they are ineffective in some patients or cause systemic side effects such as blurred vision or dry mouth. As an alternative, topical therapy strategies have been suggested to achieve a profound inhibition of the overactive detrusor and to avoid high systemic drug levels. Currently available intravesical treatment options either act on the afferent arc of the reflex such as local anaesthetics or vanilloids or on the efferent cholinergic transmission to the detrusor muscle such as intravesical oxybutynin or botulinum toxin. Although an established and effective therapy, intravesical oxybutynin is not widely used. Evidence for clinical significance of intravesical atropine and local anaesthetic is missing. Intravesical capsaicin has been shown to improve clinical and urodynamic parameters, but cause pain in some patients. The intravesical instillation of resiniferatoxin and the injection of botulinum-A toxin into the detrusor muscle are promising new options; however, randomised placebo-controlled studies to prove their safety and efficacy are still missing. CONCLUSION: Intravesical treatment strategies in patients with neurogenic detrusor overactivity may provide alternatives to established therapies such as oral anticholinergics. The selectivity of the intravesical treatment and the reduction or even the absence of side effects are major advantages of this topical approach.

Efficacy and safety of propiverine in SCI-patients suffering from detrusor hyperreflexia--a double-blind, placebo-controlled clinical trial.

AIMS OF THE STUDY: The aim of this double-blind, randomised, prospective, multicentre trial was to evaluate the efficacy of propiverine in patients suffering from detrusor hyperreflexia caused by spinal cord injury in comparison to placebo. STUDY DESIGN: The treatment period of 14 days comprised visits at baseline (V1) and after 14 days treatment (V2). Fifteen mg propiverine t.i.d. or placebo t.i.d. were administered as medication. The following efficacy parameters were adopted: the urodynamic parameters maximal cystometric bladder capacity, bladder volume on onset of the first as well as duration and amplitude of the maximum detrusor contraction, bladder compliance and residual urine, and subjective assessment of efficacy by physicians. For the evaluation of the safety of propiverine the incidence rate of adverse events by directly questioning as well as laboratory parameters were investigated. For biometrical evaluation t-test for independent groups was applied. RESULTS: One hundred and thirteen patients were investigated. The maximal cystometric bladder capacity increased significantly in the propiverine group, on average by 104 ml (V1: 262+/-132 ml. V2: 366+/-143 ml, P<0.001). The changes in bladder capacity during the first contraction and the maximum detrusor contraction in the verum group were both statistically significant. The bladder compliance documented a more pronounced increase under propiverine in comparison to placebo. Residual urine increased by 37+/-71 ml in the propiverine group, significantly more than in the placebo group (P=0.01). Sixty-three per cent of the patients expressed subjectively an improvement under propiverine in comparison with 23% of the placebo group. Expected anticholinergic adverse events occurred: dryness of the mouth (37% in the verum and 8% in the placebo group), accommodation disorders (28% and 2% respectively). Nausea, constipation, headache, dizziness, tiredness and palpitations were reported in almost comparable incidence rates between 3 and 13% in both treatment groups. Eight drop-outs were registered in the propiverine group (five due to adverse events) and three in the placebo group (one due to adverse events). The laboratory parameters revealed no changes. CONCLUSION: Propiverine proved its efficacy in detrusor hyperreflexia with regard to the urodynamic parameters of the maximal cystometric bladder capacity and detrusor contractility. Anticholinergic adverse events such as dryness of the mouth and accommodation disorders were considered being tolerable. The increase in residual urine reflects the therapeutically desired effect of detrusor relaxation because the majority of patients normally practise intermittent catheterisation for bladder emptying.