Pudendal Nerve Stimulation Research Articles

ID: 325822 Computational modelling of interpatient differences in neural recruitment during pudendal nerve stimulation

ID: 325822 Computational modelling of interpatient differences in neural recruitment during pudendal nerve stimulation

3 - First in human exploratory study of adaptive pudendal nerve stimulation in women with refractory urge or mixed urinary incontinence: short term results in 11 patients.

3 - First in human exploratory study of adaptive pudendal nerve stimulation in women with refractory urge or mixed urinary incontinence: short term results in 11 patients.

Endovascular stimulation of the pudendal nerve using a stent-mounted electrode array

Objective. Previous preclinical and clinical studies have demonstrated that pudendal nerve is a promising target for restoring bladder control. The spatial proximity between the pudendal nerve and its accompanying blood vessels in the pudendal canal provides an opportunity for endovascular neurostimulation, which is a less invasive approach compared to conventional chronically implanted electrodes. In this study, we investigated the feasibility of excitatory stimulation and kilohertz-frequency block of the compound pudendal nerve in sheep using a stent-mounted electrode array.Approach. In a set of acute animal experiments, a commercially available hexapolar electrode catheter was introduced in the unilateral internal pudendal artery to deliver bipolar electrical stimulation of the adjacent compound pudendal nerve. The catheter electrode was replaced with a custom-made stent-mounted electrode array and the stimulation sessions were repeated. Global electromyogram activity of the pelvic floor and related sphincter muscles was recorded with a monopolar electrode placed within the urethra concurrently.Main results. We demonstrated the feasibility of endovascular stimulation of the pudendal nerve with both electrode types. The threshold current of endovascular stimulation was influenced by electrode-nerve distance and electrode orientation. Increasing the axial inter-electrode distance significantly decreased threshold current. Endovascular kilohertz-frequency nerve block was possible with the electrode catheter.Significance. The present study demonstrated that endovascular stimulation of the pudendal nerve with the stent-mounted electrode array may be a promising less invasive alternative to conventional implantable electrodes, which has important clinical implications in the treatment of urinary incontinence. Endovascular blocking of pudendal nerve may provide an alternative solution to the bladder-sphincter dyssynergia problem in bladder management for people with spinal cord injury.

Biofeedback combined with percutaneous electrical pudendal nerve stimulation for the treatment of low anterior rectal resection syndrome: a study protocol for a randomized controlled trial

BackgroundLow anterior resection syndrome (LARS) is a distressing condition that affects approximately 25–80% of patients following surgery for rectal cancer. LARS is characterized by debilitating bowel dysfunction symptoms, including fecal incontinence, urgent bowel movements, and increased frequency of bowel movements. Although biofeedback therapy has demonstrated effectiveness in improving postoperative rectal control, the research results have not fulfilled expectations. Recent research has highlighted that stimulating the pudendal perineal nerves has a superior impact on enhancing pelvic floor muscle function than biofeedback alone. Hence, this study aims to evaluate the efficacy of a combined approach integrating biofeedback with percutaneous electrical pudendal nerve stimulation (B-PEPNS) in patients with LARS through a randomized controlled trial (RCT).Methods and analysisIn this two-armed multicenter RCT, 242 participants with LARS after rectal surgery will be randomly assigned to undergo B-PEPNS (intervention group) or biofeedback (control group). Over 4 weeks, each participant will undergo 20 treatment sessions. The primary outcome will be the LARS score. The secondary outcomes will be anorectal manometry and pelvic floor muscle electromyography findings and the European Organization for the Research and Treatment of Cancer Quality of Life Questionnaire-Colorectal 29 (EORTC QLQ-CR29) scores. Data will be collected at baseline, post-intervention (1 month), and follow-up (6 months).DiscussionWe anticipate that this study will contribute further evidence regarding the efficacy of B-PEPNS in alleviating LARS symptoms and enhancing the quality of life for patients following rectal cancer surgery.Trial registrationChinese Clincal Trials Register ChiCTR2300078101. Registered 28 November 2023.

Adrenergic relaxations in an in situ urinary bladder model evoked by stimulation of sensory pelvic and pudendal nerves in the rat

Urinary bladder dysfunction might be related to disturbances at different levels of the micturition reflex arc. The current study aimed to further develop and evaluate a split bladder model for detecting and analysing relaxatory signalling in the rat urinary bladder. The model allows for discrimination between effects at the efferent and the afferent side of the innervation. In in vivo experiments, the stimulation at a low frequency (1 Hz) of the ipsilateral pelvic nerve tended to evoke relaxation of the split bladder half (contralateral side; −1.0 ± 0.4 mN; n = 5), in contrast to high frequency-evoked contractions. In preparations in which the contralateral pelvic nerve was cut the relaxation occurred at a wider range of frequencies (0.5–2 Hz). In separate experiments, responses to 1 and 2 Hz were studied before and after intravenous injections of propranolol (1 mg/kg IV). The presence of propranolol significantly shifted the relaxations into contractions. Also, electrical stimulation of the ipsilateral pudendal nerve evoked relaxations of similar magnitude as for the pelvic stimulations, which were also affected by propranolol. In control in vitro experiments, substances with β-adrenoceptor agonism, in contrast to a selective α-agonist, evoked relaxations. The current study shows that the split bladder model can be used for in vivo studies of relaxations. In the model, reflex-evoked sympathetic responses caused relaxations at low intensity stimulation. The involvement of β-adrenoceptors is supported by the sensitivity to propranolol and by the in vitro observations.

Role of opioid and β-adrenergic receptors in bladder underactivity induced by prolonged pudendal nerve stimulation in cats.

To determine the role of opioid and β-adrenergic receptors in bladder underactivity induced by prolonged pudendal nerve stimulation (PNS). In α-chloralose anesthetized cats, 30-min PNS was applied repeatedly for 3-9 times to induce poststimulation or persistent bladder underactivity. Then, naloxone (opioid receptor antagonist, 1 mg/kg, IV) or propranolol (β-adrenergic receptor antagonist, 3 mg/kg, IV) was given to reverse the bladder underactivity. After the drug treatment, an additional 30-min PNS was applied to counteract the drug effect. Repeated cystometrograms were performed by slowly (1-2 mL/min) infusing the bladder with saline via a urethral catheter to determine the bladder underactivity and the treatment effects. Prolonged (2-4.5 h) PNS induced bladder underactivity evident as a large bladder capacity (169 ± 49% of control) and a reduced amplitude of bladder contraction (59 ± 17% of control). Naloxone fully reversed the bladder underactivity by reducing bladder capacity to 113 ± 58% and increasing the amplitude of bladder contraction to 104 ± 34%. After administration of naloxone an additional 30-min PNS temporarily increased the bladder capacity to the underactive bladder level (193 ± 74%) without changing the amplitude of the bladder contraction. Propranolol had no effect on bladder underactivity. A tonic enkephalinergic inhibitory mechanism in the CNS plays a critical role in the bladder underactivity induced by prolonged PNS, while the peripheral β-adrenergic receptor mechanism in the detrusor is not involved. This study provides basic science evidence consistent with the clinical observation that comorbid opioid usage may contribute to voiding dysfunction in patients with Fowler's syndrome.

ID: 215134 Interpatient Variability in Neural Recruitment During Pudendal Nerve Stimulation - A Patient-Specific Computational Modeling Study

Pudendal nerve (PN) stimulation is an emerging neuromodulation technique for the treatment of refractory bladder dysfunction and pelvic pain, conditions affecting the quality-of-life and productivity of millions of individuals around the world. The PN is a mixed nerve originating from the S2-S4 sacral nerve roots and innervating the genital, perineal, and rectal regions. Although it has been studied extensively in preclinical settings, limited studies of PN stimulation have been performed in human subjects, and interpatient variability in outcomes are not well understood. Therefore, we created patient-specific computational models to study neural recruitment in human subjects undergoing PN stimulation as part of their clinical care.

72 - Intraneural pudendal nerve recording and stimulation in animal models for the closed-loop control of lower urinary tract dysfunction

72 - Intraneural pudendal nerve recording and stimulation in animal models for the closed-loop control of lower urinary tract dysfunction

Pudendal Nerve Block by Adaptively Stepwise Increasing the Intensity of High-Frequency (10 kHz) Biphasic Stimulation

ObjectiveThe purpose of this study is to determine whether adaptively stepwise increasing the intensity of a high-frequency (10 kHz) biphasic stimulation (HFBS) can produce nerve conduction block without generating a large initial response. Materials and MethodsIn anesthetized cats, three cuff electrodes were implanted on the left pudendal nerve for stimulation or block. The urethral pressure increase induced by pudendal nerve stimulation was used to measure the pudendal nerve block induced by HFBS. ResultsHFBS applied suddenly with a large step increase in intensity induced a large (86 ± 16 cmH2O) urethral pressure increase before it blocked pudendal nerve conduction. However, HFBS applied by adaptively stepwise increasing the intensity every 10 to 60 seconds over a long period (33–301 minutes; average 108 ± 35 minutes) with many small intensity increases (0.005–0.1 mA) induced no response or low-amplitude high-frequency urethral pressure changes before it blocked pudendal nerve conduction. The minimal HFBS intensities required by the two different methods to block pudendal nerve conduction are similar. ConclusionThis study is important for better understanding the possible mechanisms underlying the HFBS-induced nerve block and provides the possibility of developing a new nerve block method for clinical applications in which an initial large response is a concern.

MP52-09 PUDENDAL NEUROMODULATION IN SPINA BIFIDA PATIENTS WITH NEUROGENIC BLADDER AND BOWEL DYSFUNCTION

You have accessJournal of UrologyCME1 Apr 2023MP52-09 PUDENDAL NEUROMODULATION IN SPINA BIFIDA PATIENTS WITH NEUROGENIC BLADDER AND BOWEL DYSFUNCTION Hailey Eisner, Bernadette Zwaans, Priya Padmanabhan, and Kenneth Peters Hailey EisnerHailey Eisner More articles by this author , Bernadette ZwaansBernadette Zwaans More articles by this author , Priya PadmanabhanPriya Padmanabhan More articles by this author , and Kenneth PetersKenneth Peters More articles by this author View All Author Informationhttps://doi.org/10.1097/JU.0000000000003300.09AboutPDF ToolsAdd to favoritesDownload CitationsTrack CitationsPermissionsReprints ShareFacebookLinked InTwitterEmail Abstract INTRODUCTION AND OBJECTIVE: Spina bifida is a congenital defect resulting in incomplete closure of the neural tube in the sacrum. It is the primary cause of congenital urinary dysfunction with symptoms ranging from frequency, urgency and urge incontinence to urinary retention. Patients often have concomitant bowel dysfunction with both constipation and fecal incontinence resulting in a significantly decreased quality of life. Because of the resulting sacrococcygeal deformity typical techniques for placement of a tined lead at the S3 foramen are ineffective. Neuromodulation has long been used to treat bladder and bowel dysfunction and evidence suggests that pudendal neuromodulation has a role in the treatment of symptoms secondary to spinal pathology. Our objective was to assess the effectiveness of pudendal neuromodulation in treating bowel and lower urinary tract symptoms (LUTS) in spina bifida. METHODS: We investigated the effect of pudendal nerve stimulation on LUTS and bowel symptoms in four spina bifida patients. All four patients failed behavioral modification and anticholinergics. They underwent staged neuromodulation with placement of a tined lead at the pudendal nerve for the treatment of refractory LUTS and bowel symptoms. Relevant medical history, physical exams, symptoms prior to treatment and symptom improvement were assessed. RESULTS: One male and three female patients with a mean age of 45.8 years (39-53) were included in the study. Mean follow-up was 68 months (43-83). All three females had urgency, frequency, urge incontinence and fecal incontinence at baseline. At the most recent follow-up, all have maintained a clinical improvement of more than 50% for all symptoms compared with baseline. The male patient, with urinary retention prior to treatment, reported improved bladder sensation yet did not have improvement in intermittent catheterization volumes. CONCLUSIONS: A 2022 SUFU white paper described the potential risk of dementia in anticholinergic dependent spina bifida patients. The 2021 AUA/SUFU guidelines recommended against sacral neuromodulation in this population due to sacral deformities. Pudendal neuromodulation is a promising treatment for patients with both bowel and bladder symptoms secondary to spina bifida. More research is needed to elucidate this potential and will help to expand the indications for pudendal neuromodulation and neuromodulation in potential alternative locations. Source of Funding: none © 2023 by American Urological Association Education and Research, Inc.FiguresReferencesRelatedDetails Volume 209Issue Supplement 4April 2023Page: e706 Advertisement Copyright & Permissions© 2023 by American Urological Association Education and Research, Inc.MetricsAuthor Information Hailey Eisner More articles by this author Bernadette Zwaans More articles by this author Priya Padmanabhan More articles by this author Kenneth Peters More articles by this author Expand All Advertisement PDF downloadLoading ...

Efficacy of electrical pudendal nerve stimulation versus pelvic floor muscle training in treating postradical prostatectomy urinary incontinence: study protocol for a randomised controlled trial

IntroductionUrinary incontinence (UI) is one of the main complications of radical prostatectomy. Electrical pudendal nerve stimulation (EPNS) has been used to treat stress UI based on its mechanism of passive...

Pudendal, but not tibial, nerve stimulation modulates vulvar blood perfusion in anesthetized rodents.

Preclinical studies have shown that neuromodulation can increase vaginal blood perfusion, but the effect on vulvar blood perfusion is unknown. We hypothesized that pudendal and tibial nerve stimulation could evoke an increase in vulvar blood perfusion. We used female Sprague-Dawley rats for non-survival procedures under urethane anesthesia. We measured perineal blood perfusion in response to 20-minute periods of pudendal and tibial nerve stimulation using laser speckle contrast imaging (LSCI). After a thoracic-level spinalization and a rest period, we repeated each stimulation trial. We calculated average blood perfusion before, during, and after stimulation for three perineal regions (vulva, anus, and inner thigh), for each nerve target and spinal cord condition. We observed a significant increase in vulvar, anal, and inner thigh blood perfusion during pudendal nerve stimulation in spinally intact and spinalized rats. Tibial nerve stimulation had no effect on perineal blood perfusion for both spinally intact and spinalized rats. This is the first study to examine vulvar hemodynamics with LSCI in response to nerve stimulation. This study demonstrates that pudendal nerve stimulation modulates vulvar blood perfusion, indicating the potential of pudendal neuromodulation to improve genital blood flow as a treatment for women with sexual dysfunction. This study provides further support for neuromodulation as a treatment for women with sexual arousal disorders. Studies in unanesthetized animal models ofgenital arousal disorders are needed to obtain further insights into the mechanisms of neural control over genital hemodynamics.

Neuromodulation possibilities in neurogenic lower urinary tract dysfunction

Introduction. Neuromodulation has proven itself in the treatment of patients suffering from idiopathic overactive bladder and non-obstructive urinary retention, who are resistant to conservative therapy. The possible use of the method in the population of patients with neurogenic lower urinary tract dysfunction (NLUTD) is of undoubted clinical interest.Objective. To analyze the current possibilities and features of neuromodulation in a cohort of patients with NLUTD.Materials and methods. Original research materials published in the PubMed, eLibrary, SciVerse (ScienceDirect), Scopus, Medline, EMBASE databases, websites of professional associations without restrictions on the date of publication were used. Sixty sources were selected for citation, with preference given to systematic reviews, meta-analyses and RCTs .Results. In relation to NLUTD, transcranial and peripheral magnetic stimulation, intravesical electrical stimulation, tibial, pudendal electrical stimulation, and stimulation of the dorsal pudendal nerve, as well as sacral and epidural methods of neurostimulation are considered.Conclusion. The current literature optimistically presents the experience of using neuromodulation in the NLUTD patient population with the largest evidence base for invasive sacral and tibial stimulation. The studies are based on heterogeneous populations, limited by small sample sizes with insufficient descriptive part of the degree and severity of neurological diseases, and it should be considered when forming guidelines. However, the lack of other suitable therapies and promising initial results indicate the importance of further efforts to improve the applied methods of neuromodulation. Further studies are needed with larger sample sizes, better classification of diseases, and controlled study design

Neuromodulation for Management of Chronic Pelvic Pain: A Comprehensive Review.

Chronic pelvic pain (CPP) is a symptom that derives from a complex group of heterogeneous pathologies of the pelvic organs. The aim of this study was to review the available evidence on efficacy of neuromodulatory modalities including sacral neuromodulation, dorsal root ganglion stimulation, dorsal column neuromodulation, and pudendal nerve stimulation. This narrative review focuses on updated information on neuromodulation for management of chronic pelvic pain. In 2022, we searched English-language studies on neuromodulation, pelvic pain, and chronic pain in a comprehensive search. We searched the following databases: PubMed, Medline, SciHub, Cochrane Database of Systematic Reviews, and Google Scholar. We used the following combinations of keywords: neuromodulation, pelvic pain, chronic pain, chronic pelvic pain, pelvic pain treatment. We tried to include as many recent manuscripts as possible (within the last 3years) but also included papers older than 3years if they were particularly relevant to our topic. We also attempted to search for, use, and cite primary manuscripts whenever possible. CPP is a challenging entity to treat because of diagnostic inconsistencies and limited evidence for therapeutic modalities. Our review found evidence suggestive of benefit for all modalities reviewed but the data was of overall low quality with numerous limitations. The literature highlights a lack of randomized controlled trials for neuromodulatory therapies but suggests a growing role for such techniques in treating refractory chronic pelvic pain syndrome (CPPS). This review explores the available evidence on efficacy of neuromodulatory modalities for CPPS and contextualizes the results with information about the type of neuromodulation, lead location and waveform, pain outcomes and assessment timepoints, and reported adverse effects.

Vaginal Lubrication and Pressure Increase Induced by Pudendal Nerve Stimulation in Cats

Vaginal lubrication and contractions are among the top difficulties affecting sexual intercourse in women after spinal cord injury. This study aimed at determining if pudendal nerve stimulation (PNS) can improve vaginal lubrication and induce increases in vaginal pressure. In anesthetized cats, a small piece of cotton was inserted into the vagina for 10 minutes with or without PNS to measure vaginal wetness by the weight increase of the vaginal cotton. Then, a small balloon catheter was inserted into the vagina to measure the pressure increase induced by PNS. Intensity response of the vagina to PNS (30 Hz, 0.2 ms, 5 seconds) was determined at 1-4 times of intensity threshold (T) for PNS to induce an observable vaginal pressure increase. Frequency response was determined at 2T intensity in a range of PNS frequencies (5-50 Hz). Finally, fatigue in vaginal pressure was determined by applying PNS (30 Hz, 2T) either continuously or intermittently (5 seconds on and 5 seconds off) for 4 minutes. The effectiveness of PNS in increasing vaginal wetness and pressure is evaluated. PNS significantly (P=.0327) increased the measurement of vaginal wetness from 15.8 ± 3.8 mg during control without stimulation to 32.4 ± 4.7 mg after stimulation. Vaginal pressure increased as PNS intensity or frequency increased. PNS (30 Hz, 2T) induced vaginal pressure increase ≥80% of the maximal response. Intermittent PNS induced significantly (P=.0354) smaller fatigue (45.6 ± 3.7%) in vaginal pressure than continuous PNS (69.1 ± 3.0%) during the 4-minute stimulation. This study raises the possibility of developing a novel pudendal neuromodulation device to improve female sexual function after spinal cord injury. This study provides preclinical data supporting the development of a novel pudendal neuromodulation device. The limitation includes the lack of chemical analysis of the vaginal secretion. PNS can improve vaginal lubrication and induce increases in vaginal pressure. Chen J, Zhong Y, Wang J, et al. Vaginal Lubrication and Pressure Increase Induced by Pudendal Nerve Stimulation in Cats. J Sex Med 2022;19:1517-1523.

PD34-11 EFFECTS OF AGE AND MULTIPLE VAGINAL BIRTHS ON URINARY BLADDER, SPHINCTER STRUCTURE, FUNCTION AND PELVIC SUPPORT IN NONHUMAN PRIMATES

You have accessJournal of UrologyCME1 May 2022PD34-11 EFFECTS OF AGE AND MULTIPLE VAGINAL BIRTHS ON URINARY BLADDER, SPHINCTER STRUCTURE, FUNCTION AND PELVIC SUPPORT IN NONHUMAN PRIMATES J. Koudy Williams, Shannon Lankford, and Gopal Badlani J. Koudy WilliamsJ. Koudy Williams More articles by this author , Shannon LankfordShannon Lankford More articles by this author , and Gopal BadlaniGopal Badlani More articles by this author View All Author Informationhttps://doi.org/10.1097/JU.0000000000002585.11AboutPDF ToolsAdd to favoritesDownload CitationsTrack CitationsPermissionsReprints ShareFacebookLinked InTwitterEmail Abstract INTRODUCTION AND OBJECTIVE: Both aging and childbirth are associated with lower urinary tract dysfunction. However, the relative contribution of urinary bladder, urinary sphincter dysfunction and pelvic support remains unclear. This study uses female nonhuman primates (which have a 28 day menstrual cycle, an upright sitting posture and pelvic bladder and urinary sphincter) to address this issue. METHODS: Eight older (17-19 years of age, who have had an average of 7 live vaginal births) cynomolgus monkeys were compared to 6 younger (5 years of age, nulliparous) monkeys. Sedated abdominal leak point pressures (ALPP) were performed as well as urodynamic measures of sphincter maximal pressures (MUP) at rest and during pudendal nerve stimulation. Urinary sphincters, bladders and pelvic support muscles (levator ani and coccygeus) were examined for collagen content Masson’s trichrome, and picosirius red staining) and collagen fiber characteristics using CT-FIRE analysis. RESULTS: Aging and multiple vaginal births did not affect resting MUP measures, but did reduce the increase in MUP during pudendal nerve stimulation seen in the younger nulliparous monkeys (p<0.05) (Table 1). Age and multiple births did not affect total sphincter or bladder collagen content (Table 1, p>0.05), but did increase collagen content and reduce muscle content in the pelvic support muscles (p<0.05) (Table 1). ALPP was significantly lower in the older multiparous group than the young nulliparous group Table 1, p< 0.05). CONCLUSIONS: Results in this highly translatable animal model indicate that Lower urinary tract dysfunction associated with age and multiple births may be more a result of reduced sphincter response to neuronal stimulation and reduced pelvic support rather than intrinsic urinary sphincter or bladder structural and functional pathology. Source of Funding: National Institutes of Health, NIDDK © 2022 by American Urological Association Education and Research, Inc.FiguresReferencesRelatedDetails Volume 207Issue Supplement 5May 2022Page: e564 Advertisement Copyright & Permissions© 2022 by American Urological Association Education and Research, Inc.MetricsAuthor Information J. Koudy Williams More articles by this author Shannon Lankford More articles by this author Gopal Badlani More articles by this author Expand All Advertisement PDF DownloadLoading ...

Sacral neuromodulation of bladder underactivity induced by prolonged pudendal afferent firing in cats.

This study examined the effect of sacral neuromodulation on persistent bladder underactivity induced by prolonged pudendal nerve stimulation (PudNS). In 10 α-chloralose-anesthetized cats, repetitive application of 30-min PudNS induced bladder underactivity evident as an increase in bladder capacity during a cystometrogram (CMG). S1 or S2 dorsal root stimulation (15 or 30 Hz) at 1 or 1.5 times threshold intensity (T) for inducing reflex hindlimb movement (S1) or anal sphincter twitch (S2) was applied during a CMG to determine if the stimulation can reverse the bladder underactivity. Persistent (>3 h) bladder underactivity consisting of a significant increase in bladder capacity to 163.1 ± 11.3% of control was induced after repetitive (1-10 times) application of 30-min PudNS. S2 but not S1 dorsal root stimulation at 15 Hz and 1 T intensity reversed the PudNS-induced bladder underactivity by significantly reducing the large bladder capacity to 124.3 ± 12.9% of control. Other stimulation parameters were not effective. After the induction of persistent underactivity, recordings of reflex bladder activity under isovolumetric conditions revealed that S2 dorsal root stimulation consistently induced the largest bladder contraction at 15 Hz and 1 T when compared with other frequencies (5-40 Hz) or intensities (0.25-1.5 T). This study provides basic science evidence consistent with the hypothesis that abnormal pudendal afferent activity contributes to the bladder underactivity in Fowler's syndrome and that sacral neuromodulation treats this disorder by reversing the bladder inhibition induced by pudendal nerve afferent activity.

EDITORIAL COMMENT

This manuscript describes the very short-term effects of electrical pudendal nerve stimulation (EPNS) versus pelvic floor muscle training (PFMT) plus transanal electrical stimulation (TES) in Chinese men with urinary incontinence after radical prostatectomy. EPNS has been suggested for use in the management of stress urinary incontinence, urge urinary incontinence, urgency-frequency syndrome, and neurogenic lower urinary tract symptoms. In this parallel designed randomized controlled trial at a research institute and a university hospital, Chinese men with post-prostatectomy urinary incontinence were assigned to EPNS (64 patients) or PFMT plus TES (32 patients) and treated 3 times a week for 8 weeks.

AUTHOR REPLY

The purpose of this study was to develop and evaluate a short-term (8-week) treatment (Electrical pudendal nerve stimulation versus pelvic floor muscle training plus transanal electrical stimulation on post prostactomy urinary incontinence).Short-term treatment options will hopefully overcome the obstacle of poor compliance by patients with pelvic floor muscle training (PFMT) plus transanal electrical stimulation (TES). In our clinical practice, many patients drop out of treatment after 8 weeks.One of the probable reasons for dropout from PFMT plus TES is that the therapeutic effect often reaches a plateau after 8-weeks (24 sessions).

Superficial peroneal neuromodulation of nonobstructive urinary retention induced by prolonged pudendal afferent activity in cats.

The purpose of this study is to determine whether superficial peroneal nerve stimulation (SPNS) can improve nonobstructive urinary retention (NOUR) induced by prolonged pudendal nerve stimulation (PNS). In this exploratory acute study using eight cats under anesthesia, PNS and SPNS were applied by nerve cuff electrodes. Skin surface electrodes were also used for SPNS. A double lumen catheter was inserted via the bladder dome for bladder infusion and pressure measurement and to allow voiding without a physical urethral outlet obstruction. The voided and postvoid residual (PVR) volumes were also recorded. NOUR induced by repetitive (4-13 times) application of 30-min PNS significantly (P < 0.05) reduced voiding efficiency by 49.5 ± 16.8% of control (78.3 ± 7.9%), with a large PVR volume at 208.2 ± 82.6% of control bladder capacity. SPNS (1 Hz, 0.2 ms) at 1.5-2 times threshold intensity (T) for inducing posterior thigh muscle contractions was applied either continuously (SPNSc) or intermittently (SPNSi) during cystometrograms to improve the PNS-induced NOUR. SPNSc and SPNSi applied by nerve cuff electrodes significantly (P < 0.05) increased voiding efficiency to 74.5 ± 18.9% and 67.0 ± 15.3%, respectively, and reduced PVR volume to 54.5 ± 39.0% and 88.3 ± 56.0%, respectively. SPNSc and SPNSi applied noninvasively by skin surface electrodes also improved NOUR similar to the stimulation applied by a cuff electrode. This study indicates that abnormal pudendal afferent activity could be a pathophysiological cause for the NOUR occurring in Fowler's syndrome and a noninvasive superficial peroneal neuromodulation therapy might be developed to treat NOUR in patients with Fowler's syndrome.