The effects of neuromodulation in a novel obese-prone rat model of detrusor underactivity

Obesity is a global epidemic associated with an increased risk for lower urinary tract dysfunction. Inefficient voiding and urinary retention may arise in late-stage obesity when the expulsive force of the detrusor smooth muscle cannot overcome outlet resistance. Detrusor underactivity (DUA) and impaired contractility may contribute to the pathogenesis of nonobstructive urinary retention. We used cystometry and electrical stimulation of peripheral nerves (pudendal and pelvic nerves) to characterize and improve bladder function in urethane-anesthetized obese-prone (OP) and obese-resistant (OR) rats following diet-induced obesity (DIO). OP rats exhibited urinary retention and impaired detrusor contractility following DIO, reflected as increased volume threshold, decreased peak micturition pressure, and decreased voiding efficiency (VE) compared with OR rats. Electrical stimulation of the sensory branch of the pudendal nerve did not increase VE, whereas patterned bursting stimulation of the motor branch of the pudendal nerve increased VE twofold in OP rats. OP rats required increased amplitude of electrical stimulation of the pelvic nerve to elicit bladder contractions, and maximum evoked bladder contraction amplitudes were decreased relative to OR rats. Collectively, these studies characterize a novel animal model of DUA that can be used to determine pathophysiology and suggest that neuromodulation is a potential management option for DUA.

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Neuromodulation of the Pudendal Nerve Assisted by 3D Printed: A New Method of Neuromodulation for Lower Urinary Tract Dysfunction

Frontiers in Neuroscience ◽

10.3389/fnins.2021.619672 ◽

2021 ◽

Vol 15 ◽

Author(s):

Yinjun Gu ◽

Tingting Lv ◽

Chen Jiang ◽

Jianwei Lv

Keyword(s):

Electrical Stimulation ◽

Pelvic Floor ◽

Pudendal Nerve ◽

Operation Time ◽

Perineal Pain ◽

Lower Urinary Tract Dysfunction ◽

Implanted Electrodes ◽

Neural Modulation ◽

3D Printed ◽

Stimulation Of

Electrical stimulation of peripheral nerves by implanted electrodes is an effective treatment for certain pelvic floor diseases. As well as intravesical electrical stimulation, this predominantly includes stimulation of the sacral nerve, tibial nerve, and pudendal nerve. The pudendal nerve is one of the main nerves that stimulate pelvic floor muscles, external urethral meatus, and the anal sphincter and pelvic organs, and it may have effects on frequent urination, urgency, dysuria, and perineal pain. It is difficult to locate because of its anatomical course, however, leading to difficulties fixing the electrode, which increases the difficulty of pudendal nerve electrical stimulation in clinical practice. In the current study 3D printed navigation was used to solve these problems. Combined with autopsy data and patient pelvic and nerve data, a personalized design was generated. Neural modulation of the pudendal nerve was achieved by implanting the lead with the guidance of 3D printed navigation. 3D printed navigation can maximize the phase II conversion rate, reduce the difficulty of surgery, shorten the operation time, reduce damage to additional organs and blood vessels, and increase the accuracy of electrode implantation, and it can be performed while the patient is awake. It is an accurate, reversible, efficient, and minimally invasive surgery.

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Effects of acute selective pudendal nerve electrical stimulation after simulated childbirth injury

AJP Renal Physiology ◽

10.1152/ajprenal.00235.2012 ◽

2013 ◽

Vol 304 (3) ◽

pp. F239-F247 ◽

Cited By ~ 12

Author(s):

Hai-Hong Jiang ◽

Bradley C. Gill ◽

Charuspong Dissaranan ◽

Massarat Zutshi ◽

Brian M. Balog ◽

...

Keyword(s):

Electrical Stimulation ◽

Pudendal Nerve ◽

Contractile Function ◽

Female Rats ◽

Bdnf Expression ◽

Nerve Crush ◽

Motor Branch ◽

Onuf's Nucleus ◽

Onuf’S Nucleus ◽

Stimulation Of

During childbirth, a combinatorial injury occurs and can result in stress urinary incontinence (SUI). Simulated childbirth injury, consisting of vaginal distension (VD) and pudendal nerve crush (PNC), results in slowed recovery of continence, as well as decreased expression of brain-derived neurotrophic factor (BDNF), a regenerative cytokine. Electrical stimulation has been shown to upregulate BDNF in motor neurons and facilitate axon regrowth through the increase of βII-tubulin expression after injury. In this study, female rats underwent selective pudendal nerve motor branch (PNMB) stimulation after simulated childbirth injury or sham injury to determine whether such stimulation affects bladder and anal function after injury and whether the stimulation increases BDNF expression in Onuf's nucleus after injury. Rats received 4 h of VD followed by bilateral PNC and 1 h of subthreshold electrical stimulation of the left PNMB and sham stimulation of the right PNMB. Rats underwent filling cystometry and anal pressure recording before, during, and after the stimulation. Bladder and anal contractile function were partially disrupted after injury. PNMB stimulation temporarily inhibited bladder contraction after injury. Two days and 1 wk after injury, BDNF expression in Onuf's nucleus of the stimulated side was significantly increased compared with the sham-stimulated side, whereas βII-tubulin expression in Onuf's nucleus of the stimulated side was significantly increased only 1 wk after injury. Acute electrical stimulation of the pudendal nerve proximal to the crush site upregulates BDNF and βII-tubulin in Onuf's nucleus after simulated childbirth injury, which could be a potential preventive option for SUI after childbirth injury.

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Intraoperative monitoring for tethered cord surgery: an update

Neurosurgical FOCUS ◽

10.3171/foc.2004.16.2.1 ◽

2004 ◽

Vol 16 (2) ◽

pp. E8 ◽

Cited By ~ 71

Author(s):

Karl F. Kothbauer ◽

Klaus Novak

Keyword(s):

Electrical Stimulation ◽

Anal Sphincter ◽

External Anal Sphincter ◽

Continuous Monitoring ◽

Pudendal Nerve ◽

Tethered Cord ◽

Sensory Pathways ◽

Functional Integrity ◽

Muscle Responses ◽

Stimulation Of

Object Intraoperative neurophysiological recording techniques have found increasing use in neurosurgical practice. The development of new recording techniques feasible while the patient receives a general anesthetic have improved their practical use in a similar way to the use of digital recording, documentation, and video technology. This review intends to provide an update on the techniques used and their validity. Methods Two principal methods are used for intraoperative neurophysiological testing during tethered cord release. Mapping identifies functional neural structures, namely nerve roots, and monitoring provides continuous information on the functional integrity of motor and sensory pathways as well as reflex circuitry. Mapping is performed mostly by using direct electrical stimulation of a structure within the surgical field and recording at a distant site, usually a muscle. Sensory mapping can also be performed with peripheral stimulation and recording within the surgical site. Monitoring of the motor system is achieved with motor evoked potentials. These are evoked by transcranial electrical stimulation and recorded from limb muscles and the external anal sphincter. The presence or absence of muscle responses are the parameters monitored. Sensory potentials evoked by tibial or pudendal nerve stimulation and recorded from the dorsal columns via an epidurally inserted electrode and/or from the scalp as cortical responses are used to access the integrity of sensory pathways. Amplitudes and latencies of these responses are then interpreted. The bulbocavernosus reflex, with stimulation of the pudendal nerve and recording of muscle responses in the external anal sphincter, is used for continuous monitoring of the reflex circuitry. Presence or absence of this response is the pertinent parameter that is monitored. Conclusions Intraoperative neurophysiology provides a wide and reliable set of techniques for intraoperative identification of neural structures and continuous monitoring of their functional integrity.

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Effect of distal esophageal irritation on the changes of cystometry parameters to esophagus and colon distentions in rats

Canadian Journal of Physiology and Pharmacology ◽

10.1139/cjpp-2019-0122 ◽

2019 ◽

Vol 97 (8) ◽

pp. 766-772

Author(s):

Ezidin G. Kaddumi

Keyword(s):

Electrical Stimulation ◽

Urinary Bladder ◽

Vagus Nerve ◽

Storage Time ◽

Distal Colon ◽

Bladder Function ◽

Maximum Pressure ◽

Pressure Amplitude ◽

Chemical Irritation ◽

Stimulation Of

The coexistence of different visceral pathologies in patients suffering from irritable bowel syndrome, interstitial cystitis, and other pathologies, necessitates the study of these pathologies under complicated conditions. In the present study, cystometry recordings were used to investigate the effect of distal esophageal chemical irritation on the urinary bladder interaction with distal colon distention, distal esophageal distention, and electrical stimulation of abdominal branches of vagus nerve. Distal esophageal chemical irritation significantly decreased the intercontraction time via decreasing the voiding time. Also, distal esophageal chemical irritation significantly decreased the pressure amplitude by decreasing the maximum pressure. Following distal esophageal chemical irritation, distal esophageal distention was able to significantly decrease the intercontraction time by decreasing the storage time. However, 3 mL distal colon distention significantly increased the intercontraction time by increasing the storage time. On the other hand, following distal esophageal chemical irritation, electrical stimulation of abdominal branches of vagus nerve did not have any significant effect on intercontraction time. However, electrical stimulation of abdominal branches of vagus nerve significantly increased the pressure amplitude by increasing the maximum pressure. The results of this study demonstrate that urinary bladder function and interaction of bladder with other viscera can be affected by chemical irritation of distal esophagus.

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Epidural Electrical Stimulation on Neurogenic Bladder

Urologia Journal ◽

10.1177/039156039306000116 ◽

1993 ◽

Vol 60 (1) ◽

pp. 87-89 ◽

Cited By ~ 1

Author(s):

C. Simeone ◽

E. Frego ◽

T. Zanotelli ◽

R. Capra ◽

A. Lenzi ◽

...

Keyword(s):

Spinal Cord ◽

Electrical Stimulation ◽

Beneficial Effect ◽

Bladder Dysfunction ◽

Bladder Capacity ◽

Bladder Function ◽

Complete Relief ◽

Detrusor Sphincter Dyssynergia ◽

Thoracic Level ◽

Stimulation Of

In 1967 Shealy first used electrical stimulation of the spinal cord to treat spasticity and pain. This therapy proved to be effective for bladder dysfunction too. The effect of electrical stimulation of the spinal cord at thoracic level has been evaluated in 18 neurogenic patients suffering from hyperreflexia with detrusor-sphincter dyssynergia. Bladder function improved significantly in 13 (73%). Partial or complete relief of bladder hyperreflexia, marked increased of bladder capacity and reduction of residual urine were recorded. The beneficial effect of stimulation indicates that it is a safe and effective alternative treatment for the neuropathic bladder and careful trials with further investigations should be carried out.

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