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Warrier S, Rutter EM, Flores KB. Multitask neural networks for predicting bladder pressure with time series data. Biomed Signal Process Control 2022; 72:103298. [DOI: 10.1016/j.bspc.2021.103298] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
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Balog BM, Deng K, Labhasetwar V, Jones KJ, Damaser MS. Electrical stimulation for neuroregeneration in urology: a new therapeutic paradigm. Curr Opin Urol 2019; 29:458-65. [PMID: 30985344 DOI: 10.1097/MOU.0000000000000632] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/07/2023]
Abstract
PURPOSE OF REVIEW The present review highlights regenerative electrical stimulation (RES) as potential future treatment options for patients with nerve injuries leading to urological dysfunction, such as urinary incontinence, voiding dysfunction or erectile dysfunction. Additionally, it will highlight the mechanism of nerve injury and regeneration as well as similarities and differences between RES and current electrical stimulation treatments in urology, functional electrical stimulation (FES) and neuromodulation. RECENT FINDINGS It has been demonstrated that RES upregulates brain-derived neurotrophic factor (BDNF) and its receptor to facilitate neuroregeneration, facilitating accurate reinnervation of muscles by motoneurons. Further, RES upregulates growth factors in glial cells. Within the past 2 years, RES of the pudendal nerve upregulated BDNF in Onuf's nucleus, the cell bodies of motoneurons that course through the pudendal nerve and accelerated functional recovery in an animal model of stress urinary incontinence. Additionally, electrical stimulation of the vaginal tissue in an animal model of stress urinary incontinence accelerated functional recovery. SUMMARY RES has great potential but future research is needed to expand the potential beneficial effects of RES in the field of urology.
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Kisby CK, Gonzalez EJ, Visco AG, Amundsen CL, Grill WM. Randomized Controlled Trial to Assess the Impact of Intraurethral Lidocaine on Urodynamic Voiding Parameters. Female Pelvic Med Reconstr Surg 2019; 25:265-70. [PMID: 29300256 DOI: 10.1097/SPV.0000000000000544] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/23/2023]
Abstract
OBJECTIVES The aim of the study was to determine whether intraurethral anesthesia decreases voiding efficiency (VE; voided volume/(voided volume + residual volume)) and impacts other urodynamic parameters in healthy female volunteers during urodynamic studies. METHODS This was a randomized double-blind placebo-controlled study of asymptomatic women aged 18 to 60 years. Subjects completed a visual analog scale and baseline questionnaires to assess pain and lower urinary tract symptoms, respectively. They performed an uninstrumented baseline uroflow, followed by physiologic filling to 250 mL or greater. Subjects were randomized to receive 5 mL of intraurethral aqueous gel or 2% lidocaine gel and then underwent a second uninstrumented uroflow. They then completed complex cystometry, urethral pressure profilometry, and pressure-flow studies. RESULTS Twenty-three randomized subjects (12 placebo, 11 lidocaine) were included. Baseline uroflow VE was similar between the placebo and lidocaine groups. After study drug administration, VE was not different between groups (89.3 [85.9-93.9] vs 89.5 [82.5-91.7], P = 0.74). There were also no differences between groups in visual analog scale scores, sensation during cystometry, maximum urethral closure pressure, or micturition parameters (maximum detrusor pressure and detrusor pressure at maximum flow). The placebo group had a lower percentage of interrupted flow pattern (0% vs 36%, P = 0.02) and a lower rate of increased electromyographic activity during micturition (25% vs 73%, P = 0.02). CONCLUSIONS In this pilot study of 23 asymptomatic women, intraurethral administration of lidocaine did not decrease VE compared with placebo. The lidocaine group had a greater percentage of interrupted flow patterns and increased electromyographic activity during micturition.
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Keller EE, Patras I, Hutu I, Roider K, Sievert KD, Aigner L, Janetschek G, Lusuardi L, Zimmermann R, Bauer S. Early sacral neuromodulation ameliorates urinary bladder function and structure in complete spinal cord injury minipigs. Neurourol Urodyn 2019; 39:586-593. [PMID: 31868966 PMCID: PMC7027870 DOI: 10.1002/nau.24257] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/11/2019] [Accepted: 12/03/2019] [Indexed: 12/12/2022]
Abstract
Aims To determine the effects of early sacral neuromodulation (SNM) and pudendal neuromodulation (PNM) on lower urinary tract (LUT) function, minipigs with complete spinal cord injury (cSCI) were analyzed. SNM and PNM have been proposed as therapeutic approaches to improve bladder function, for example after cSCI. However, further evidence on efficacy is required before these methods can become clinical practice. Methods Eleven adults, female Göttingen minipigs with cSCI at vertebral level T11‐T12 were included: SNM (n = 4), PNM (n = 4), and SCI control (SCIC: n = 3). Tissue from six healthy minipigs was used for structural comparisons. Stimulation was started 1 week after cSCI. Awake urodynamics was performed on a weekly basis. After 16 weeks follow‐up, samples from the urinary bladder were taken for analyses. Results SNM improved bladder function with better capacities and lower detrusor pressures at voiding and avoided the emergence of detrusor sphincter dyssynergia (DSD). PNM and untreated SCI minipigs had less favorable outcomes with either DSD or constant urinary retention. Structural results revealed SCI‐typical fibrotic alterations in all cSCI minipigs. However, SNM showed a better‐balanced distribution of smooth muscle to connective tissue with a trend towards the reduced progression of bladder wall scarring. Conclusion Early SNM led to an avoidance of the emergence of DSD showing a more physiological bladder function during a 4 month follow‐up period after cSCI. This study might pave the way for the clinical continuation of early SNM for the treatment of neurogenic LUT dysfunction after SCI.
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Affiliation(s)
- Elena E Keller
- Department of Urology and Andrology, University Clinics Salzburg, Salzburg, Austria.,Spinal Cord Injury and Tissue Regeneration Center Salzburg, Paracelsus Medical University, Salzburg, Austria.,Institute of Molecular Regenerative Medicine, Paracelsus Medical University, Salzburg, Austria
| | - Irina Patras
- Banat University of Agricultural Science and Veterinary Medicine, Timișoara, Romania
| | - Ioan Hutu
- Banat University of Agricultural Science and Veterinary Medicine, Timișoara, Romania
| | - Karin Roider
- Department of Urology and Andrology, University Clinics Salzburg, Salzburg, Austria.,Spinal Cord Injury and Tissue Regeneration Center Salzburg, Paracelsus Medical University, Salzburg, Austria.,Institute of Molecular Regenerative Medicine, Paracelsus Medical University, Salzburg, Austria
| | - Karl-Dietrich Sievert
- Klinik für Urologie, Klinikum Lippe, Detmold, Germany.,Department of Urology, Comprehensive Cancer Center, Medical University Vienna, Vienna, Austria
| | - Ludwig Aigner
- Institute of Molecular Regenerative Medicine, Paracelsus Medical University, Salzburg, Austria.,Austrian Cluster of Tissue Regeneration, Vienna, Austria
| | - Günter Janetschek
- Spinal Cord Injury and Tissue Regeneration Center Salzburg, Paracelsus Medical University, Salzburg, Austria
| | - Lukas Lusuardi
- Department of Urology and Andrology, University Clinics Salzburg, Salzburg, Austria
| | | | - Sophina Bauer
- Department of Urology and Andrology, University Clinics Salzburg, Salzburg, Austria
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Niu T, Bennett CJ, Keller TL, Leiter JC, Lu DC. A Proof-of-Concept Study of Transcutaneous Magnetic Spinal Cord Stimulation for Neurogenic Bladder. Sci Rep 2018; 8:12549. [PMID: 30135433 DOI: 10.1038/s41598-018-30232-z] [Citation(s) in RCA: 20] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/19/2018] [Accepted: 07/25/2018] [Indexed: 01/01/2023] Open
Abstract
Patients with chronic spinal cord injury (SCI) cannot urinate at will and must empty the bladder by self-catheterization. We tested the hypothesis that non-invasive, transcutaneous magnetic spinal cord stimulation (TMSCS) would improve bladder function in individuals with SCI. Five individuals with American Spinal Injury Association Impairment Scale A/B, chronic SCI and detrusor sphincter dyssynergia enrolled in this prospective, interventional study. After a two-week assessment to determine effective stimulation characteristics, each patient received sixteen weekly TMSCS treatments and then received “sham” weekly stimulation for six weeks while bladder function was monitored. Bladder function improved in all five subjects, but only during and after repeated weekly sessions of 1 Hz TMSCS. All subjects achieved volitional urination. The volume of urine produced voluntarily increased from 0 cc/day to 1120 cc/day (p = 0.03); self-catheterization frequency decreased from 6.6/day to 2.4/day (p = 0.04); the capacity of the bladder increased from 244 ml to 404 ml (p = 0.02); and the average quality of life ranking increased significantly (p = 0.007). Volitional bladder function was re-enabled in five individuals with SCI following intermittent, non-invasive TMSCS. We conclude that neuromodulation of spinal micturition circuitry by TMSCS may be used to ameliorate bladder function.
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Rutter EM, Langdale CL, Hokanson JA, Hamilton F, Tran H, Grill WM, Flores KB. Detection of Bladder Contractions From the Activity of the External Urethral Sphincter in Rats Using Sparse Regression. IEEE Trans Neural Syst Rehabil Eng 2018; 26:1636-1644. [PMID: 30004881 DOI: 10.1109/tnsre.2018.2854675] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/15/2022]
Abstract
Bladder overactivity and incontinence and dysfunction can be mitigated by electrical stimulation of the pudendal nerve applied at the onset of a bladder contraction. Thus, it is important to predict accurately both bladder pressure and the onset of bladder contractions. We propose a novel method for prediction of bladder pressure using a time-dependent spectrogram representation of external urethral sphincter electromyographic (EUS EMG) activity and a least absolute shrinkage and selection operator regression model. There was a statistically significant improvement in prediction of bladder pressure compared with methods based on the firing rate of EUS EMG activity. This approach enabled prediction of the onset of bladder contractions with 91% specificity and 96% sensitivity and may be suitable for closed-loop control of bladder continence.
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Langdale CL, Hokanson JA, Sridhar A, Grill WM. Stimulation of the pelvic nerve increases bladder capacity in the prostaglandin E 2 rat model of overactive bladder. Am J Physiol Renal Physiol 2017; 313:F657-F665. [PMID: 28615244 DOI: 10.1152/ajprenal.00116.2017] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/09/2017] [Revised: 05/25/2017] [Accepted: 06/06/2017] [Indexed: 01/23/2023] Open
Abstract
Overactive bladder (OAB) syndrome is a highly prevalent condition that may lead to medical complications and decreased quality of life. Emerging therapies focusing on selective electrical stimulation of peripheral nerves associated with lower urinary tract function may provide improved efficacy and reduced side effects compared with sacral neuromodulation for the treatment of OAB symptoms. Prior studies investigating the effects of pelvic nerve (PelN) stimulation on lower urinary tract function were focused on promoting bladder contractions, and it is unclear whether selective stimulation of the PelN would be beneficial for the treatment of OAB. Therefore our motivation was to test the hypothesis that PelN stimulation would increase bladder capacity in the prostaglandin E2 (PGE2) rat model of OAB. Cystometry experiments were conducted in 17 urethane-anesthetized female Sprague-Dawley rats. The effects of intravesical PGE2 vs. vehicle and PelN stimulation after intravesical PGE2 on cystometric parameters were quantified. Intravesical infusion of PGE2 resulted in decreased bladder capacity and increased voiding efficiency without a change in bladder contraction area under the curve, maximum contraction pressure, or contraction duration. Bladder capacity was also significantly decreased compared with vehicle (1% ethanol in saline) confirming that the change in bladder capacity was mediated by PGE2 PelN stimulation reversed the PGE2-induced change in bladder capacity and increased the external urethral sphincter electromyogram activity at a specific stimulation condition (amplitude of 1.0 times threshold at 10 Hz). These results confirm that the urodynamic changes reported in conscious rats are also observed under urethane anesthesia and that PelN stimulation is a novel and promising approach for the treatment of the symptoms of OAB.
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Affiliation(s)
| | - James A Hokanson
- Department of Biomedical Engineering, Duke University, Durham, North Carolina
| | - Arun Sridhar
- Bioelectronics Research and Development, GlaxoSmithKline, Stevenage, United Kingdom
| | - Warren M Grill
- Department of Biomedical Engineering, Duke University, Durham, North Carolina; .,Department of Electrical and Computer Engineering, Duke University, Durham, North Carolina.,Department of Neurobiology, Duke University, Durham, North Carolina.,Department of Neurosurgery, Duke University, Durham, North Carolina; and
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Pettigrew RI, Heetderks WJ, Kelley CA, Peng GC, Member IEEE, Krosnick SH, Jakeman LB, Egan KD, Marge M. Epidural Spinal Stimulation to Improve Bladder, Bowel, and Sexual Function in Individuals With Spinal Cord Injuries: A Framework for Clinical Research. IEEE Trans Biomed Eng 2017; 64:253-262. [PMID: 28113186 PMCID: PMC5513553 DOI: 10.1109/tbme.2016.2637301] [Citation(s) in RCA: 33] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/16/2022]
Abstract
While some recent studies that apply epidural spinal cord stimulation (SCS) have demonstrated a breakthrough in improvement of the health and quality of the life of persons with spinal cord injury (SCI), the numbers of people who have received SCS are small. This is in sharp contrast to the thousands of persons worldwide living with SCI who have no practical recourse or hope of recovery of lost functions. Thus, the vision is to understand the full potential of this new intervention and to determine if it is safe and effective in a larger cohort, and if it is scalable so that it can be made available to all those who might benefit. To achieve this vision, the National Institute of Biomedical Imaging and Bioengineering called for and organized a consortium of multiple stakeholder groups: foundations addressing paralysis, federal and public agencies, industrial partners, academicians, and researchers, all interested in the same goal. Based on input from consortium participants, we have reasoned that a first step is to define a scalable SCS approach that is effective in restoring lost autonomic physiology, specifically bladder, bowel, and sexual function. These functions are most critical for improving the quality of life of persons living with SCI. This report outlines a framework for conducting the research needed to define such an effective SCS procedure that might seek Food and Drug Administration approval and be implemented at the population level.
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Affiliation(s)
| | - William J. Heetderks
- Formerly with the National Institute of Biomedical Imaging and Bioengineering and is now employed by the Food and Drug Administration
| | - Christine A. Kelley
- Employees of the National Institute of Biomedical Imaging and Bioengineering
| | - Grace C.Y. Peng
- Employees of the National Institute of Biomedical Imaging and Bioengineering
| | - IEEE Member
- Employees of the National Institute of Biomedical Imaging and Bioengineering
| | - Steven H. Krosnick
- Employees of the National Institute of Biomedical Imaging and Bioengineering
| | - Lyn B. Jakeman
- Employee of the National Institute of Neurological Diseases and Stroke
| | - Katharine D. Egan
- Employees of the National Institute of Biomedical Imaging and Bioengineering
| | - Michael Marge
- Employees of the National Institute of Biomedical Imaging and Bioengineering
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Popovic MR, Zivanovic V, Valiante TA. Restoration of Upper Limb Function in an Individual with Cervical Spondylotic Myelopathy using Functional Electrical Stimulation Therapy: A Case Study. Front Neurol 2016; 7:81. [PMID: 27375547 PMCID: PMC4901066 DOI: 10.3389/fneur.2016.00081] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/16/2016] [Accepted: 05/05/2016] [Indexed: 11/13/2022] Open
Abstract
Non-traumatic spinal cord pathology is responsible for 25–52% of all spinal cord lesions. Studies have revealed that spinal stenosis accounts for 16–21% of spinal cord injury (SCI) admissions. Impaired grips as well as slow unskilled hand and finger movements are the most common complaints in patients with spinal cord disorders, such as myelopathy secondary to cervical spondylosis. In the past, our team carried out couple of successful clinical trials, including two randomized control trials, showing that functional electrical stimulation therapy (FEST) can restore voluntary reaching and/or grasping function, in people with stroke and traumatic SCI. Motivated by this success, we decided to examine changes in the upper limb function following FEST in a patient who suffered loss of hand function due to myelopathy secondary to cervical spondylosis. The participant was a 61-year-old male who had C3–C7 posterior laminectomy and instrumented fusion for cervical myelopathy. The participant presented with progressive right hand weakness that resulted in his inability to voluntarily open and close the hand and to manipulate objects unilaterally with his right hand. The participant was enrolled in the study ~22 months following initial surgical intervention. Participant was assessed using Toronto Rehabilitation Institute’s Hand Function Test (TRI-HFT), Action Research Arm Test (ARAT), Functional Independence Measure (FIM), and Spinal Cord Independence Measure (SCIM). The pre–post differences in scores on all measures clearly demonstrated improvement in voluntary hand function following 15 1-h FEST sessions. The changes observed were meaningful and have resulted in substantial improvement in performance of activities of daily living. These results provide preliminary evidence that FEST has a potential to improve upper limb function in patients with non-traumatic SCI, such as myelopathy secondary to cervical spondylosis.
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Affiliation(s)
- Milos R Popovic
- Institute of Biomaterials and Biomedical Engineering, University of Toronto, Toronto, ON, Canada; Rehabilitation Engineering Laboratory, Lyndhurst Centre, Toronto Rehabilitation Institute - University Health Network, Toronto, ON, Canada
| | - Vera Zivanovic
- Rehabilitation Engineering Laboratory, Lyndhurst Centre, Toronto Rehabilitation Institute - University Health Network , Toronto, ON , Canada
| | - Taufik A Valiante
- Institute of Biomaterials and Biomedical Engineering, University of Toronto, Toronto, ON, Canada; Krembil Research Institute - University Health Network, Toronto, ON, Canada
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Langdale CL, Grill WM. Phasic activation of the external urethral sphincter increases voiding efficiency in the rat and the cat. Exp Neurol 2016; 285:173-181. [PMID: 27235934 DOI: 10.1016/j.expneurol.2016.05.030] [Citation(s) in RCA: 24] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/30/2015] [Revised: 04/29/2016] [Accepted: 05/23/2016] [Indexed: 10/21/2022]
Abstract
OBJECTIVE Electrical stimulation of the pudendal nerve (PN) is a potential therapy for bladder dysfunction, but voiding efficiency (VE) produced by PN stimulation appears limited to 60-70%. We conducted experiments in rats and cats to investigate the hypothesis that introduction of artificial phasic bursting activity of the external urethral sphincter (EUS) would enhance VE under conditions where such activity was absent. MATERIALS AND METHODS Cystometry experiments were conducted in 17 urethane anesthetized female Sprague-Dawley rats and 4 α-chloralose anesthetized male cats. The effects of phasic stimulation of the pudendal motor branch on VE were quantified in intact conditions, following bilateral transection of the motor branch of the PN, and following subsequent bilateral transection of the sensory branch of the PN. RESULTS Artificial phasic bursting activity in the EUS generated by electrical stimulation of the motor branch of the PN increased VE in both rats and cats. Subsequent transection of the sensory branch of the PN abolished the increased VE elicited by phasic stimulation in both rats and cats. CONCLUSIONS Artificial phasic EUS bursting restored efficient voiding in rats. Introduction of artificial phasic bursting in cats, which normally exhibit EUS relaxation while voiding, was also effective in promoting efficient voiding. In both species phasic EUS activity increased voiding efficiency via activation of pudendal sensory pathways. These results provide further insight into the function of phasic EUS activity in efficient voiding and highlight a novel approach to increase VE generated by pudendal afferent nerve stimulation.
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Affiliation(s)
| | - Warren M Grill
- Department of Biomedical Engineering, Duke University, Durham, NC, USA; Department of Electrical and Computer Engineering, Duke University, Durham, NC, USA; Department of Neurobiology, Duke University, Durham, NC, USA; Department of Surgery, Duke University, Durham, NC, USA.
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Nagai MK, Marquez-Chin C, Popovic MR. Why Is Functional Electrical Stimulation Therapy Capable of Restoring Motor Function Following Severe Injury to the Central Nervous System? Transl Neurosci 2016. [DOI: 10.1007/978-1-4899-7654-3_25] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/22/2022] Open
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Eggermont M, Wyndaele JJ, Gillespie J, De Wachter S. Response Properties of Urethral Distension Evoked Unifiber Afferent Potentials in the Lower Urinary Tract. J Urol 2015; 194:1473-80. [PMID: 26055821 DOI: 10.1016/j.juro.2015.05.094] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 05/27/2015] [Indexed: 11/28/2022]
Abstract
PURPOSE It is well known that afferent input from the urethra can modulate bladder function. Nevertheless, little is known about the functional properties of urethral afferents. In the current study we investigated the effect of urethral distension on single fiber afferent activities of the lower urinary tract in the female rat. MATERIALS AND METHODS Female Sprague Dawley® rats were anesthetized. Single fiber afferent activities were recorded from the left L6 dorsal root and classified by conduction velocity. The response of pelvic and pudendal units on urethral distension (60 seconds) was measured. Two distension diameters were measured in the proximal and the distal urethra. RESULTS A total of 93 pelvic and 72 pudendal units were isolated in 15 rats. Of the units 20 (8 pelvic and 12 pudendal) were responsive to urethral distension. Three patterns of response could be distinguished, including a fast adapting and 2 groups of slow adapting afferents. The largest grade of distension resulted in the greatest response in both nerves. Five pelvic and 3 pudendal units responded exclusively to proximal distension, 2 pelvic and 5 pudendal units responded to distal distension, and 1 pelvic and 4 pudendal units responded to both types of distension. The responses were reproducible. No association was found between the type of nerve and the location of the response to distension. CONCLUSIONS This electrophysiological study demonstrates the presence of urethral distension evoked afferents in the pelvic and pudendal nerves, and describes their response to distension. Differences in sensory signaling in type and in location were demonstrated. The current technique can be used for further investigation of urethral afferents.
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Affiliation(s)
- Monica Eggermont
- Department of Urology, Antwerp University Hospital and Faculty of Medicine, University of Antwerp, Antwerp, Belgium; Uro-Physiology Research Group, Dental and Medical School, Newcastle University (JG), Newcastle upon Tyne, United Kingdom
| | - Jean-Jacques Wyndaele
- Department of Urology, Antwerp University Hospital and Faculty of Medicine, University of Antwerp, Antwerp, Belgium; Uro-Physiology Research Group, Dental and Medical School, Newcastle University (JG), Newcastle upon Tyne, United Kingdom
| | - James Gillespie
- Department of Urology, Antwerp University Hospital and Faculty of Medicine, University of Antwerp, Antwerp, Belgium; Uro-Physiology Research Group, Dental and Medical School, Newcastle University (JG), Newcastle upon Tyne, United Kingdom
| | - Stefan De Wachter
- Department of Urology, Antwerp University Hospital and Faculty of Medicine, University of Antwerp, Antwerp, Belgium; Uro-Physiology Research Group, Dental and Medical School, Newcastle University (JG), Newcastle upon Tyne, United Kingdom.
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de Groat WC, Tai C. Impact of Bioelectronic Medicine on the Neural Regulation of Pelvic Visceral Function. Bioelectron Med 2015; 2015:25-36. [PMID: 26491706 PMCID: PMC4610375] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Grants] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 06/05/2023] Open
Abstract
Neuromodulation elicited by electrical stimulation of peripheral or spinal nerves is a U.S. Food and Drug Administered (FDA)-approved therapy for treating disorders of the pelvic viscera, including urinary urgency, urgency-frequency, nonobstructive urinary retention and fecal incontinence. The technique is also being tested experimentally for its efficacy in treating interstitial cystitis, chronic constipation and pelvic pain. The goal of neuromodulation is to suppress abnormal visceral sensations and involuntary reflexes and restore voluntary control. Although detailed mechanisms underlying the effects of neuromodulation are still to be elucidated, it is generally believed that effects are due to stimulation of action potentials in somatic afferent nerves. Afferent nerves project to the lumbosacral spinal cord, where they release excitatory neurotransmitters that activate ascending pathways to the brain or spinal circuits that modulate visceral sensory and involuntary motor mechanisms. Studies in animals revealed that different types of neuromodulation (for example, stimulation of a sacral spinal root, pudendal nerve or posterior tibial nerve) act by releasing different inhibitory and excitatory neurotransmitters in the central nervous system. In addition, certain types of neuromodulation inhibit visceral smooth muscle by initiating reflex firing in peripheral autonomic nerves or excite striated sphincter muscles by initiating reflex firing in somatic efferent nerves. This report will provide a brief summary of (a) neural control of the lower urinary tract and distal bowel, (b) clinical use of neuromodulation in the treatment of bladder and bowel dysfunctions,
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Affiliation(s)
- William C de Groat
- Department of Pharmacology and Chemical Biology, University of Pittsburgh Medical School, Pittsburgh, Pennsylvania, United States of America
| | - Changfeng Tai
- Department of Pharmacology and Chemical Biology, University of Pittsburgh Medical School, Pittsburgh, Pennsylvania, United States of America
- Department of Urology, University of Pittsburgh Medical School, Pittsburgh, Pennsylvania, United States of America
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Abstract
This article summarizes anatomical, neurophysiological, pharmacological, and brain imaging studies in humans and animals that have provided insights into the neural circuitry and neurotransmitter mechanisms controlling the lower urinary tract. The 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. The neural control of micturition is organized as a hierarchical system in which spinal storage mechanisms are in turn regulated by circuitry in the rostral brain stem that initiates reflex voiding. Input from the forebrain triggers voluntary voiding by modulating the brain stem 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 in infants and young children until the age of 3 to 5 years, after which it is regulated voluntarily. Diseases or injuries of the nervous system in adults can cause the re-emergence of involuntary micturition, leading to urinary incontinence. Neuroplasticity underlying these developmental and pathological changes in voiding function is discussed.
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Affiliation(s)
- William C. de Groat
- Department of Pharmacology and Chemical Biology, University of Pittsburgh, School of Medicine Pittsburgh, Pennsylvania
| | - Derek Griffiths
- Department of Medicine (Geriatrics), University of Pittsburgh, School of Medicine Pittsburgh, Pennsylvania
| | - Naoki Yoshimura
- Department of Pharmacology and Chemical Biology, University of Pittsburgh, School of Medicine Pittsburgh, Pennsylvania
- Department of Urology, University of Pittsburgh, School of Medicine Pittsburgh, Pennsylvania
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Grahn PJ, Lee KH, Kasasbeh A, Mallory GW, Hachmann JT, Dube JR, Kimble CJ, Lobel DA, Bieber A, Jeong JH, Bennet KE, Lujan JL. Wireless control of intraspinal microstimulation in a rodent model of paralysis. J Neurosurg 2014; 123:232-242. [PMID: 25479124 DOI: 10.3171/2014.10.jns132370] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/28/2022]
Abstract
OBJECT Despite a promising outlook, existing intraspinal microstimulation (ISMS) techniques for restoring functional motor control after spinal cord injury are not yet suitable for use outside a controlled laboratory environment. Thus, successful application of ISMS therapy in humans will require the use of versatile chronic neurostimulation systems. The objective of this study was to establish proof of principle for wireless control of ISMS to evoke controlled motor function in a rodent model of complete spinal cord injury. METHODS The lumbar spinal cord in each of 17 fully anesthetized Sprague-Dawley rats was stimulated via ISMS electrodes to evoke hindlimb function. Nine subjects underwent complete surgical transection of the spinal cord at the T-4 level 7 days before stimulation. Targeting for both groups (spinalized and control) was performed under visual inspection via dorsal spinal cord landmarks such as the dorsal root entry zone and the dorsal median fissure. Teflon-insulated stimulating platinum-iridium microwire electrodes (50 μm in diameter, with a 30- to 60-μm exposed tip) were implanted within the ventral gray matter to an approximate depth of 1.8 mm. Electrode implantation was performed using a free-hand delivery technique (n = 12) or a Kopf spinal frame system (n = 5) to compare the efficacy of these 2 commonly used targeting techniques. Stimulation was controlled remotely using a wireless neurostimulation control system. Hindlimb movements evoked by stimulation were tracked via kinematic markers placed on the hips, knees, ankles, and paws. Postmortem fixation and staining of the spinal cord tissue were conducted to determine the final positions of the stimulating electrodes within the spinal cord tissue. RESULTS The results show that wireless ISMS was capable of evoking controlled and sustained activation of ankle, knee, and hip muscles in 90% of the spinalized rats (n = 9) and 100% of the healthy control rats (n = 8). No functional differences between movements evoked by either of the 2 targeting techniques were revealed. However, frame-based targeting required fewer electrode penetrations to evoke target movements. CONCLUSIONS Clinical restoration of functional movement via ISMS remains a distant goal. However, the technology presented herein represents the first step toward restoring functional independence for individuals with chronic spinal cord injury.
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Affiliation(s)
- Peter J Grahn
- Mayo Graduate School, Mayo Clinic, Rochester, Minnesota
| | - Kendall H Lee
- Department of Neurologic Surgery, Mayo Clinic, Rochester, Minnesota.,Department of Physiology and Biomedical Engineering, Mayo Clinic, Rochester, Minnesota
| | - Aimen Kasasbeh
- Department of Neurologic Surgery, Mayo Clinic, Rochester, Minnesota
| | - Grant W Mallory
- Department of Neurologic Surgery, Mayo Clinic, Rochester, Minnesota
| | - Jan T Hachmann
- Mayo Graduate School, Mayo Clinic, Rochester, Minnesota.,Department of Neurologic Surgery, Mayo Clinic, Rochester, Minnesota
| | - John R Dube
- Department of Neurologic Surgery, Mayo Clinic, Rochester, Minnesota
| | | | - Darlene A Lobel
- Department of Neurologic Surgery, Mayo Clinic, Rochester, Minnesota
| | - Allan Bieber
- Mayo Graduate School, Mayo Clinic, Rochester, Minnesota.,Department of Neurologic Surgery, Mayo Clinic, Rochester, Minnesota.,Department of Neurology, Mayo Clinic, Rochester, Minnesota
| | - Ju Ho Jeong
- Department of Neurologic Surgery, Mayo Clinic, Rochester, Minnesota
| | - Kevin E Bennet
- Department of Neurologic Surgery, Mayo Clinic, Rochester, Minnesota.,Division of Engineering, Mayo Clinic, Rochester, Minnesota
| | - J Luis Lujan
- Department of Neurologic Surgery, Mayo Clinic, Rochester, Minnesota.,Department of Physiology and Biomedical Engineering, Mayo Clinic, Rochester, Minnesota
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Abstract
Despite common comorbidity of sexual and urinary dysfunctions, the interrelationships between the neural control of these functions are poorly understood. The medullary reticular formation (MRF) contributes to both mating/arousal functions and micturition, making it a good site to test circuitry interactions. Urethane-anesthetized adult Wistar rats were used to examine the impact of electrically stimulating different nerve targets [dorsal nerve of the penis (DNP) or clitoris (DNC); L6/S1 trunk] on responses of individual extracellularly recorded MRF neurons. The effect of bladder filling on MRF neurons was also examined, as was stimulation of DNP on bladder reflexes via cystometry. In total, 236 MRF neurons responded to neurostimulation: 102 to DNP stimulation (12 males), 64 to DNC stimulation (12 females), and 70 to L6/S1 trunk stimulation (12 males). Amplitude thresholds were significantly different at DNP (15.0 ± 0.6 μA), DNC (10.5 ± 0.7 μA), and L6/S1 trunk (54.2 ± 4.6 μA), whereas similar frequency responses were found (max responses near 30–40 Hz). In five males, filling/voiding cycles were lengthened with DNP stimulation (11.0 ± 0.9 μA), with a maximal effective frequency plateau beginning at 30 Hz. Bladder effects lasted ∼2 min after DNP stimulus offset. Many MRF neurons receiving DNP/DNC input responded to bladder filling (35.0% and 68.3%, respectively), either just before (43%) or simultaneously with (57%) the voiding reflex. Taken together, MRF-evoked responses with neurostimulation of multiple nerve targets along with different responses to bladder infusion have implications for the role of MRF in multiple aspects of urogenital functions.
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Affiliation(s)
- C. H. Hubscher
- Department of Anatomical Sciences and Neurobiology, University of Louisville School of Medicine, Louisville, Kentucky; and
| | - D. S. Gupta
- Department of Anatomical Sciences and Neurobiology, University of Louisville School of Medicine, Louisville, Kentucky; and
| | - T. S. Brink
- Neuromodulation Research, Medtronic Incorporated, Minneapolis, Minnesota
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18
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Abstract
CONTEXT Spinal cord injury (SCI) results in a loss of function and sensation below the level of the lesion. Neuroprosthetic technology has been developed to help restore motor and autonomic functions as well as to provide sensory feedback. FINDINGS This paper provides an overview of neuroprosthetic technology that aims to address the priorities for functional restoration as defined by individuals with SCI. We describe neuroprostheses that are in various stages of preclinical development, clinical testing, and commercialization including functional electrical stimulators, epidural and intraspinal microstimulation, bladder neuroprosthesis, and cortical stimulation for restoring sensation. We also discuss neural recording technologies that may provide command or feedback signals for neuroprosthetic devices. CONCLUSION/CLINICAL RELEVANCE Neuroprostheses have begun to address the priorities of individuals with SCI, although there remains room for improvement. In addition to continued technological improvements, closing the loop between the technology and the user may help provide intuitive device control with high levels of performance.
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19
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Kim J, Basham E, Pedrotti KD. Geometry-based optimization of radio-frequency coils for powering neuroprosthetic implants. Med Biol Eng Comput 2012; 51:123-34. [PMID: 23086205 DOI: 10.1007/s11517-012-0975-8] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/07/2012] [Accepted: 10/05/2012] [Indexed: 11/25/2022]
Abstract
Biomedical implants powered by inductive links have several advantages over batteries or percutaneous power linkages. The inductive link power transfer efficiency must be optimized to realize the full advantage over other power delivery technologies. Optimization is also important to reduce the electromagnetic radiation exposure, reduce secondary heating effects and improve power efficiency, so that large primary side storage batteries are not required. Geometric constraints, i.e., size and shape, of biomedical implants are a primary concern of device design. In this paper, we present a novel coil optimization strategy driven by geometric constraints. By considering the relationship between wire diameter, number of turns, quality factor, coupling coefficient and shape of coil, we can optimize the inductively coupled coils to maximize the power transfer efficiency under stringent geometric constraints. This new approach is verified using a design example targeted for an intraocular visual prosthesis. In this example, we demonstrate an experimental power transfer efficiency of 52% by co-optimization of the primary and secondary coils.
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Affiliation(s)
- Jungsuk Kim
- Department of Computer Engineering, University of California at Santa Cruz, Santa Cruz, CA 95064, USA.
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