title: Restoration from acute urinary dysfunction using Utah electrode arrays implanted into the feline pudendal nerve.
abstract: OBJECTIVE
  To investigate intrafascicular pudendal nerve stimulation in felines as a means to restore urinary function in acute models of urinary incontinence, overactive bladder, and underactive bladder.
  
  
  METHODS
  Felines were anesthetized, and high-electrode-count (48 electrodes; 25 electrodes/mm(2) ) electrode arrays were implanted intrafascicularly into the pudendal nerve trunk. Electrodes were mapped for their ability to selectively or nonselectively excite the external anal sphincter, external urethral sphincter, and the detrusor bladder muscle. Statistical analysis was carried out to quantify reflexive voiding efficiencies, mean impedances of the microelectrodes used in this study, and to determine what differences, if any, in bladder contraction amplitudes were evoked by different electrode configurations.
  
  
  RESULTS
  Multielectrode arrays implanted into the pudendal nerve trunk were able to selectively and nonselectively excite genitourinary muscles. After inducing urinary incontinence with bilateral pudendal nerve transections (proximal to the implants), electrical stimulation delivered through certain microelectrodes was able to significantly reduce leaking (p = 0.008). Electrical stimulation delivered through detrusor selective electrodes was able to inhibit reflexive bladder contractions and excite bladder contractions, depending on the stimulation frequency. Specific electrode configurations were able to drive significantly (p < 0.001) larger bladder contractions than other electrode configurations, depending on the preparation. Successful reflexively or electrically driven bladder contractions were achieved in 46% and 38% of the preparations, respectively, an observation that has not been noted in previously published feline pudendal stimulation studies.
  
  
  CONCLUSIONS
  Multielectrode arrays implanted intrafascicularly into the pudendal nerve trunk may provide a promising new clinical neuromodulation therapy for the restoration of urinary function.
authors.affiliation: Department of Bioengineering, University of Utah, Salt Lake City, UT, USA.
authors.forename: Heather Anna Cary
authors.initials: HA
authors.lastname: Wark
authors.affiliation: Department of Bioengineering, University of Utah, Salt Lake City, UT, USA.
authors.forename: Shana R
authors.initials: SR
authors.lastname: Black
authors.affiliation: Department of Bioengineering, University of Utah, Salt Lake City, UT, USA.
authors.forename: Kiran Serah
authors.initials: KS
authors.lastname: Mathews
authors.affiliation: Department of Urology and Urological Surgery, University of Utah, Salt Lake City, UT, USA.
authors.forename: Patrick C
authors.initials: PC
authors.lastname: Cartwright
authors.affiliation: Department of Bioengineering, Case Western Reserve University, Cleveland, OH, USA.
authors.forename: Kenneth J
authors.initials: KJ
authors.lastname: Gustafson
authors.affiliation: Department of Bioengineering, University of Utah, Salt Lake City, UT, USA.
authors.forename: Richard Alan
authors.initials: RA
authors.lastname: Normann
mesh_terms: D000818:Animals; D002415:Cats; D004195:Disease Models, Animal; D004599:Electric Stimulation Therapy / Q000379:methods*; D004567:Electrodes, Implanted; D008297:Male; D009119:Muscle Contraction / Q000502:physiology; D009130:Muscle, Smooth / Q000502:physiology; D060525:Pudendal Nerve / Q000502:physiology*; D020127:Recovery of Function / Q000502:physiology*; D012018:Reflex / Q000502:physiology; D053201:Urinary Bladder, Overactive / Q000628:therapy; D014549:Urinary Incontinence / Q000628:therapy; D014555:Urination Disorders / Q000628:therapy*
keywords: Implanted nerve stimulation electrodes; pudendal nerve; urinary incontinence; urinary tract physiological processes