Estrogen replacement is protective to the effect of in vitro hypoxia on female rabbit bladder and pelvic floor contractile response

Amy D. Dobberfuhl,Catherine Schuler,Robert E. Leggett,Elise J.B. De,Robert M. Levin 대한비뇨의학회 2020 Investigative and Clinical Urology Vol.61 No.4

Purpose: To explore the effect of estrogen replacement on pelvic floor and bladder contractile response to electrical field stimulation, following in vitro hypoxia in an animal model of surgical menopause. Materials and Methods: Twelve female adult rabbits were divided into three groups: control, ovariectomy, and ovariectomy with estradiol replacement. At 4 weeks animals were euthanized. Bladder, coccygeus, and pubococcygeus were isolated. Tissues were equilibrated with oxygenated Tyrodes containing glucose and stimulated with electrical field stimulation. Tissues were then stimulated under hypoxic conditions for 1 hour using nitrogenated Tyrodes without glucose. Tissues were then re-oxygenated for 2 hours and stimulated. Results: Pelvic floor required 10 times the stimulation duration (power) to achieve maximum contraction at 2 g baseline tension (10 ms duration) when compared to bladder (1 ms duration). Maximal tension generated was significantly greater for bladder than pelvic floor. Coccygeus and pubococcygeus were significantly less sensitive to the effects of hypoxia and had stable contractile response to field stimulation throughout the hour of hypoxia. Hypoxia resulted in progressive and rapid decline of bladder contractile strength. Following hypoxia, pelvic floor contractile recovery was superior to bladder. Improvement in the contractile response of both bladder and pelvic floor, during the period of post-hypoxia re-oxygenation, was significantly greater in ovariectomy animals treated with estradiol replacement. Conclusions: Replacement of estradiol at time of ovariectomy reduced oxidative stress on tissue and was protective to the effects of hypoxia on pelvic floor and bladder contractile function.

Noxious electrical stimulation of the pelvic floor and vagina induces transient voiding dysfunction in a rabbit survival model of pelvic floor dystonia

Amy D. Dobberfuhl,Sara Spettel,Catherine Schuler,Robert M. Levin,Andrew H. Dubin,Elise J.B. De 대한비뇨의학회 2015 Investigative and Clinical Urology Vol.56 No.12

Purpose: Existing data supports a relationship between pelvic floor dysfunction and lower urinary tract symptoms. We developed a survival model of pelvic floor dysfunction in the rabbit and evaluated cystometric (CMG), electromyographic (EMG) and ambulatory voiding behavior. Materials and Methods: Twelve female adult virgin rabbits were housed in metabolic cages to record voiding and defecation. Anesthetized CMG/EMG was performed before and after treatment animals (n=9) received bilateral tetanizing needle stimulation to the pubococcygeous (PC) muscle and controls (n=3) sham needle placement. After 7 days all animals were subjected to tetanizing transvaginal stimulation and CMG/EMG. After 5 days a final CMG/EMG was performed. Results: Of rabbits that underwent needle stimulation 7 of 9 (78%) demonstrated dysfunctional CMG micturition contractions versus 6 of 12 (50%) after transvaginal stimulation. Needle stimulation of the PC musculature resulted in significant changes in: basal CMG pressure, precontraction pressure change, contraction pressure, interval between contractions and postvoid residual; with time to 3rd contraction increased from 38 to 53 minutes (p=0.008 vs. prestimulation). Vaginal noxious stimulation resulted in significant changes in: basal CMG pressure and interval between contractions; with time to 3rd contraction increased from 37 to 46 minutes (p=0.008 vs. prestimulation). Changes in cage parameters were primarily seen after direct needle stimulation. Conclusions: In a majority of animals, tetanizing electrical stimulation of the rabbit pelvic floor resulted in voiding changes suggestive of pelvic floor dysfunction as characterized by a larger bladder capacity, longer interval between contractions and prolonged contraction duration.

The artificial urinary sphincter and male sling for postprostatectomy incontinence: Which patient should get which procedure?

Craig V. Comiter,Amy D. Dobberfuhl 대한비뇨의학회 2016 Investigative and Clinical Urology Vol.57 No.1

Surgery is the most efficacious treatment for postprostatectomy incontinence. The ideal surgical approach depends on a variety of patient factors including history of prior incontinence surgery or radiation treatment, bladder contractility, severity of leakage, and patient expectations. Most patients choose to avoid a mechanical device, opting for the male sling over the artificial urinary sphincter. The modern male sling has continued to evolve with respect to device design and surgical technique. Various types of slings address sphincteric incompetence via different mechanisms of action. The recommended surgery, however, must be individualized to the patient based on degree of incontinence, detrusor contractility, and urethral compliance. A thorough urodynamic evaluation is indicated for the majority of patients, and the recommendation for an artificial urinary sphincter, a transobturator sling, or a quadratic sling will depend on urodynamic findings and the patient's particular preference. As advancements in this field evolve, and our understanding of the pathophysiology of incontinence and mechanisms of various devices improves, we expect to see continued evolution in device design.

The evolution of incontinence into resolved, refractory and de novo urgency urinary incontinence following sling placement at time of prolapse repair in a large urodynamic cohort

Xinyuan Zhang,Robyn K. Shaffer,Amy D. Dobberfuhl 대한비뇨의학회 2021 Investigative and Clinical Urology Vol.62 No.5

Purpose: To improve counseling in women at risk of refractory and/or de novo urgency urinary incontinence (UUI) following sling placement at time of prolapse repair, we created an outcome model to characterize changes in storage dysfunction. Materials and Methods: We identified 139 women who underwent urodynamics followed by sling or no sling placement at the time of prolapse repair over a 6-year period. Our primary outcome was the presence of UUI following sling placement. Data were analyzed in SAS using chi-square, Fisher's exact, Student's t-test, and Kaplan-Meier methods. Results: At baseline, the sling group had significantly higher subjective (62/81 [76.5%] vs. 18/58 [31.0%]; p<0.001), objective (62/81 [76.5%] vs. 6/58 [10.3%]; p<0.001), and occult (41/81 [50.6%] vs. 6/58 [10.3%]; p<0.001) stress urinary incontinence (SUI); and rates of subjective and objective UUI were similar to the no sling group prior to surgery. After surgery (mean follow-up 859 days) there was no difference with or without sling, in the rate of SUI (subjective, objective) and further SUI treatments (bulking agent, repeat sling). Higher rates of de novo (13/81 [16.0%] vs. 6/58 [10.3%]; p=0.454) and refractory (31/81 [38.3%] vs. 14/58 [24.1%]; p=0.048) UUI were noted in the sling group following surgery. On Kaplan-Meier analysis, a greater proportion of women in the no sling group did not report UUI at longest follow-up (hazard ratio 0.63; 95% confidence interval 0.37–1.06; p=0.081). Conclusions: Women should be counseled on the risk of de novo and refractory UUI following sling placement at time of prolapse repair.

Transvaginal ultrasound guided trigone and bladder injection: A cadaveric feasibility study for a novel route of intradetrusor chemodenervation

Raveen Syan,Mason A. Briggs,John C. Olivas,Sakti Srivastava,Craig V. Comiter,Amy D. Dobberfuhl 대한비뇨의학회 2019 Investigative and Clinical Urology Vol.60 No.1

Purpose: OnabotulinumtoxinA (BTX) detrusor chemodenervation is an efficacious third-line treatment for overactive bladder. Despite high clinical efficacy rates for BTX injection, many patients refuse initial or repeat treatment due to the invasiveness of the cystoscopic route of delivery. We assess the feasibility of injecting the trigone and posterior bladder wall via a transvaginal route under ultrasound guidance using a human cadaveric model. Materials and Methods: Eight de-identified anonymous fresh female deceased donor cadaver pelvises were placed in supine split leg position. A transvaginal ultrasound probe guided injections of India ink into the trigone in 3 sites and the posterior wall in 2 sites. Full thickness bladder biopsies were then obtained and histologic analysis was performed to confirm presence of India ink in the detrusor layer. Results: The mean time from day of death was 11.0 days (range, 4.0–23.0 days). Three to five bladder biopsies were obtained per cadaver, for a total of 34 specimens (20 trigone, 14 posterior wall). Histologic analysis revealed presence of India ink within the detrusor layer in 8/8 (100.0%) of cadavers. The surgeon's perception of appropriate targeting under ultrasound guidance was confirmed in 8/8 cadavers (100.0%) involving the bladder trigone, and 7/8 (87.5%) involving the posterior wall. Of injections that were believed to have appropriately targeted the detrusor layer, 22/34 specimens (64.7%) demonstrated the presence of India ink under histologic analysis. Conclusions: Intradetrusor injection of the bladder trigone and posterior wall under transvaginal ultrasound guidance is feasible and has acceptable accuracy.