ABSTRACTIntroduction and ObjectiveObservable autonomous rhythmic changes in intravesical pressure, termed bladder wall micromotion, is a phenomenon that has been linked to urinary urgency, the key symptom in overactive bladder (OAB). However, the mechanism through which micromotion drives urinary urgency is poorly understood. In addition, micromotion is inherently difficult to study in human urodynamics due to challenges distinguishing it from normal cyclic physiologic processes such as pulse rate, breathing, rectal contractions, and ureteral jetting. Therefore, the goal of this study was to create a reproducible model of micromotion using an ex‐vivo perfused porcine bladder, as well as to describe the relationship between micromotion and afferent nerve signaling.MethodsPorcine bladders were reanimated using ex‐vivo perfusion with a physiologic buffer. The pelvic nerve adjacent to the bladder was dissected, grasped with micro‐hook electrodes and electroneurogram (ENG) signals were recorded at 20 kHz. Bladders were catheterized and intravesical pressure measurements were taken using a Laborie XT Urodynamics system. Bladders were filled to a fixed volume of 300 mL and control measurements were recorded. The bladders were then washed with 0.001 M carbachol (CCh) solution and refilled to 300 mL to induce micromotion, which was detected as rhythmic changes in intravesical pressure. ENG amplitude was calculated in μV, and nerve firing rate was calculated as number of spikes above baseline threshold per minute.ResultsMicromotion was induced by carbachol in 12/25 (48.4%) of trials as rhythmic changes in intravesical pressure after the instillation of carbachol but not in any control period. A fast Fourier transform (FFT) algorithm showed average peak dominant frequency component amplitude was significantly higher during the carbachol period when compared to the control period (0.47 vs. 0.01 cm‐H2O, p < 0.0001). Peak waveform frequency (1.13 vs. 1.54 cycles/min, p > 0.05) did not differ between control and carbachol periods. With regard to afferent nerve signaling, normalized average amplitude (0.66 ± 0.24 vs. 0.05 ± 0.08 μV) and firing rate (0.68 ± 0.28 vs. 0.18 ± 0.22 spike/min) for all bladders was significantly greater in the carbachol period when compared to the control period (p < 0.001).ConclusionsMicromotion can be induced using instillation of carbachol in a perfused ex‐vivo porcine bladder. Increased afferent nerve firing is observed during periods of micromotion. Thus, micromotion may drive afferent nerve signaling and may potentially contribute to urinary urgency, detrusor overactivity, and OAB. The development of an experimental ex‐vivo porcine model for micromotion provides a reproducible method to study bladder micromotion and its potential role in the pathophysiology of urinary urgency and voiding dysfunction.

You have accessJournal of UrologyImaging/Uroradiology I (MP18)1 May 2024MP18-01 INCREASED PROVOKED BLADDER COMPLIANCE ASSOCIATED WITH HIGH URGENCY BOTHER IN A SUBSET OF WOMEN ≥50 YEARS OLD USING ULTRASOUND URODYNAMICS Michael Shields, Isabelle Pummill, Adam Vossenberg, Margaret Lefebvre, Christopher Keshishian, Julia Smolen, Sarah Kodama, Ria Khandpur, Jared Dunlap, Mina Ghatas, Linda Burkett, Lauren Siff, Ashley Carroll, Adam P. Klausner, and John E. Speich Michael ShieldsMichael Shields , Isabelle PummillIsabelle Pummill , Adam VossenbergAdam Vossenberg , Margaret LefebvreMargaret Lefebvre , Christopher KeshishianChristopher Keshishian , Julia SmolenJulia Smolen , Sarah KodamaSarah Kodama , Ria KhandpurRia Khandpur , Jared DunlapJared Dunlap , Mina GhatasMina Ghatas , Linda BurkettLinda Burkett , Lauren SiffLauren Siff , Ashley CarrollAshley Carroll , Adam P. KlausnerAdam P. Klausner , and John E. SpeichJohn E. Speich View All Author Informationhttps://doi.org/10.1097/01.JU.0001008672.83391.ed.01AboutPDF ToolsAdd to favoritesDownload CitationsTrack CitationsPermissionsReprints ShareFacebookLinked InTwitterEmail Abstract INTRODUCTION AND OBJECTIVE: Lower urinary tract symptoms can be caused by altered bladder compliance, which is calculated during urodynamics testing (UDT) as Δvolume/Δpressure. A novel "provoked compliance" calculation may be used to assess the bladder's response to compression. The objective of this study was to quantify provoked compliance in response to bladder compressions using ultrasound (US) – UDT. METHODS: Adult patients undergoing clinically indicated UDT were enrolled. Standard compliance (ΔV/ΔP), demographics, and ICIq-OAB surveys were recorded. Provoked compliance testing was initiated by pausing the pump at 50% capacity (based on 3-day void diary). A transverse US image was captured, serving as a baseline. The bladder was then compressed by the US probe to roughly half of the baseline anterior-posterior diameter for 5 seconds followed by a 5 second pause. This process was repeated 5x with transverse US images being captured during each compression and pause. ImageJ circularity function was utilized to calculate circularity by manually tracing the bladder wall in each captured image. Provoked compliance (Δcircularity/Δpressure) was then calculated by averaging circularity and pressure data across points of max compression. RESULTS: In data analyzed from 44 participants, there was significant association between age and increased provoked compliance, particularly with patients ≥50 years old compared to younger patients (p<0.05). Provoked compliance was >0.0275 cm-H2O-1 in 10/22 (45.5%) participants ≥50 years old compared to 0/12 (0%) in patients <50 years old (Figure 1A). Additionally, increased bother score (≥9) was associated with a higher likelihood of having a high provoked compliance (>0.0275 cm-H2O-1) compared to bother scores<9 (<0.0275 cm-H2O-1, p<0.05) (Figure 1B). There was no association between low filling compliance (<30 ml/cmH20) and provoked compliance (p>0.05). CONCLUSIONS: Higher provoked compliance (floppier bladders) during bladder compressions was seen in patients≥50 years old and those with increased bothersome urgency. Additional investigation is required to determine association with OAB and other forms of voiding dysfunction. Download PPT Source of Funding: NIH R01DK101719, NSF REU 1852116, VCU School of Medicine Summer Research Fellowship © 2024 by American Urological Association Education and Research, Inc.FiguresReferencesRelatedDetails Volume 211Issue 5SMay 2024Page: e300 Advertisement Copyright & Permissions© 2024 by American Urological Association Education and Research, Inc.Metrics Author Information Michael Shields More articles by this author Isabelle Pummill More articles by this author Adam Vossenberg More articles by this author Margaret Lefebvre More articles by this author Christopher Keshishian More articles by this author Julia Smolen More articles by this author Sarah Kodama More articles by this author Ria Khandpur More articles by this author Jared Dunlap More articles by this author Mina Ghatas More articles by this author Linda Burkett More articles by this author Lauren Siff More articles by this author Ashley Carroll More articles by this author Adam P. Klausner More articles by this author John E. Speich More articles by this author Expand All Advertisement PDF downloadLoading ...

You have accessJournal of UrologyBladder & Urethra: Anatomy, Physiology & Pharmacology (PD12)1 May 2024PD12-10 BLADDER WALL MICROMOTION CAN BE REPRODUCED USING AN EX-VIVO PERFUSED PORCINE BLADDER Ryan W. Fogg, Brendan McCormack, Michael Shields, Ashley Matthew, Gabby Grob, Nat Araia, Alice Strawn, Mina Ghatas, Linda S. Burkett, John E. Speich, and Adam P. Klausner Ryan W. FoggRyan W. Fogg , Brendan McCormackBrendan McCormack , Michael ShieldsMichael Shields , Ashley MatthewAshley Matthew , Gabby GrobGabby Grob , Nat AraiaNat Araia , Alice StrawnAlice Strawn , Mina GhatasMina Ghatas , Linda S. BurkettLinda S. Burkett , John E. SpeichJohn E. Speich , and Adam P. KlausnerAdam P. Klausner View All Author Informationhttps://doi.org/10.1097/01.JU.0001008772.30001.48.10AboutPDF ToolsAdd to favoritesDownload CitationsTrack CitationsPermissionsReprints ShareFacebookLinked InTwitterEmail Abstract INTRODUCTION AND OBJECTIVE: Bladder wall micromotion (BMM) may play a role in the pathophysiology of overactive bladder (OAB). However, BMM is inherently difficult to study in human urodynamics due to challenges distinguishing micromotion from normal cyclic physiologic processes such as pulse rate, breathing, rectal contractions, and ureteral jetting. Therefore, the goal to this study was to create a reproducible model of BMM using an ex-vivo perfused porcine bladder. METHODS: Porcine bladders, along with the vascular tree were harvested. The vesical arteries were cannulated and ex-vivo bladder perfusion was performed using physiologic MOPS (3-(N-morpholino) propanesulfonic acid) buffer solution (Figure 1A). Using a Laborie XT urodynamics system, bladders were filled with saline to a constant volume of 300 mL and control pressures were recorded. The bladders were then flushed with a 0.001 M carbachol solution and intravesical pressure measurements were taken. Recorded rhythmic pressure wave forms were analyzed for frequency and amplitude using a fast Fourier transform (FFT) analysis. Control and micromotion periods were compared using a paired T-test. RESULTS: BMM was observed in 12/28 (43%) of harvested bladders. The average baseline pressure at which BMM was observed was 19 cm H2O. Pig sex, weight, and ischemia time were not associated with the detection of BMM (p>0.05). BMM was not observed in the control period during any trial and was observed only after carbachol instillation as rhythmic pressure changes (Figure 1B and 1C). FFT analysis was performed for each bladder where micromotion (threshold of peak amplitude>0.18 cmH2O) was observed to visualize peak frequencies and amplitudes (Figure 1D and 1E). The average peak BMM amplitude (0.01 vs 0.47 cm H2O, p<0.0001) was significantly higher during the micromotion period. However, frequency (1.54 vs 1.13 cycles/min, p>0.05) did not differ between control and micromotion periods. CONCLUSIONS: BMM can be induced using instillation of carbachol in a perfused ex-vivo porcine bladder. The development of an experimental ex-vivo porcine model for micromotion provides a reproducible method to study bladder micromotion and its potential role in the pathophysiology of OAB. Download PPT Source of Funding: NIH Grant # R01-DK101719, VCU School of Medicine Dean's Summer Research Fellowship © 2024 by American Urological Association Education and Research, Inc.FiguresReferencesRelatedDetails Volume 211Issue 5SMay 2024Page: e260 Advertisement Copyright & Permissions© 2024 by American Urological Association Education and Research, Inc.Metrics Author Information Ryan W. Fogg More articles by this author Brendan McCormack More articles by this author Michael Shields More articles by this author Ashley Matthew More articles by this author Gabby Grob More articles by this author Nat Araia More articles by this author Alice Strawn More articles by this author Mina Ghatas More articles by this author Linda S. Burkett More articles by this author John E. Speich More articles by this author Adam P. Klausner More articles by this author Expand All Advertisement PDF downloadLoading ...

You have accessJournal of UrologyCME1 Apr 2023MP60-11 A PRELIMINARY STUDY OF SEX DIFFERENCES IN PREFRONTAL CORTICAL OXYHEMOGLOBIN CONCENTRATION DURING NATURAL BLADDER FILLING Gabrielle Grob, Helen Query, Linda S. Burkett, Peter Daniels, Mina P. Ghatas, Michael Shields, Devin Rogers, abigail Kaufmann, Lynn Stothers, Adam P. Klausner, and John E. Speich Gabrielle GrobGabrielle Grob More articles by this author , Helen QueryHelen Query More articles by this author , Linda S. BurkettLinda S. Burkett More articles by this author , Peter DanielsPeter Daniels More articles by this author , Mina P. GhatasMina P. Ghatas More articles by this author , Michael ShieldsMichael Shields More articles by this author , Devin RogersDevin Rogers More articles by this author , abigail Kaufmannabigail Kaufmann More articles by this author , Lynn StothersLynn Stothers More articles by this author , Adam P. KlausnerAdam P. Klausner More articles by this author , and John E. SpeichJohn E. Speich More articles by this author View All Author Informationhttps://doi.org/10.1097/JU.0000000000003318.11AboutPDF ToolsAdd to favoritesDownload CitationsTrack CitationsPermissionsReprints ShareFacebookLinked InTwitterEmail Abstract INTRODUCTION AND OBJECTIVE: Sex differences during bladder filling are poorly understood. Functional near infrared spectroscopy (fNIRS) allows non-invasive measurement of cortical brain oxygenated hemoglobin concentration (O2Hb), which has been shown to increase during bladder filling. The objective of this study was to use fNIRS to compare differences between sexes in cortical O2Hb during natural bladder filling. METHODS: Control participants with no known urologic conditions and a negative urgency screen (ICIq-OAB and OAB-V3 surveys) completed a validated oral hydration protocol. During the protocol, participants recorded real-time sensation of bladder fullness (0-100%) and reported “first desire” to void using a Sensation Meter. Prefrontal cortical fNIRS continuous recording of O2Hb was completed during filling and voiding with a 24 channel template. Matlab was used to analyze data between “first desire” to void and 100% sensation, defined in this study as the period of “elevated urgency.” Channels were sub-divided by cortical regions: right (9), left (9), middle (6). RESULTS: Male (n=4) and female (n=4) participants were enrolled with mean age of 39 years and BMI of 25. There were no differences in age, BMI, race, daily fluid intake or OAB scores between sexes. Mean time between first desire and 100% sensation (minutes) was 12.9±6.01 and did not differ between groups (13.8±7.97 female vs 12.0±4.3 male, p=0.70). The difference in O2Hb throughout high urgency was similar between groups in each of the 24 individual channels, with greatest changes in the lateral prefrontal cortex (figure 1). The association between the change in O2Hb and filling did not differ between sexes (R-squared > 0.5 in 72.9% females and 82.3% males, p=0.27). O2Hb generally increased with a positive slope of the exponential fitted curve in 92% participants and did not differ between sexes by individual participant or in all 24 channels. CONCLUSIONS: We found that prefrontal cortical O2Hb concentration generally increases during natural filling and does not appear to differ between male and female controls. Ultimately, fNIRS might enable objective identification of specific neuroexcitation patterns to allow office-based diagnosis and improved treatment of voiding dysfunction. Source of Funding: NIH R21DK128649 & K12HD108269, VCU Presidential Research Quest Fund © 2023 by American Urological Association Education and Research, Inc.FiguresReferencesRelatedDetails Volume 209Issue Supplement 4April 2023Page: e847 Advertisement Copyright & Permissions© 2023 by American Urological Association Education and Research, Inc.MetricsAuthor Information Gabrielle Grob More articles by this author Helen Query More articles by this author Linda S. Burkett More articles by this author Peter Daniels More articles by this author Mina P. Ghatas More articles by this author Michael Shields More articles by this author Devin Rogers More articles by this author abigail Kaufmann More articles by this author Lynn Stothers More articles by this author Adam P. Klausner More articles by this author John E. Speich More articles by this author Expand All Advertisement PDF downloadLoading ...

You have accessJournal of UrologyCME1 Apr 2023MP60-06 INCREASE IN AFFERENT PELVIC NERVE FIRING DURING CONTINUOUS FILLING IN AN ISOLATED PERFUSED PORCINE BLADDER MODEL Devin Rogers, R. Hart Moore, Mina P. Ghatas, Christopher Bednarz, Gabrielle Grob, Michael Shields, Linda S. Burkett, Selvaraj Muthusamy, John E. Speich, and Adam P. Klausner Devin RogersDevin Rogers More articles by this author , R. Hart MooreR. Hart Moore More articles by this author , Mina P. GhatasMina P. Ghatas More articles by this author , Christopher BednarzChristopher Bednarz More articles by this author , Gabrielle GrobGabrielle Grob More articles by this author , Michael ShieldsMichael Shields More articles by this author , Linda S. BurkettLinda S. Burkett More articles by this author , Selvaraj MuthusamySelvaraj Muthusamy More articles by this author , John E. SpeichJohn E. Speich More articles by this author , and Adam P. KlausnerAdam P. Klausner More articles by this author View All Author Informationhttps://doi.org/10.1097/JU.0000000000003318.06AboutPDF ToolsAdd to favoritesDownload CitationsTrack CitationsPermissionsReprints ShareFacebookLinked InTwitterEmail Abstract INTRODUCTION AND OBJECTIVE: While urodynamics testing is routinely used to evaluate voiding dysfunction, the tests are expensive, invasive, poorly reproducible, and prone to artifacts. There is a pressing need to develop next-generation urodynamics. The purpose of this study was to develop an ex-vivo porcine bladder model to measure afferent pelvic nerve signaling that can be used as a platform for novel urodynamic tools. METHODS: Porcine bladders with attached ureters and vascular supply were harvested from local abattoirs and perfused with physiologic buffer. Micro-hook electrodes were attached to the pelvic nerve on the posterior of the bladder and electroneurogram (ENG) signals were recorded at 20KHz. Each bladder was filled with 1 liter of saline over 10 minutes using standard urodynamics equipment which simultaneously recorded intravesical pressure (Figure 1A). Nerve amplitude was calculated as the area under the curve (AUC) for each minute and nerve firing rate was calculated as number of nerve spikes (above baseline threshold) per minute. At the conclusion of the experiment, samples of the nerve were collected and processed for histological analysis (H&E and S100 stains). RESULTS: A total of 9 pig bladders were used. A pathologist confirmed the presence of nerve in all adequately processed samples. Vesical pressure, nerve firing rate, and nerve amplitude were all found to increase with bladder filling (Figure 1B). During filling tertiles (low fill: min 1-3, med fill: min 4-6, and high fill: min 7-10), pressures were 0.22±0.04, 0.38±0.05 and 0.72±0.07 (cmH20). Nerve firing rates were 0.08±0.03, 0.31±0.06 and 0.43±0.04 spikes/minute, respectively, and nerve amplitudes were 0.11±0.06, 0.39±0.06 and 0.56±0.14 μV. There were strong relationships between average normalized pressure values and averaged normalized nerve firing rate (r2=0.66) as well as average normalized nerve amplitude (r2=0.8). CONCLUSIONS: The ex-vivo perfused porcine bladder model can reproducibly measure afferent nerve activity that correlates with intravesical pressure during filling. This protocol can be used as a preclinical model for the development of next-generation urodynamics technologies and could potentially be used as a surrogate measure of bladder sensation. Source of Funding: NIH R01-DK101719 & VCU Endeavour Legacy Foundation © 2023 by American Urological Association Education and Research, Inc.FiguresReferencesRelatedDetails Volume 209Issue Supplement 4April 2023Page: e844 Advertisement Copyright & Permissions© 2023 by American Urological Association Education and Research, Inc.MetricsAuthor Information Devin Rogers More articles by this author R. Hart Moore More articles by this author Mina P. Ghatas More articles by this author Christopher Bednarz More articles by this author Gabrielle Grob More articles by this author Michael Shields More articles by this author Linda S. Burkett More articles by this author Selvaraj Muthusamy More articles by this author John E. Speich More articles by this author Adam P. Klausner More articles by this author Expand All Advertisement PDF downloadLoading ...

INTRODUCTION AND OBJECTIVES:Urodynamics are the accepted gold standard for the evaluation of multiple forms of voiding dysfunction. However, the tests are expensive, invasive, poorly reproducible, and often prone to artifacts. Therefore, there is a pressing need to develop next-generation urodynamics. The purpose of this study was to develop a novel ex vivo porcine bladder urodynamics model with afferent pelvic nerve signaling that can be used as a preclinical surrogate for bladder sensation. METHODS:Porcine bladders including the ureters and vascular supply were harvested from local abattoirs using an established protocol in both male and female animals. Ex vivo bladder perfusion was performed using physiologic MOPS (3-(N-morpholino) propanesulfonic acid) buffer solution. The pelvic nerve adjacent to the bladder was grasped with micro-hook electrodes and electroneurogram (ENG) signals recorded at 20 kHz. Bladders were filled with saline at a nonphysiologic rate (100 mL/min) to a volume of 1 L using standard urodynamics equipment to simultaneously record intravesical pressure. ENG amplitude was calculated as the area under the curve for each minute, and ENG firing rate was calculated as number of spikes (above baseline threshold) per minute. At the conclusion of the experiment, representative nerve samples were removed and processed for nerve histology by a pathologist (hematoxylin and eosin and S100 stains). RESULTS:A total of 10 pig bladders were used, and nerve histology confirmed the presence of nerve in all adequately processed samples. Vesical pressure, ENG firing rate, and ENG amplitude all increased as a function of filling. During filling tertiles (low fill: min 1-3, med fill: min 4-6, and high fill: min 7-10), normalized pressures were 0.22 ± 0.04, 0.38 ± 0.05, and 0.72 ± 0.07 (cmH2O). Similarly, normalized ENG firing rates were 0.08 ± 0.03, 0.31 ± 0.06, and 0.43 ± 0.04 spikes/minute, respectively, and normalized nerve amplitudes were 0.11 ± 0.06, 0.39 ± 0.06, and 0.56 ± 0.14) μV, respectively. Strong relationships between average normalized pressure values and averaged normalized ENG firing rate (r2  = 0.66) and average normalized ENG amplitude (r2  = 0.8) were identified. CONCLUSIONS:The ex vivo perfused porcine bladder can be used as a preclinical model for the development of next-generation urodynamics technologies. Importantly, the model includes a reproducible method to measure afferent nerve activity that directly correlates with intravesical pressure during filling and could potentially be used as a surrogate measure of bladder sensation.

Background: Functional near infrared spectroscopy (fNIRS) is a versatile, noninvasive, and inexpensive tool that can be used to measure oxyhemoglobin (O2Hb) changes in the cortical brain caused by increasing bladder sensation during filling in upright posture. This study’s purpose is to provide a rigorous methodologic template that can be implemented for comparative studies of fNIRS in the diagnosis and management of lower urinary tract symptoms including overactive bladder (OAB) and other forms of lower urinary tract dysfunction. Methods: Participants without any urologic conditions completed a validated oral hydration protocol facilitating and equilibrating natural bladder filling. First desire to void and real time bladder sensation (0–100%) were recorded using a Sensation Meter. A 24-channel fNIRS template simultaneously recorded prefrontal cortical O2Hb. Each channel was analyzed between “first desire” to void and 100% sensation, defined in this study as the period of “high sensation”. Channels were sub-divided by cortical regions: right (nine channels), left (nine channels), middle (six channels). Results: A total of eight participants (male: n=4, female: n=4) were enrolled with mean age 39±19.9 years and body mass index (BMI) of 25±3.93 kg/m2. There were no differences in age, BMI, race, or OAB survey scores based on biological sex. Signal acquisition improved with power bank use, postural head support for motion reduction, and head cap optimization. Acceleration-based concurrent motion measurement was effectively utilized to remove motion artifacts. O2Hb concentration patterns appeared irregular during low sensation and increased during high sensation after first desire across the frontal cortex. Conclusions: Employing a stepwise approach, this study defined a methodological guide for improved prefrontal fNIRS signal acquisition and analysis during bladder filling. The technique demonstrated that prefrontal fNIRS cortical O2Hb increases with elevated bladder sensation in normal subjects and sets the stage for comparative studies in individuals with OAB and other forms of lower urinary tract dysfunction.

You have accessJournal of UrologyCME1 May 2022MP07-04 DEVELOPMENT OF A PORCINE MODEL TO QUANTIFY AFFERENT NERVE SIGNALING: A PRELIMINARY STUDY Christopher Bednarz, Michael Shields, Graham Pingree, Abraham Alattar, David Lester, Ashley Cardenas, Sean Bryant, William Visser, John Speich, and Adam Klausner Christopher BednarzChristopher Bednarz More articles by this author , Michael ShieldsMichael Shields More articles by this author , Graham PingreeGraham Pingree More articles by this author , Abraham AlattarAbraham Alattar More articles by this author , David LesterDavid Lester More articles by this author , Ashley CardenasAshley Cardenas More articles by this author , Sean BryantSean Bryant More articles by this author , William VisserWilliam Visser More articles by this author , John SpeichJohn Speich More articles by this author , and Adam KlausnerAdam Klausner More articles by this author View All Author Informationhttps://doi.org/10.1097/JU.0000000000002529.04AboutPDF ToolsAdd to favoritesDownload CitationsTrack CitationsPermissionsReprints ShareFacebookLinked InTwitterEmail Abstract INTRODUCTION AND OBJECTIVE: Afferent nerve signals in response to bladder filling are a critical component in the normal micturition cycle. It is proposed that aberrations in signaling may be associated with voiding dysfunction. The purpose of this study was to develop a model to capture afferent nerve signals in perfused porcine bladders. To our knowledge this is a model that has not been previously reported. METHODS: Porcine bladders were harvested fresh from local abattoirs. Ex vivo bladders were stored in physiologic buffer solution and prepared for experimentation by intubation of vesicular arteries, ligation of bilateral ureters, and cannulation of the urethra with both a Urodynamics catheter and a length of 1/8 inch tubing (Figure 1A). Nerves were isolated and loop electrodes were placed to monitor signaling activity using an AD Instruments PL2604 Power Lab (Figure 1B). To preserve bladder integrity, vesicular arteries were perfused with physiologic buffer solution. Bladders were filled with deionized water from a volume of 0 to 1000 mL. Urodynamic tracings were monitored for pressure change with filling. Nerve fibers were monitored for propagation of electrical signals consistent with nerve firing. RESULTS: Three porcine bladders were used for this study. In all animals a phasic afferent signal was identified (Figure 2A). Bursts of activity were noted at an average volume of 351 cc. The signal occurred over a period averaging 4 seconds with a frequency of 8 hz and amplitude of 0.65mV. An additional signal (Figure 2B) was observed (n=1) where signal activity corresponded to filling volume (Figure 2C). Nerves emanating from the posterior aspect of the bladder (n=1) were isolated and confirmed using H&E immunohistochemistry. CONCLUSIONS: This experiment demonstrated that a perfused porcine bladder model can be used to identify afferent nerve signaling in response to filling. This is the first study of its type to use perfused porcine bladders. Application of this model to ongoing studies may be useful as an objective method to study bladder afferent function. Source of Funding: NIH Grant R01DK101719 © 2022 by American Urological Association Education and Research, Inc.FiguresReferencesRelatedDetails Volume 207Issue Supplement 5May 2022Page: e116 Advertisement Copyright & Permissions© 2022 by American Urological Association Education and Research, Inc.MetricsAuthor Information Christopher Bednarz More articles by this author Michael Shields More articles by this author Graham Pingree More articles by this author Abraham Alattar More articles by this author David Lester More articles by this author Ashley Cardenas More articles by this author Sean Bryant More articles by this author William Visser More articles by this author John Speich More articles by this author Adam Klausner More articles by this author Expand All Advertisement PDF downloadLoading ...