PD11-11 MODELING IN URODYNAMICS TO IDENTIFY DEFECTS IN THE URINARY SPHINCTER IN SITU
2014-03-28

You have accessJournal of UrologyUrodynamics/Incontinence/Female Urology: Incontinence Evaluation1 Apr 2014PD11-11 MODELING IN URODYNAMICS TO IDENTIFY DEFECTS IN THE URINARY SPHINCTER IN SITU Mario Klünder, Oliver Sawodny, Karl-Dietrich Sievert, Arnulf Stenzl, Ronny Feuer, and Michael Ederer Mario KlünderMario Klünder More articles by this author , Oliver SawodnyOliver Sawodny More articles by this author , Karl-Dietrich SievertKarl-Dietrich Sievert More articles by this author , Arnulf StenzlArnulf Stenzl More articles by this author , Ronny FeuerRonny Feuer More articles by this author , and Michael EdererMichael Ederer More articles by this author View All Author Informationhttps://doi.org/10.1016/j.juro.2014.02.544AboutPDF ToolsAdd to favoritesDownload CitationsTrack CitationsPermissionsReprints ShareFacebookTwitterLinked InEmail INTRODUCTION AND OBJECTIVES Urethral pressure profilometry is a common urodynamic tool used in the diagnosis of urinary incontinence. Raw data acquired from catheters is often difficult to interpret diagnostically, because potential angular fluctuations in the pressure profile may not be detected due to limited resolution and details may be concealed by sensor noise. We propose a new method that uses a mathematical model of the urethra to reconstruct the spatial pressure profile exerted by the sphincter in high detail definition. The proposed method addresses three shortcomings of urodynamics: Obtaining the spatial pressure profile on the outside of the urethra, dealing with low angular resolution, and sensor noise. METHODS We use a microtip-catheter with eight pressure sensors on the circumference in order to at least double the angular resolution compared to catheters in use today. An inclination sensor is located close to the eight sensors that determines the orientation of the catheter during retraction. The urethra is modeled as a linear elastic hollow cylinder and discretized via the Finite-Element-Method. We use an inverse algorithm to calculate the pressure profile on the outside circumference of the cylinder from pressure on the inside. Sensor size and –positions as well as areal sensitivity characteristics are taken into account explicitly. We use the catheter on a test stand, which features a silicone tube to simulate the urethra. RESULTS Simulation results show an accurate recovery of the pressure profile on the outside of the urethra. Numeric stability even in presence of sensor noise is ensured through regularization. Using the inverse algorithm, the pressure distribution around the tube can be recovered and points of interest located. The figure shows simulation results with the deformed outside and the inside of the urethra colored according to the pressure level. CONCLUSIONS With a mathematical model of the urethra and an inverse algorithm the pressure profile of the urethra is reconstructed through the use of a novel microtip catheter that provides sufficient data inside the urethra. Simulation and data results from the test stand demonstrate the accuracy of the proposed method. A reliable spatial reconstruction of the sphincter pressure profile may add diagnostic power in future clinical application. © 2014FiguresReferencesRelatedDetails Volume 191Issue 4SApril 2014Page: e290 Advertisement Copyright & Permissions© 2014MetricsAuthor Information Mario Klünder More articles by this author Oliver Sawodny More articles by this author Karl-Dietrich Sievert More articles by this author Arnulf Stenzl More articles by this author Ronny Feuer More articles by this author Michael Ederer More articles by this author Expand All Advertisement Advertisement PDF downloadLoading ...