PD27-05 BENCHTOP BLADDER PHANTOM PRESSURE ESTIMATION USING ULTRASOUND CONTRAST AGENTS

Abstract

You have accessJournal of UrologyUrodynamics/Lower Urinary Tract Dysfunction/Female Pelvic Medicine: Basic Research & Pathophysiology (PD27)1 Sep 2021PD27-05 BENCHTOP BLADDER PHANTOM PRESSURE ESTIMATION USING ULTRASOUND CONTRAST AGENTS Kourosh Kalayeh, J. Brian Fowlkes, Jake Claflin, Mario L. Fabiilli, William W. Schultz, and Bryan S. Sack Kourosh KalayehKourosh Kalayeh More articles by this author , J. Brian FowlkesJ. Brian Fowlkes More articles by this author , Jake ClaflinJake Claflin More articles by this author , Mario L. FabiilliMario L. Fabiilli More articles by this author , William W. SchultzWilliam W. Schultz More articles by this author , and Bryan S. SackBryan S. Sack More articles by this author View All Author Informationhttps://doi.org/10.1097/JU.0000000000002020.05AboutPDF ToolsAdd to favoritesDownload CitationsTrack CitationsPermissionsReprints ShareFacebookLinked InTwitterEmail Abstract INTRODUCTION AND OBJECTIVE: Lack of a catheter-free, physiological method for evaluating bladder pressure is considered to be a major challenge in urodynamic testing. We hypothesize that pressure sensitive acoustic properties of ultrasound contrast agents (UCAs)–a method known as SubHarmonic Aided Pressure Estimation (SHAPE)–adequately estimates benchtop bladder phantom pressures. METHODS: The designed bladder phantom simulates non-voiding contractions (NVCs) and variable compliance. Laboratory made equivalent of a commercial UCA is diluted in 0.9 % normal saline (0.08 % v/v) and infused using urodynamic equipment (30 ml/min). Simultaneous subharmonic signal scattered by UCAs is acquired with ultrasound scanner (GE LOGIQ E10 and C2-9 probe using SHAPE mode) and calibrated with a linear fit to yield bladder pressure values. For the variable compliance bladder model, measurements are obtained at 10 cmH2O pressure increments while for the NVC model measurements are acquired continuously. RESULTS: Examples of pressure tracings and SHAPE estimations for the two models are shown. The maximum absolute errors for variable compliance and NVCs are less than 8 cmH2O (8 %) and 16 cmH2O (16 %), respectively. The mean R−squared values for both models (n=4) is R2=0.89±0.09. CONCLUSIONS: Subharmonic signal scattered by UCAs can be strongly correlated with phantom bladder pressures. This is the first step towards creating a catheter-free voiding bladder pressure measurement using SHAPE. Source of Funding: Societies for Pediatric Urology and UofM Mcubed © 2021 by American Urological Association Education and Research, Inc.FiguresReferencesRelatedDetails Volume 206Issue Supplement 3September 2021Page: e444-e445 Advertisement Copyright & Permissions© 2021 by American Urological Association Education and Research, Inc.MetricsAuthor Information Kourosh Kalayeh More articles by this author J. Brian Fowlkes More articles by this author Jake Claflin More articles by this author Mario L. Fabiilli More articles by this author William W. Schultz More articles by this author Bryan S. Sack More articles by this author Expand All Advertisement Loading ...