2305 NOVEL USE OF MRI TO DETECT REFLUX IN A BLADDER MODEL WITHOUT CATHETERS, IONIZING RADIATION, OR CONTRAST… OH MY!

Abstract

You have accessJournal of UrologyImaging/Radiology: Uroradiology1 Apr 20112305 NOVEL USE OF MRI TO DETECT REFLUX IN A BLADDER MODEL WITHOUT CATHETERS, IONIZING RADIATION, OR CONTRAST… OH MY! Bhavin Patel, Gordon McLorie, Anthony Atala, Robert Kraft, and Steven Hodges Bhavin PatelBhavin Patel Winston Salem, NC More articles by this author , Gordon McLorieGordon McLorie Winston Salem, NC More articles by this author , Anthony AtalaAnthony Atala Winston Salem, NC More articles by this author , Robert KraftRobert Kraft Winston Salem, NC More articles by this author , and Steven HodgesSteven Hodges Winston Salem, NC More articles by this author View All Author Informationhttps://doi.org/10.1016/j.juro.2011.02.2551AboutPDF ToolsAdd to favoritesDownload CitationsTrack CitationsPermissionsReprints ShareFacebookTwitterLinked InEmail INTRODUCTION AND OBJECTIVES Novel scanning and processing protocols have been developed to augment the diagnostic ability of magnetic resonance imaging (MRI). Single Shot Fast Spin Echo pulse sequencing (SSFSE) is one such technology. It allows one to image directional flow independent of contrast. We propose that using this technology, unenhanced urine can be used as an endogenous tracer, allowing for the measurement of urine flow back to the kidney. This could allow for the diagnosis of reflux without a catheter, contrast agent, or ionizing radiation. METHODS A model of the urinary tract was created with a “bladder” (reservoir and pump) designed to move normal saline along two 3mm diameter plastic tubes “ureters” at a rate mimicking urine flow, 3–5 mm/sec. In the MRI scanner, the protons of the fluid in the ‘bladder' were excited in a 90 degree axial spin. As the urine moved into the ureters a 180 degree pulse was performed along the sagittal plane. With reflux present (flow up the tubes), the fluid excited by the 90 degree pulse would leave the reservoir, but since it is constrained by the tubes it would also be excited by the 180 degree pulse. Only fluids that “see” both RF pulses are visible in the SSFSE sequencing, so only refluxing urine would enhance. RESULTS Performing the described modification of SSFSE MRI, we were able to excite the fluid in the model bladder for approximately 4 seconds, allowing the visualization of fluid reflux up the model urinary tract without the use of contrast agents. The temporal resolution was in the millisecond range. CONCLUSIONS Using a modification of a SSFSE, we were able to detect retrograde flow in a model ureter and bladder system using MRI. We hope to apply this technology to allow us to detect reflex in children without contrast, catheterization or ionizing radiation. © 2011 by American Urological Association Education and Research, Inc.FiguresReferencesRelatedDetails Volume 185Issue 4SApril 2011Page: e924 Peer Review Report Advertisement Copyright & Permissions© 2011 by American Urological Association Education and Research, Inc.MetricsAuthor Information Bhavin Patel Winston Salem, NC More articles by this author Gordon McLorie Winston Salem, NC More articles by this author Anthony Atala Winston Salem, NC More articles by this author Robert Kraft Winston Salem, NC More articles by this author Steven Hodges Winston Salem, NC More articles by this author Expand All Advertisement Advertisement PDF downloadLoading ...