MP54-13 DETECTION AND ASSESSMENT OF HEMORRHAGIC KIDNEY INJURY CAUSED BY BURST WAVE LITHOTRIPSY USING ULTRASOUND AND MAGNETIC RESONANCE IMAGING

Abstract

You have accessJournal of UrologyStone Disease: Shock Wave Lithotripsy1 Apr 2016MP54-13 DETECTION AND ASSESSMENT OF HEMORRHAGIC KIDNEY INJURY CAUSED BY BURST WAVE LITHOTRIPSY USING ULTRASOUND AND MAGNETIC RESONANCE IMAGING Adam Maxwell, Wayne Kreider, Yak-Nam Wang, Philip May, Donghoon Lee, Joshua Park, Bryan Cunitz, Mathew Sorensen, Rajash Handa, Michael Bailey, and Jonathan Harper Adam MaxwellAdam Maxwell More articles by this author , Wayne KreiderWayne Kreider More articles by this author , Yak-Nam WangYak-Nam Wang More articles by this author , Philip MayPhilip May More articles by this author , Donghoon LeeDonghoon Lee More articles by this author , Joshua ParkJoshua Park More articles by this author , Bryan CunitzBryan Cunitz More articles by this author , Mathew SorensenMathew Sorensen More articles by this author , Rajash HandaRajash Handa More articles by this author , Michael BaileyMichael Bailey More articles by this author , and Jonathan HarperJonathan Harper More articles by this author View All Author Informationhttps://doi.org/10.1016/j.juro.2016.02.583AboutPDF ToolsAdd to favoritesDownload CitationsTrack CitationsPermissionsReprints ShareFacebookTwitterLinked InEmail INTRODUCTION AND OBJECTIVES Burst wave lithotripsy (BWL) is a new, noninvasive method to disintegrate urinary tract stones by focused ultrasound pulses rather than shock waves. In order to evaluate the safety of this technique, preclinical work is needed to identify the effects of the BWL exposures on kidney tissue. This study investigated the use of ultrasound (US) imaging for real-time detection of hemorrhagic injury during BWL, as well as magnetic resonance imaging (MRI) for post-treatment quantification of injury in comparison with a standard morphometric technique. METHODS BWL exposures were delivered to 21 sites in 4 pigs by 170 and 335 kHz focused ultrasound transducers. A midline incision was made to open the abdomen, and the transducer was coupled through a water-filled cone directly to the kidney. During treatment, synchronized B-Mode and color Doppler ultrasound imaging were employed to monitor the transducer focal region to detect BWL-induced cavitation associated with hemorrhagic injury. After treatment, kidneys were perfusion-fixed and extracted for analysis. A 3T MRI scanner (Achieva, Philips Healthcare, The Netherlands) was used to obtain T1-weighted, T2-weighted, and susceptibility-weighted images of each of the 8 fixed kidneys. Hemorrhagic injury was then identified and volumetrically quantified from the three scans using 3D segmentation. The injury was also quantified in 5 of the kidneys by an established morphometric analysis technique that has been used to quantify injury in shock wave lithotripsy research. The detection of cavitation on US imaging was correlated with MRI and morphometric results. RESULTS During exposures, cavitation was identified on US images as hyperechoic regions in kidney tissue on B-Mode imaging and highly elevated Doppler power in the focal zone. Injury was clearly demarcated on MRI as a hypointense region on T2-weighted images. All injured volumes were <2% of the functional renal volume, and <0.5% for exposures anticipated to be used for BWL, measured either by MR or the traditional quantification method. Detection of cavitation on US was consistent with presence/absence of injury on MR in 20 of 24 sites (including untreated locations), and with morphometric analysis in 14 of 15 sites. Identified lesions on MRI coincided with results of morphometric analysis in 13 of 15 sites. CONCLUSIONS Ultrasound imaging is a sensitive detector of cavitation onset during BWL and correlates well with the presence of hemorrhagic tissue injury. MRI is a promising method to identify and quantify hemorrhagic kidney injury for BWL. © 2016FiguresReferencesRelatedDetails Volume 195Issue 4SApril 2016Page: e731 Advertisement Copyright & Permissions© 2016MetricsAuthor Information Adam Maxwell More articles by this author Wayne Kreider More articles by this author Yak-Nam Wang More articles by this author Philip May More articles by this author Donghoon Lee More articles by this author Joshua Park More articles by this author Bryan Cunitz More articles by this author Mathew Sorensen More articles by this author Rajash Handa More articles by this author Michael Bailey More articles by this author Jonathan Harper More articles by this author Expand All Advertisement Advertisement PDF downloadLoading ...