MP38-06 ULTRA LOW DOSE CT-KUB TO DETECT KIDNEY STONES WITH 44% LESS RADIATION: IS THE PLAIN RADIOGRAPH OBSOLETE?

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You have accessJournal of UrologyStone Disease: Surgical Therapy IV1 Apr 2015MP38-06 ULTRA LOW DOSE CT-KUB TO DETECT KIDNEY STONES WITH 44% LESS RADIATION: IS THE PLAIN RADIOGRAPH OBSOLETE? Ben H. Chew, Patrick McLaughlin, Ryan F. Paterson, Elspeth M. McDougall, James Nugent, Allen V. Rowley, Jean Buckley, and Charles Zwirewich Ben H. ChewBen H. Chew More articles by this author , Patrick McLaughlinPatrick McLaughlin More articles by this author , Ryan F. PatersonRyan F. Paterson More articles by this author , Elspeth M. McDougallElspeth M. McDougall More articles by this author , James NugentJames Nugent More articles by this author , Allen V. RowleyAllen V. Rowley More articles by this author , Jean BuckleyJean Buckley More articles by this author , and Charles ZwirewichCharles Zwirewich More articles by this author View All Author Informationhttps://doi.org/10.1016/j.juro.2015.02.1381AboutPDF ToolsAdd to favoritesDownload CitationsTrack CitationsPermissionsReprints ShareFacebookTwitterLinked InEmail INTRODUCTION AND OBJECTIVES At our institution, Kidney-Ureter-Bladder (KUB) radiographs are performed immediately prior to shockwave lithotripsy (SWL). Conventional low dose CT-KUBs (radiation effective dose of 2.2-3.0 mSv) are only performed if stones are not visible on KUB. Recent advances in CT detector design and image reconstruction algorithms have made sub-milliSievert ultra-low dose CT (ULDCT) acquisition feasible, but the diagnostic performance of these exams has not yet been reported. We sought to compare the radiation dose and diagnostic performance of ULDCT to KUB in patients prior to SWL. We hypothesized that ULDCT would provide at least the same amount of information as a KUB immediately prior to SWL. METHODS Patients enrolled in this study consented and received both a KUB radiograph and an ULDCT prior to SWL. If no stones were identified, then a standard low dose abdominal CT was obtained. Radiation exposure parameters were recorded and both examinations were read in random order by blinded radiologists to determine the correlation between the two modalities. RESULTS 51 patients (M:F, 34:17) with a mean age of 56.2 ± 13.8y were enrolled. The effective radiation dose was significantly lower with ULDCT (0.28 ±0.10 mSv) compared to KUB (0.50±0.10 mSv, p=0.014). The number of stones seen on both modalities was equivalent: KUB was 1.59±1.27 vs 1.92±01.51 for ULDCT (p=0.35). Measurement of stone size was equivalent using ULDCT (6.47±3.34mm) compared to KUB (6.98±3.41mm, p=0.455). In 3 cases (5.9%), the ULDCT helped localize ureteral stones that were not visible on KUB. ULDCT altered treatment priority of treating the ureteral stones first. CONCLUSIONS Sub-milliSievert ULDCT delivers 44% less radiation than a plain KUB radiograph and was equivalent in detecting the number and size of stones. In 5.9% of cases, CT localized stones prior to SWL better than KUB. In future, ULDCT may replace KUB as it delivers less radiation with potentially more information immediately prior to SWL. Validation of this technology in the acute care setting in the Emergency Room will be necessary. © 2015 by American Urological Association Education and Research, Inc.FiguresReferencesRelatedDetails Volume 193Issue 4SApril 2015Page: e448 Advertisement Copyright & Permissions© 2015 by American Urological Association Education and Research, Inc.MetricsAuthor Information Ben H. Chew More articles by this author Patrick McLaughlin More articles by this author Ryan F. Paterson More articles by this author Elspeth M. McDougall More articles by this author James Nugent More articles by this author Allen V. Rowley More articles by this author Jean Buckley More articles by this author Charles Zwirewich More articles by this author Expand All Advertisement Advertisement PDF downloadLoading ...