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Ureteral Calculi Detection Using Low Dose Computerized Tomography Protocols is Compromised in Overweight and Underweight Patients

2012; Lippincott Williams & Wilkins; Volume: 188; Issue: 1 Linguagem: Inglês

10.1016/j.juro.2012.02.2568

1527-3792

Jonathan P. Heldt, Jason C. Smith, Kirk M. Anderson, Gideon Richards, Gautum Agarwal, Damien Smith, Amy Schlaifer, Nicholas T. Pittenger, Daniel Han, Brenton D. Baldwin, Gabriel Schroeder, D. Duane Baldwin,

Radioactivity and Radon Measurements

No AccessJournal of UrologyAdult Urology1 Jul 2012Ureteral Calculi Detection Using Low Dose Computerized Tomography Protocols is Compromised in Overweight and Underweight Patients Jonathan P. Heldt, Jason C. Smith, Kirk M. Anderson, Gideon D. Richards, Gautum Agarwal, Damien L. Smith, Amy Schlaifer, Nicholas T. Pittenger, Daniel S. Han, Brenton D. Baldwin, Gabriel T. Schroeder, and D. Duane Baldwin Jonathan P. HeldtJonathan P. Heldt More articles by this author , Jason C. SmithJason C. Smith More articles by this author , Kirk M. AndersonKirk M. Anderson More articles by this author , Gideon D. RichardsGideon D. Richards More articles by this author , Gautum AgarwalGautum Agarwal More articles by this author , Damien L. SmithDamien L. Smith More articles by this author , Amy SchlaiferAmy Schlaifer More articles by this author , Nicholas T. PittengerNicholas T. Pittenger More articles by this author , Daniel S. HanDaniel S. Han More articles by this author , Brenton D. BaldwinBrenton D. Baldwin More articles by this author , Gabriel T. SchroederGabriel T. Schroeder More articles by this author , and D. Duane BaldwinD. Duane Baldwin Financial interest and/or other relationship with Onset Medical. More articles by this author View All Author Informationhttps://doi.org/10.1016/j.juro.2012.02.2568AboutFull TextPDF ToolsAdd to favoritesDownload CitationsTrack CitationsPermissionsReprints ShareFacebookLinked InTwitterEmail Abstract Purpose: Low dose computerized tomography protocols have demonstrated a reduction in radiation exposure while maintaining excellent sensitivity and specificity in the detection of stones in patients of average size. Low dose computerized tomography protocols have not yet been evaluated in subjects in the extremes of weight. We evaluated the effect of body weight when using low dose protocols to detect ureteral calculi. Materials and Methods: Three cadavers of increasing weight (55, 85 and 115 kg) were prepared by inserting 721 calcium oxalate stones (range 3 to 7 mm) in 33 random configurations into urinary tracts. Cadavers were then scanned using a GE LightSpeed® at 7 radiation settings. An independent, blinded review by a radiologist was conducted to generate ROC curves, with areas under the curve compared using a 1-way ANOVA (α = 0.05). Results: Sensitivity and specificity were significantly lower in the low and high weight cadavers compared to the medium weight cadaver at 5 mAs (p <0.001) and 7.5 mAs (p = 0.048). Differences in sensitivity and specificity at radiation settings of 15 mAs or greater were not significant. Conclusions: The sensitivity and specificity for the detection of ureteral calculi on computerized tomography were decreased for underweight and overweight subjects when using extremely low dose radiation settings (less than 1 mSv). 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Volume 188Issue 1July 2012Page: 124-129 Advertisement Copyright & Permissions© 2012 by American Urological Association Education and Research, Inc.Keywordstomographyureteral calculix-ray computeddiagnostic imagingnephrolithiasisradiation dosageAcknowledgmentsDrs. Bertha Escobar-Poni and Pedro Nava (Department of Anatomic Pathology, Loma Linda University) provided assistance. Udochukwu Oyoyo (consultant statistician, School of Public Health, Loma Linda University) designed and performed the statistical analysis.MetricsAuthor Information Jonathan P. Heldt More articles by this author Jason C. Smith More articles by this author Kirk M. Anderson More articles by this author Gideon D. Richards More articles by this author Gautum Agarwal More articles by this author Damien L. Smith More articles by this author Amy Schlaifer More articles by this author Nicholas T. Pittenger More articles by this author Daniel S. Han More articles by this author Brenton D. Baldwin More articles by this author Gabriel T. Schroeder More articles by this author D. Duane Baldwin Financial interest and/or other relationship with Onset Medical. More articles by this author Expand All Advertisement PDF downloadLoading ...