2214 AN ELLIPSOID MODEL OF THE KIDNEY CALCULATED FROM MULTIDETECTOR COMPUTED TOMOGRAPHY PREDICTS DIFFERENTIAL FUNCTION IN LIVING RELATED DONORS

Abstract

You have accessJournal of UrologyImaging/Radiology: Uroradiology1 Apr 20112214 AN ELLIPSOID MODEL OF THE KIDNEY CALCULATED FROM MULTIDETECTOR COMPUTED TOMOGRAPHY PREDICTS DIFFERENTIAL FUNCTION IN LIVING RELATED DONORS John Henderson, Maitham Moslim, Matthew Knox, and Nigel Cowan John HendersonJohn Henderson High Wycombe, United Kingdom More articles by this author , Maitham MoslimMaitham Moslim Damascus, Syrian Arab Republic More articles by this author , Matthew KnoxMatthew Knox Calgary, Canada More articles by this author , and Nigel CowanNigel Cowan Oxford, United Kingdom More articles by this author View All Author Informationhttps://doi.org/10.1016/j.juro.2011.02.2454AboutPDF ToolsAdd to favoritesDownload CitationsTrack CitationsPermissionsReprints ShareFacebookTwitterLinked InEmail INTRODUCTION AND OBJECTIVES Computed tomography and nuclear medicine studies are routinely used for the assessment of renal anatomy and function respectively. Assessment of renal volume and attenuation on CT for diseased kidneys has been shown to allow accurate calculation of differential renal function. We considered whether a simple ellipsoid approximation of renal volume, calculated from 3-axis renal measurements would predict differential renal function in healthy kidneys. METHODS Potential living related donors (LRD) were evaluated with triple-bolus multidetector computed tomography (TB-MDCT) and technetium-99m dimercaptosuccinic acid renography (Tc-99m DMSA). Images were independently assessed by two observers, both blinded to patient demographics and result of DMSA renography. Three dimensional reconstruction was undertaken and images analysed in the sagittal and axial planes. The maximal renal diameter for the long-axis of the kidney in the sagittal plane was obtained (d1). A perpendicular line was drawn from this at the point of maximum anteroposterior depth (d2). The maximum diameter in the coronal plane (d3) was measured on the axial images. An ellipsoid model of the kidney was employed, using the formula; Renal volume= 4/3 x Π x ½d1 x ½d2 x ½d3 The volume of each left and right kidney were summated to give total renal volume. Each renal volume was divided by total renal volume x 100 to give percentage renal volume. The degree of interobserver variability and correlation of ellipsoid volume modelling with DMSA derived DRF was tested with the Pearson correlation coefficient and statistical significance taken as p<0.05. RESULTS 50 patients underwent TB-MDCT and DMSA. All examinations were technically adequate. The correlation of TB-MDCT and DMSA was good with p<0.001 for both left and right renal volumes. Renal volume as measured by two observers correlated closely for both left and right renal volumes (P<0.0001). CONCLUSIONS An ellipsoid approximation of renal volume calculated from renal measurements correlates closely with differential renal function obtained from radionuclide studies. This method is simple and reproducible between observers. Obtaining both anatomical and functional information from a single study saves time and resources whilst exposing the patient to less radiation. © 2011 by American Urological Association Education and Research, Inc.FiguresReferencesRelatedDetails Volume 185Issue 4SApril 2011Page: e888-e889 Advertisement Copyright & Permissions© 2011 by American Urological Association Education and Research, Inc.MetricsAuthor Information John Henderson High Wycombe, United Kingdom More articles by this author Maitham Moslim Damascus, Syrian Arab Republic More articles by this author Matthew Knox Calgary, Canada More articles by this author Nigel Cowan Oxford, United Kingdom More articles by this author Expand All Advertisement Advertisement PDF downloadLoading ...