TY - JOUR
T1 - A simple method to estimate renal volume from computed tomography
AU - Breau, Rodney H.
AU - Clark, Edward
AU - Bruner, Bryan
AU - Cervini, Patrick
AU - Atwell, Thomas
AU - Knoll, Greg
AU - Leibovich, Bradley C.
PY - 2013
Y1 - 2013
N2 - Introduction: Renal parenchymal volume can be used clinically to estimate differential renal function. Unfortunately, conventional methods to determine renal volume from computed tomography (CT) are time-consuming or difficult due to software limitations. We evaluated the accuracy of simple renal measurements to estimate renal volume as compared with estimates made using specialized CT volumetric software. Methods: We reviewed 28 patients with contrast-enhanced abdominal CT. Using a standardized technique, one urologist and one urology resident independently measured renal length, lateral diameter and anterior-posterior diameter. Using the ellipsoid method, the products of the linear measurements were compared to 3D volume measurements made by a radiologist using specialized volumetric software. Results: Linear kidney measurements were highly consistent between the urologist and the urology resident (intraclass correlation coefficients: 0.97 for length, 0.96 for lateral diameter, and 0.90 for anterior-posterior diameter). Average renal volume was 170 (SD: 36) cm3 using the ellipsoid method compared with 186 (SD 37) cm3 using volumetric software, for a mean absolute bias of -15.2 (SD 15.0) cm3 and a relative volume bias of -8.2% (p < 0.001). Thirty-one of 56 (55.3%) estimated volumes were within 10% of the 3D measured volume and 54 of 56 (96.4%) were within 30%. Conclusion: Renal volume can be easily approximated from contrast- enhanced CT scans using the ellipsoid method. These findings may obviate the need for 3D volumetric software analysis in certain cases. Prospective validation is warranted.
AB - Introduction: Renal parenchymal volume can be used clinically to estimate differential renal function. Unfortunately, conventional methods to determine renal volume from computed tomography (CT) are time-consuming or difficult due to software limitations. We evaluated the accuracy of simple renal measurements to estimate renal volume as compared with estimates made using specialized CT volumetric software. Methods: We reviewed 28 patients with contrast-enhanced abdominal CT. Using a standardized technique, one urologist and one urology resident independently measured renal length, lateral diameter and anterior-posterior diameter. Using the ellipsoid method, the products of the linear measurements were compared to 3D volume measurements made by a radiologist using specialized volumetric software. Results: Linear kidney measurements were highly consistent between the urologist and the urology resident (intraclass correlation coefficients: 0.97 for length, 0.96 for lateral diameter, and 0.90 for anterior-posterior diameter). Average renal volume was 170 (SD: 36) cm3 using the ellipsoid method compared with 186 (SD 37) cm3 using volumetric software, for a mean absolute bias of -15.2 (SD 15.0) cm3 and a relative volume bias of -8.2% (p < 0.001). Thirty-one of 56 (55.3%) estimated volumes were within 10% of the 3D measured volume and 54 of 56 (96.4%) were within 30%. Conclusion: Renal volume can be easily approximated from contrast- enhanced CT scans using the ellipsoid method. These findings may obviate the need for 3D volumetric software analysis in certain cases. Prospective validation is warranted.
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U2 - 10.5489/cuaj.1338
DO - 10.5489/cuaj.1338
M3 - Article
AN - SCOPUS:84894058263
SN - 1911-6470
VL - 7
SP - 189
EP - 192
JO - Journal of the Canadian Urological Association
JF - Journal of the Canadian Urological Association
IS - 5-6 JUN
ER -