Measurement of Renal Dimensions to Determine Standard Reference Renal Volume Model for Clinical Application in Ghana

Abstract

The study is based on measurements of renal dimensions to determine standard reference renal volume model and renal volumetric ellipsoid coefficient. Two methods, Voxel count method and rotational renal ellipsoid equation were the two measuring tools used with an integrated MVL application software platform. The procedure involve measurement of linear dimensions together with using the snake technique to draw the region of interest (ROI) for the volumetric measurements. These were done to obtain: renal length, lateral diameter, A-P diameter and the total number of voxels to estimates the renal volume. These parameters were used to calculate renal volume using the rotational renal ellipsoid equation as well as using the Minitab statistical software to model renal volume equation. The reference standard renal volume was also determined using water displacement with the Archimedes' principle. The average renal shape index and its dispersion (i.e. covariance matrix) was approximately 1±0.02. The male average measured values for right and left kidneys were as follows: renal length, 103.35cm and 105.13cm, lateral diameter, 60.79 and 60.40 and A-P diameter, 44.12 and 44.95 and renal volume; 146.74cm3 and 151.76cm3 respectively. Furthermore, the female average measured values for right and left kidneys were as follows: renal length, 101.43 and 102.98, lateral diameter, 59.20 and 59.02 and A-P diameter, 43.09 and 44.82, renal volume 142.04cm3 and 148.29cm3 respectively. The average estimated renal volumetric ellipsoid coefficient (VeC) was 0.53. However, various variations for both male and female, with their corresponding right and left kidneys were, 0.5283, 0.5297, 0.5280 and 0.5304 respectively. The reference renal dimensions including the standard renal volume and renal volumetric ellipsoid coefficient are recommended for clinical application in Ghana.