2D Shear wave elastography for evaluation of renal cortex and medulla: stiffness values in healthy children

PurposeTo evaluate renal cortical and medullary stiffness using 2D Shear-wave elastography (SWE) in healthy children.MethodsIn this IRB approved prospective study, we measured the stiffness of cortex and medulla of children (4 months-17 years) at the upper pole, mid pole, and lower pole in bilateral kidneys.ResultsThe median (IQR) values of renal cortex in <1 year age group was 8.7 (5.7-11.7) kPa for right and 8.7 (4.2-14.1) kPa for the left side. For 1-5 years age group, it was 7.3 (5.3-10) kPa for the right and 8.9 (6-12.3) kPa for the left side. For >5 years, it was 7.4 (5.3-11.2) kPa for the right and 9.6 (6.2-12.7) kPa for the left side. The median (IQR) values of renal medulla in <1 year age group was 7.1 (5.1-12.5) kPa for right and 6.8 (4-10.6) kPa for the left side. For 1-5 years age group, it was 7.2 (4.9-9.7) kPa for the right and 6.9 (5.6-9.9) kPa for the left side. For >5 years, it was 6.8 (5.1-9.6) kPa for the right and 7 (5-10.2) kPa for the left side. The differences in the elasticity values amongst these groups were statistically insignificant (p>0.05). There was a significant correlation between SWE values of cortex and medulla of right kidney (& rho;=0.64) and of left kidney (& rho;=0.61), respectively.ConclusionSWE values of renal cortical and medullary stiffness in healthy children do not correlate with age. There is a significant correlation between SWE values of cortex and medulla of the kidneys in healthy children.