Age dependence of the renal apparent diffusion coefficient in children

Abstract

Background: Diffusion imaging has proved to be a powerful tool for diagnosing ischemic lesions in the brain, and the technique is now being applied to other organs, including the kidneys. For quantitative studies it is important to define the normal values of the apparent diffusion coefficient (ADC), given the important physiological changes that occur in the kidney during early childhood it is likely that the ADC changes markedly during this period. OBJECTIVE. To evaluate the age dependent changes in the ADC of normal kidneys in the pediatric population.

Materials and methods: The whole kidney ADC was calculated for 62 pediatric patients on a 1.5-T system using a respiratory-triggered, single-shot diffusion tensor imaging sequence with b values of 50, 200, and 350 mm(2)/s. RESULTS. The ADC was found to increase with age with the largest increase being in the first year of life, the rate of change being described by a constant plus a power function, specifically 1349+[358.5*[age 0.34]], ( P<0.001).

Conclusion: The renal ADC changes significantly during childhood.