A new method of color Doppler perfusion measurement via dynamic sonographic signal quantification in renal parenchyma

Perfusion quantification of tissues is an important goal to evaluate the state of blood supply of an organ. We developed a method to quantify tissue perfusion via color Doppler signal quantification from sonographic videos and applied this to describe renal parenchymal perfusion in healthy kidneys.

Color Doppler sonographic videos of renal perfusion from both kidneys of 87 healthy children (age 2 weeks to 16 years) were recorded under defined conditions. Perfusion data (color hue, color area) were measured in a standardized region of interest automatically. Signal intensity was calculated as whole ROIs (regions of interest) mean flow velocity (cm/s) encoded by color Doppler signals during one full heart cycle.

Normal signal intensity values are: 1.86 cm/s in the region encompassing central 50% of the renal cortex and 0.56 cm/s in the peripheral 50% of the renal cortex. These differences are significant. Signal intensity of both kidneys did not differ.

Signal intensity of cortical tissue in healthy kidneys was quantified noninvasively from color Doppler signal data in an easily accomplishable manner with new measurement software. Normal values for this technique have been calculated. Possible further applications might be all situations, where perfusion changes could be expected like inflammation, renal insufficiency, vascular diseases and tumors.