MRI Functional Evaluation of Children with Renal Dysfunction: First Clinical Experience
Abstract Purpose This survey communicates the first experiences with absolute quantification of the glomerular filtration rate using dynamic contrast-enhanced MRI in children with renal dysfunction. Material and Methods The study included 8 children (5-13 years) who were hospitalized for scientigraphic evaluation, all presenting with congenital urinary or renal disorders. MRI renography was acquired with a clinical MRI system using: 1) a dynamic contrast-enhanced multi-sequence in parallel with an iv bolus of the MRI contrast agent Gd-DTPA (0.05 mM/kg), and 2) MRI volumetry obtained with a morphological multislice sequence covering both kidneys. MRI-GFR was calculated by novel mathematical approaches, based on pixel-wise GFR calculation and measured renal parenchymal volume. Reference-GFR values were found by scientigraphy (gamma emission counting in blood samples withdrawn 0-4 hours following injection of 99mTc-DTPA). Results The table shows calculated values of GFR based on MRI and radioisotope techniques. Two patients failed to successfully undertake the entire examination protocol. In 5 patients, we demonstrated MRI-GFR values comparable to the reference technique (see Table). Conclusions Although differences were observed between MRI and reference methods, this initial experience in children advocates contrast-enhanced MRI as a potential technique for non-invasive measurements of GFR, both on a regional and whole kidney basis. Further patients should be evaluated to reveal whether this approach may become attractive in daily urological or nephrological diagnosis. Table 1 . Patient # GFR MR GFR MR ml/min ml/min 1 103 72 2 93 104 3 106 118 4 87 89 5 75 79 6 97 102