Functional MR urography in children – update 2023

Abstract

Background Functional MR urography (fMRU) has developed into an innovative, radiation-free option for assessing parameters of kidney function in pediatric radiology. The importance of fMRU in comparison to the standardized established nuclear medicine procedure (99mTc-Mercapto-acetyltriglycerine, MAG3 scintigraphy) is shown using SWOT analysis.

Methods To assess the current state of research, a selective literature search was carried out in PubMed. Taking into account the current scientific status, the examination technique, preparation, and evaluation of fMRU are presented.

Results As a result of the comparison with MAG3, fMRU is suitable for certain indications and represents an optimal combination of morphological and functional representation of the kidneys and urinary tract, especially in the case of surgical consequences.

Conclusion fMRU has been successfully established as a diagnostic method for assessing the morphology and function of the kidneys in competition with MAG3 scintigraphy.

Key Points 

• Functional MRU allows reliable statements on the morphology and function of the kidneys and urinary tract.

• The results of the functional assessment of fMRU are comparable to the results of MAG3 scintigraphy.

• The complex implementation and demanding evaluation limits the spread of fMRU as a complete alternative to MAG3 scintigraphy. fMRU is reserved for special indications.

• Functional MRU has prevailed over MAG3 scintigraphy for complex renal and urinary tract anomalies (CAKUT) that require surgical correction. An example is the clarification of dribbling in girls, which is usually based on an ectopic opening of a ureter in a double system.

Citation Format

• Kirsch H, Krüger P, John-Kroegel U et al. Functional MR urography in children – update 2023. Fortschr Röntgenstr 2023; 195: 1097 – 1105

Key words

functional MR urography - congenital anomalies of the kidney and urinary tract - glomerular filtration rate - children, adolescents - kidney - renal function

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