Gestational age-specific MRI reference values for fetal renal morphology and ADC

Area of Science:

• Radiology
• Fetal Medicine
• Medical Imaging

Background:

• Fetal renal developmental abnormalities are common congenital malformations.
• These abnormalities are linked to adverse perinatal outcomes.
• Fetal MRI offers valuable morphological and quantitative data, but gestational age-specific reference values are limited.

Purpose of the Study:

• To establish MRI-based reference values for normal fetal renal morphology.
• To determine gestational age-specific reference values for apparent diffusion coefficient (ADC) in fetal kidneys.
• To create quantitative benchmarks for fetal renal MRI assessment.

Main Methods:

• Retrospective observational study of 313 singleton pregnancies (23-38 weeks GA).
• 1.5T fetal MRI including T2-weighted and diffusion-weighted imaging.
• Measurement of renal diameters, mean renal parenchymal thickness (MRPT), T2 relative signal intensity (RSI-T2), and apparent diffusion coefficient (ADC).

Main Results:

• Good to excellent inter-observer reproducibility for all measured parameters.
• Renal diameters and MRPT significantly increased with gestational age (GA).
• Renal ADC values showed significant negative correlations with GA, with established regression equations.

Conclusions:

• The study provides gestational age-stratified reference ranges for fetal kidney MRI parameters.
• These quantitative benchmarks are valuable for assessing normal fetal kidney development.
• The findings support improved fetal renal MRI assessment and future studies on abnormalities.