The role of magnetic resonance imaging (MRI) in refining the diagnosis of suspected fetal renal anomalies

ObjectiveTo detect the role of magnetic resonance imaging in refining the diagnosis of suspected fetal renal anomalies detected during screening sonography.Methods54 pregnant women, with suspected fetal renal anomalies detected during routine ultrasound screening, were rescanned by MRI to refine the diagnosis of the suspected renal anomalies. The pregnancy outcome was examined externally and by postnatal ultrasonography.Results54 cases of suspected renal anomalies detected during screening sonography of 8 400 pregnant women (0.6%), were rescanned by MRI in this study. The MRI diagnosed, 29 (53.7%) cases of parenchymal renal disease, 20 (37.0%) cases of hydronephrosis, 3 (5.6%) cases of single renal cyst and 2 (3.7%) cases of megacystis + hydroureter. The amniotic fluid volume was normal in 33 (61.0%) cases, while it was decreased in 21 (39.0%) cases. Two cases of chromosomal aberration (3.7%) were detected in the studied cases. During antenatal follow up of the prenatal diagnosed cases with renal anomalies 2 cases of bilateral RA (Potter's syndrome died in utero = IUFD) and out of 52 live births 1 case of NND occurred due to bilateral MCKD with trisomy 18. In this study, when the prenatal findings were compared with the postnatal findings, the MRI was 89.5% accurate, while the prenatal ultrasound was 85% accurate in diagnosing fetal renal anomalies.ConclusionThe MRI can be used as a complementary adjunctive modality with excellent tissue contrast especially in equivocal cases or inconclusive sonographic findings.