Prenatal diagnosis of urinary tract abnormalities.

BACKGROUND

To compare magnetic resonance imaging with ultrasonography for the diagnosis of urinary tract abnormalities.

METHODS

Two cases of multicystic dysplastic kidney, six cases of ureteropelvic junction obstruction, and one case of autosomal recessive polycystic kidney disease were diagnosed on antenatal ultrasonography and/or magnetic resonance imaging.

RESULTS

In case of multicystic dysplastic kidney and ureteropelvic junction obstruction, ultrasonography showed characteristic features of their diseases. Magnetic resonance imaging was insufficient to diagnose these diseases. In a case of autosomal recessive polycystic kidney disease, ultrasonography and magnetic resonance imaging were both useful to show characteristic features of this disease, and thus made it possible to make a correct diagnosis of the disease.

CONCLUSIONS

For a prenatal fetal diagnosis, it is necessary to observe both fetal anatomy and an evolution of the fetal abnormality. The above mentioned three types of urinary tract abnormalities changed their anatomic configurations and/or texture of urinary tracts as the pregnancies progressed. To observe these changes, the usefulness of ultrasonography is superior to that of magnetic resonance imaging for the present. Although ultrasonography and magnetic resonance imaging show fetal urinary tract abnormalities, these instruments should be used properly during the period of the pregnancy on case-by-case bases.