Correlation of prenatal renal parenchymal thickness with postnatal outcome of fetal hydronephrosis

Purpose: The aims of this research are to correlate prenatal renal parenchymal thickness with postnatal outcome of fetal hydronephrosis, to establish the predictability of prenatal renal parenchymal thickness for surgical treatment and to apply this parameter to the evaluation and the follow-up of prenatal hydronephrosis. Material and Method: Between Jun 1991 and Jun 1998 we retrospectively identified 59 cases of fetal hydronephrosis in which renal pelvic anteroposterior diameter(PAPD) was greater than 10mm. Renal parenchymal thickness(RPT), renal pelvis anteroposterior diameter and renal anteroposterior diameter(RAPD) were measured on midtransverse from prenatal sonograms. The ability of these parameters to predict who would require surgical treatment was examined. The difference of these parameters in groups were compared using Wilcoxon rank sums analysis. Results: 66.7% of fetuses with a renal parenchymal thickness lesser than 8mm and 71.4% of fetuses with a renal parenchymal thickness lesser than 6mm required surgical treatment. 33.3% of fetuses with an PAPD greater than 12mm and 45% of fetuses with an PAPD greater than 15mm required surgical treatment. 60% of fetuses with an ratio of PAPD/RAPD greater than 0.4 and 70% of fetuses with an ratio of PAPD/RAPD greater than 0.5 required surgical treatment. Conclusion: The research shows that RPT could be used as an useful parameter in the prediction of requirement of postnatal surgical treatment of fetal hydronephrosis ,in addition to the size of PAPD and the ratio of PAPD/RAPD which have been assumed as one of the most important parametersrestrictio