The relationship between the fetal volume-corrected renal artery pulsatility index and amniotic fluid volume

Viola Seravalli, Jena L. Miller, Dana Block-Abraham, Cyrethia Mcshane, Sarah Millard, Ahmet Baschat

Research output: Contribution to journalArticle


Introduction: To evaluate if the volume-corrected renal artery pulsatility index (vcRA-PI) is more closely related to the amniotic fluid level than the uncorrected or the gestational age (GA)-adjusted RA-PI. Methods: RA-PI and kidney volume were measured in low-and high-risk pregnancies at 17-38 weeks. Fetal anomalies associated with nonrenal causes of abnormal amniotic fluid volume were excluded. The vcRA-PI was calculated by dividing the RA-PI by the renal volume. The RA-PI was adjusted for GA, to obtain the GA-adjusted RA-PI. The uncorrected, GA-adjusted, and the vcRA-PI were related to the amniotic fluid level using nonparametric tests and receiver operating characteristic (ROC) curve analyses. Results: 146 examinations from 59 pregnancies were reviewed. Of these, 16 had oligo-and 15 had polyhydramnios. A higher vcRA-PI was associated with oligohydramnios (OR 2.54, 95% CI 1.67-3.86, p < 0.001), while the uncorrected RA-PI and GA-adjusted RA-PI were not able to predict oligohydramnios. ROC curve analysis showed a high predictive accuracy of the vcRA-PI for oligohydramnios (AUC 0.84, 95% CI 0.72-0.94). On the other hand, the uncorrected RA-PI and GA-adjusted RA-PI significantly predicted polyhydramnios (p = 0.04 and 0.02, respectively), while the vcRA-PI did not. Conclusion: The vcRA-PI is superior to the uncorrected and the GA-adjusted RA-PI in predicting oligohydramnios.

Original languageEnglish (US)
Pages (from-to)97-102
Number of pages6
JournalFetal Diagnosis and Therapy
Issue number2
StatePublished - Aug 1 2019



  • Amniotic fluid
  • Doppler ultrasound
  • Fetal kidney
  • Oligohydramnios
  • Renal artery

ASJC Scopus subject areas

  • Pediatrics, Perinatology, and Child Health
  • Embryology
  • Radiology Nuclear Medicine and imaging
  • Obstetrics and Gynecology

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