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Published on: August 2, 2017
Correlation of ultrasound estimated with dye-determined or directly measured amniotic fluid volume revisited
Everett F Magann1, Songthip Ounpraseuth, Suneet P Chauhan
1Department of Obstetrics and Gynecology, University of Arkansas for Medical Sciences, Little Rock, Ark., USA.
Background/Aims:
To examine the relationship of the amniotic fluid index (AFI) and single deepest pocket (SDP) with an AFV as modelled by Brace or Magann.
Methods:
AFI and SDP were evaluated for their correlation with an actual AFV using the Spearman correlation coefficient.
Results:
482 AFI and 468 SDP pregnancies were evaluated. There was a significant association between the AFI and SDP and an actual AFV (p < 0.0001). The AFI range of 5.1-20 was better correlated than 5.1-24 for normal AFVs Brace (κ = 0.175) and Magann (κ = 0.356) versus 5.1-24 (κ = 0.150 and κ = 0.319), respectively. The agreement level t for the AFI (κ = 0.175) and SDP (κ = 0.126) using Brace was slight and for the AFI (κ = 0.356) and SDP (κ = 0.295) using Magann was fair.
Conclusions:
Both the AFI and SDP were correlated with actual AFV using both models. AFI of 5.1-20 better categorizes normal volumes. Although the Magann model correlates AFI/SDP and AFV better, the superiority is minimal.
