[Ultrasonographic determination of amniotic fluid--comparison of two methods].

Abstract

A study was performed in order to find a suitable ultrasonographic method of determining amniotic fluid volumes. Volumes were measured in 398 gravidae with no fetal or maternal pathology. The Depot V method described by Chamberlain et al. and Phelan et al.'s four-quadrant method were used to perform the measurements. Normal-value curves were prepared from the results. The reproducibility of the two methods was also verified. The results of the study showed that the normal-value curve derived from the four-quadrant method was in very good agreement with the results of the quantitative indicator dilution methods described by Queenan et al., which also indicated a marked decrease in volume after GW 34. It may be concluded from this that the four-quadrant method produces representative figures for the actual volume of amniotic fluid. A further distinctive feature of the four-quadrant methods is its very good reproducibility. The decrease in the fluid volume towards the end of gestation could not be demonstrated by the Depot V method. The four-quadrant method may therefore be regarded as a suitable semi-quantitative ultrasonographic method of determining the amniotic fluid volume.