Fetal Weight Estimation and Organ Volume Measurement by Three-Dimensional Ultrasonography
Pp. 177-191 (15)
With great advancement in medical imaging methods, it is possible to measure the volume of fetal
organs and structures. Two principal techniques have been described, the ‘parallel technique’ and the ‘rotational
method’, but the latest one is more used over the world in clinical practice because of being easier and faster as
well as allowing corrections on the multiplanar imaging. Recent studies have been using 3DUS in order to
incorporate the soft-tissue thickness into the mathematical formulas to estimate fetal weight. A few equations have
been reported which are present in this present chapter. 3DUS can also be applied for estimating fetal organ
volumes. Fetal lung volumes can be useful for the prediction of pulmonary hypoplasia in thoracic malformations,
while fetal heart volume for fetal heart function. To assess the status of fetal growth and nutrition, fetal liver has
been proposed. Fetal renal volumes may be an interesting tool for the monitoring of renal conditions, including
nephromegaly, hypoplasia and hydronephrosis. Fetal adrenal gland volumes could be of interest to evaluate
adrenal tumors and to predict labor, since adrenal hormonal changes are implicated in triggering labor. Fetal brain
volumes are also suggested to provide an insight into the nature of abnormal fetal growth. In conclusion, 3DUS
can be indicated to improve the prediction of fetal organ dysfunction and weight disturbances.
Obstetrics Department, Faculty of Medicine of the University of Sao Paulo, Sao Paulo, Brazil.