Three-dimensional sonographic volume measurement of the fetal spleen

Aim: The objective of this longitudinal study was to evaluate the growth of the fetal spleen in normal pregnancies, using three-dimensional ultrasound. Methods: Three-dimensional sonographic examinations were performed on 14 appropriate-for-gestational-age fetuses. Fetal splenic volume was measured every 2-3 weeks after 20 weeks of gestational age until delivery. Results: Curvilinear relationships were found between the gestational age and splenic volume (R-2 = 80.2%, P < 0.0001), and normal ranges of splenic volume measurements for estimating the growth of the fetal spleen during normal pregnancy were generated. We found that the splenic volume calculation based on the equation for the volume of the ellipsoid by conventional two-dimensional ultrasound in previous investigations is about twice as large as that using three-dimensional ultrasound in our study, whereas the present data described in this study is quite comparable with previous data from an autopsy series. Conclusion: Our findings suggest that the standard curve for the fetal splenic volume using three-dimensional ultrasound provides a superior means for evaluating the normal splenic growth in the fetus and for identifying splenic abnormalities in utero. However, the data and its interpretation in our study should be taken with some degree of caution because of the small number of subjects studied. Further studies involving a larger sample size would be needed to confirm these findings.