Objective: To compare fetal upper arm and thigh volume measurements acquired by three-dimensional (3D) ultrasound using the multiplanar and the eXtended Imaging Virtual Organ Computer-aided AnaLysis (XI VOCAL) methods with different number of sectional planes.
Methods: This study enrolled 40 healthy pregnant women between 20 and 40 weeks of gestation. The volume of fetal limbs was calculated using the multiplanar (with 5.0 mm intervals) and the XI VOCAL (with 5, 10, 15, and 20 slice planes) methods. Comparison between the techniques was made by analysis of variance and Bonferroni statistical tests.
Results: Mean fetal upper arm volume measured by the 15 sectional planes XI VOCAL method was lower than the same method using 5 and 10 planes instead (p = 0.025 and 0.039, respectively). Fetal thigh volume showed no statistically significant differences among all studied methods.
Conclusion: The XI VOCAL using 15 sectional planes method underestimated the fetal upper arm volume by 5 and 10 planes XI VOCAL techniques.