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Updated: Jun 16, 2026
A Novel Use of Three-dimensional High-frequency Ultrasonography for Early Pregnancy Characterization in the Mouse
Published on: October 24, 2017
Comparison of gestational sac volume by 3D-sonography using planimetric, virtual organ computer-aided analysis and
Luciano Marcondes Machado Nardozza1, Liliam Cristine Rolo, Edward Araujo Júnior
1Department of Obstetrics, São Paulo Federal University , São Paulo, SP, Brazil.
Objective:
To compare different three-dimensional (3D) methods in the assessment of gestational sac volume (GSV).
Design:
Cross-sectional study involving 74 normal pregnancies between 7 and 11 weeks.
Setting:
Department of Obstetrics, São Paulo Federal University (UNIFESP).
Methods:
GSV was measured through 3D ultrasound using the planimetric, virtual organ computer-aided analysis (VOCAL) and extended imaging virtual organ computer-aided analysis (XI VOCAL) methods. The planimetric method used a sequence of adjacent planes that are 3 mm thick. For the VOCAL methods, six adjacent planes and a 30 degrees rotation were used. A total of 15 adjacent planes were used for the XI VOCAL method. Regression models with a determination coefficient (R(2)) were created to assess the correlation between GSV and gestational age (GA). Intraclass correlation coefficient (ICC) and Bland-Altman graphs were used to assess the correlation between the three methods and ANOVA was used to compare means.
Results:
All three methods showed a correlation between GSV and GA (R(2) = 0.65 for XI VOCAL, R(2) = 0.65 for planimetric and R(2) = 0.66 for VOCAL). There was a strong correlation between the three methods (XI VOCAL vs. planimetric ICC = 0.995; XI VOCAL vs. VOCAL ICC = 0.998 and planimetric vs. VOCAL ICC = 0.995) without any significant differences according to the Bland-Altman graphs or ANOVA (p < 0.002).
Conclusions:
The three 3D ultrasound methods used for GSV assessment between 7 and 11 weeks are concordant. These methods can be used interchangeably during the first trimester of pregnancy to measure GSV.
