Reference values for the length and area of the fetal corpus callosum on 3-dimensional sonography using the transfrontal view.
OBJECTIVE
The purpose of this study was to determine reference values for the length and area of the fetal corpus callosum between 20 and 33 weeks' gestation using 3-dimensional sonography.


METHODS
A cross-sectional study was performed in 293 healthy pregnant women between 20 and 33 weeks' gestation. The length and area of the corpus callosum were obtained via the transfontal view with the metopic suture as an acoustic window using 3-dimensional sonographic aquisitions. Linear and weighted polynomial regression models were used, which were adjusted by residual analysis and the R(2) determination coefficient. Intraobserver and interobserver reproducibilities were analyzed by an intraclass correlation coefficient.


RESULTS
The mean corpus callosum length ± SD varied from 19.52 ± 2.24 to 40.36 ± 2.87 mm, whereas the mean area varied from 0.44 ± 0.11 to 1.47 ± 0.21 cm(2) at 20 and 33 weeks, respectively. The length and area were highly correlated with gestational age: corpus callosum length = -52.41 + 4.71 × gestational age - 0.06 × gestational age(2) (R(2) = 0.868); and corpus callosum area = -2.47 + 0.16 × gestational age - 0.000037 × gestational age(2) (R(2) = 0.765). The intraobserver and interobserver reproducibilities were excellent, with intraclass correlation coefficients of 0.98 and 0.94 for the length and 0.99 and 0.90 for the area, respectively.


CONCLUSIONS
Reference values for the length and the area of the fetal corpus callosum between 20 and 33 weeks' gestation were determined with high reproducibility.
Department of Obstetrics, Federal University of São Paulo, Rua Carlos Weber 956, Apartamento 113 Visage, Alto da Lapa, 05303-000 São Paulo-SP, Brazil. araujojred@terra.com.br
Edward
E
Araujo Júnior
Milena
M
Visentainer
Christiane
C
Simioni
Rodrigo
R
Ruano
Luciano Marcondes Machado
LM
Nardozza
Antonio Fernandes
AF
Moron
D000328:Adult; D003337:Corpus Callosum / Q000000981:diagnostic imaging* / Q000196:embryology; D003430:Cross-Sectional Studies; D005260:Female; D005865:Gestational Age; D006801:Humans; D021621:Imaging, Three-Dimensional; D011247:Pregnancy; D012016:Reference Values; D012044:Regression Analysis; D015203:Reproducibility of Results; D016216:Ultrasonography, Prenatal / Q000379:methods*