Valoración de la translucencia nucal y anatomía fetal en la ecografía de 11-13+6 semanas: técnica bidimensional frente a tridimensional

Abstract

IntroductionAn evaluation is made of the possibility of assessing foetal anatomy and measuring nuchal translucency (NT) from the deferred study of the volume captured using three-dimensional (3D) ultrasound. ObjectiveTo compare the results obtained by the two-dimensional (2D) and 3D ultrasound examination. MethodA prospective study performed on 100 single pregnancies, who came for aneuploidy screening between 11-13.6 weeks gestation. A 2D abdominal ultrasound was performed by a first examiner (E1), with an anatomical study (defined based on an anatomy score), an NT evaluation (based on criteria of the Foetal Medicine Foundation) and a colour Doppler map (ductus venosus and umbilical vessels. The same examiner (E1) captured a total foetal volume by abdominal 3D, with and without colour Doppler. The 3D volumes were assessed by two examiners (E1 and E2) in deferred mode using multiplanar navigation. ResultsMeasurement of the crown-rump length (CRL) could be made in 2D and 3D by both examiners in 100% of cases, with no significant differences between them. The NT could be assessed in 100% of cases using 2D ultrasound, and in 63% and 48% of cases using 3D ultrasound by E1 and E2, respectively. The anatomy assessment percentages were lower with 3D, although they reached 90-100% in structures such as the head, thorax, abdomen, stomach and limbs. There were no differences in the examination times between the techniques. It showed that the more experienced the examiner, the lower the time of deferred analysis; although this time was established from 20 volumes analysed (learning curve). ConclusionThe obtaining a single total foetal volume by trans-abdominal 3D ultrasound between 11-13.6 weeks allows an assessment to be made of the basic anatomy and the NT, although in percentages lower than in 2D.