Reference range for the fetal intracranial translucency measurement between 11 and 14?+?2 weeks of gestation in a Brazilian population.

The journal of maternal-fetal & neonatal medicine : the official journal of the European Association of Perinatal Medicine, the Federation of Asia and Oceania Perinatal Societies, the International Society of Perinatal Obstetricians

PubMedID: 26400724

Peixoto AB, Caldas TM, Lasmar LA, Martins WP, Pares DB, Araujo Júnior E. Reference range for the fetal intracranial translucency measurement between 11 and 14?+?2 weeks of gestation in a Brazilian population. J Matern Fetal Neonatal Med. 2016;1-15.
OBJECTIVE
To establish a reference range for the fetal intracranial translucency (IT) measurement between 11 and 14?+?2 weeks in a Brazilian population.

METHODS
A retrospective cross-sectional study was performed with 199 low-risk singleton pregnancies during the first trimester ultrasound exam. The IT (fourth ventricle width) measurement was performed in a mid-sagittal view of fetal profile defined by two echogenic borders - the dorsal part of the brain stem anteriorly and the choroid plexus of the fourth ventricle posteriorly. Polynomial regression was used to obtain the best fit using fetal IT measurements and crown-rump length (CRL). Percentiles 5th, 50th and 95th were determined for each gestational age.

RESULTS
The mean of fetal IT ranged from 1.6 mm at CRL 45 to 2.0 mm at CRL 84 mm. A best fit curve was a first-degree polynomial regression: IT measurement?=?1.001?+?0.0124?×?CRL (R(2)=0.09).

CONCLUSION
Reference range for the fetal IT measurement between 11 and 14?+?2 weeks of gestation in a Brazilian population was established.