A Novel Approach to Prenatal Measurement of the Fetal Frontal Lobe Using Three-Dimensional Sonography.

Abstract

Objective: To assess the feasibility of a standardized approach to biometric measurement of the fetal frontal lobe and to construct frontal lobe growth trajectories throughout gestation.

Study design: A sonographic 3-dimensional (3D) volume set was obtained and measured in 101 patients between 16.1 and 33.7 gestational weeks. Measurements were obtained by 2 independent raters. To model the relationship between gestational age and each frontal lobe measurement, flexible linear regression models were fit using penalized regression splines.

Results: The sample contained an ethnically diverse population (7.9% Native Americans, 45.5% Hispanics/Latinas). There was high interrater reliability (correlation coefficients 0.95, 1.0, and 0.87 for frontal lobe length, width, and height; p values <0.001). Graphs of the growth trajectories and corresponding percentiles were estimated as a function of gestational age. The estimated rates of frontal lobe growth were 0.096 cm/week, 0.247 cm/week, and 0.111 cm/week for length, width, and height, respectively.

Conclusion: To our knowledge, this is the first study to examine fetal frontal lobe growth trajectories through 3D prenatal ultrasound examination. Such normative data will allow for future prenatal evaluation of a particular disease state by 3D ultrasound imaging.