Micro-CT Imaging of Tracheal Development in Down Syndrome and Non-Down Syndrome Fetuses

OBJECTIVES

Down syndrome (DS) is associated with airway abnormalities including a narrowed trachea. It is uncertain whether this narrowed trachea in DS is a consequence of deviant fetal development or an acquired disorder following endotracheal intubation after birth. This study aimed to compare the tracheal morphology in DS and non-DS fetuses using microfocus computed tomography (micro-CT).

METHODS

Twenty fetal samples were obtained from the Dutch Fetal Biobank and divided into groups based on gestational age. Micro-CT images were processed to analyze tracheal length, volume, and cross-sectional area (CSA).

RESULTS

Mean tracheal length and tracheal volume were similar in DS and non-DS fetuses for all gestational age groups. Mean, minimum, and maximal tracheal CSA were statistically significantly increased in the single DS fetus in the group of 21-24 weeks of gestation, but not in other gestational age groups. In 90% of all studied fetuses, the minimum tracheal CSA was located in the middle third of the trachea.

CONCLUSION

Tracheal development in DS fetuses was similar to non-DS fetuses between 13 and 21 weeks of gestation. This suggests that the narrowed tracheal diameter in DS children may occur later in fetal development or results from postnatal intubation trauma. The narrowest part of the trachea is in majority of DS and non-DS fetuses the middle third.

LEVEL OF EVIDENCE

Level 3 Laryngoscope, 2024.

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