OC127: Increased nuchal translucency and distended jugular lymphatic sacs by first‐trimester ultrasound

Abstract

Morphological data revealed that nuchal edema is associated with jugular lymphatic distension. The objective of this study was to investigate the presence and volume of jugular lymphatic sacs (JLS) in first-trimester fetuses with normal and increased nuchal translucency (NT). In this prospective study 26 fetuses with NT > 95th percentile were compared to 137 fetuses with normal NT. Follow up was complete. After crown-rump length and NT measurement the neck region of the fetus was studied by transvaginal ultrasound. The JLS presented as spheroid translucencies in the antero-lateral region of the neck. The volume of the JLS was calculated using the formula of a spheroid: length * height * width * 3/4 phi. The incidence of JLS significantly differed between fetuses with enlarged NT and control group (p < 0.0001). In the group of 26 fetuses with increased NT 22 fetuses (85%) had clearly visible JLS. Chorion villus sampling revealed aneuploidy in 10 and euploidy in 16 fetuses. In the control group 2 fetuses (1.5%) showed JLS. Both had a NT of 2.8, 2.9 respectively and a normal outcome at birth. Logistic regression analysis in the total population showed that increased NT was significantly associated with the presence of JLS (OR 9.48, CI 2.93–30.75). In the fetuses with present JLS an increment of crown-rump length was significantly correlated with enlargement of the volume of the right sac (r = 0.51; P = 0.01). The left sac showed the same association. However, significance was not reached (r = 0.40, p = 0.09). An enhancement of the NT did not show a significant relation with enlargement of the volume of the JLS. Enlarged nuchal translucency is highly associated with jugular lymphatic sacs on first-trimester ultrasound. In our opinion the pathophysiology of the increased NT can be explained by a disturbed lymphangiogenesis. This disturbance is present in both chromosomally normal and abnormal fetuses.