Isolated Tortuous Ductus Arteriosus in a Fetus: HDlive Flow with Spatiotemporal Image Correlation (STIC) Study.

Objectives To describe prevalence, outcome, color Doppler, and HDlive Flow (Silhouette) with spatiotemporal image correlation (STIC) features of isolated tortuous ductus arteriosus in Japanese fetuses at 28-31 + 6 weeks of gestation.Methods During a 37-month period, 3,150 fetal screenings were performed at 28-31 + 6 weeks of gestation. Isolated tortuous ductus arteriosus was evaluated using color Doppler and HDlive Flow (Silhouette) with STIC. Prevalence and outcomes were also assessed.Results There were 22/3,150 fetuses (0.7%) had isolated tortuous ductus arteriosus at 28-31 + 6 weeks of gestation. According to color Doppler and HDlive Flow findings, two types of isolated tortuous ductus arteriosus (Right-angled and Loop shapes) were classified. There were 20 Right-angled and 2 Loop shapes. One fetus with a Right-angled shape was associated with aortic tortuosity. HDlive Flow with STIC revealed spatial relationships of tortuous ductus arteriosus, aortic arch, and descending aorta. All fetuses with isolated tortuous ductus arteriosus had good neonatal outcomes.Conclusions The incidence of isolated tortuous ductus arteriosus in Japanese fetuses was low compared with those in previous reports. HDlive Flow with STIC provides precise information for spatial recognition and differentiation of isolated tortuous ductus arteriosus, resulting in two type classifications. Isolated tortuous ductus arteriosus in a fetus may be a transient, benign finding in utero.