Jugular vein and carotid artery blood flow in fetuses with increased nuchal translucency at 10-14 weeks' gestation.
OBJECTIVE
The aim of our study was to obtain measurements of the jugular vein and carotid artery pulsatility index (PI) at 10-14 weeks' gestation in chromosomally normal and abnormal fetuses with or without increased nuchal translucency (NT), in order to explore whether a relationship exists between increased NT and overperfusion of the head.


METHODS
This was a prospective study involving 179 pregnant women at high risk for chromosomal anomalies or structural malformations who were referred for chorionic villus sampling or first-trimester ultrasound examination at 10-14 weeks' gestation, respectively. Color and pulsed Doppler ultrasound were used to obtain jugular vein and carotid artery blood flow velocity waveforms at the level of the mid-neck. All Doppler measurements were obtained by a single investigator. The PIs of the jugular vein and carotid artery were correlated with NT measurement and fetal karyotype.


RESULTS
Doppler measurements of the jugular vein and carotid artery were successfully obtained in 90.5% of the fetuses. The fetal karyotype was abnormal in 13 cases, including three trisomies 21 and two trisomies 18, and normal in 149 cases. In the group with normal karyotype the NT was above the 95th percentile in 22 cases (15%). No correlation between the jugular vein or the carotid artery PI and the thickness of the NT was found. There were no significant differences when comparing the values of the jugular vein and carotid artery PI between the group with normal NT and the group with increased NT, or between the group with a normal karyotype and an abnormal karyotype.


CONCLUSIONS
Our results suggest that NT is not related to blood flow impedance in either the carotid artery or the jugular vein. Overperfusion and venous congestion of the head do not appear to be a causative pathophysiological mechanism involved in increased NT.
Martínez
J M
JM
Department of Obstetrics and Gynaecology, ICGON, Hospital Clinic, Barcelona, Spain. 26625jmc@comb.es
Echevarría
M
M
Gómez
O
O
Del Río
M
M
Borrell
A
A
Puerto
B
B
Fortuny
A
A
D000328:Adult; D001783:Blood Flow Velocity / Q000502:physiology; D002339:Carotid Arteries / Q000196:embryology / Q000502:physiology*; D005260:Female; D005865:Gestational Age; D006257:Head / Q000098:blood supply*; D006801:Humans; D007601:Jugular Veins / Q000196:embryology / Q000502:physiology*; D007621:Karyotyping; D008423:Maternal Age; D009333:Neck / Q000000981:diagnostic imaging / Q000196:embryology; D011247:Pregnancy; D011261:Pregnancy Trimester, First; D011446:Prospective Studies; D018615:Ultrasonography, Doppler, Color