umbilical vein varix
Umbilical vein varix (UVV) refers to a focal dilatation of the umbilical vein.
Epidemiology
Associations
UVVs were initially thought to have a high association with other anomalies which include:
- chromosomal anomalies: 5-12% with FIUVV
- underlying congenital cardiovascular anomaly
Recent literature points to more favorable outcomes when FIUVV is an isolated finding, with significantly lower associations with aneuploidy and mortality than initially reported .
Pathology
Location
It tends to favor the intra-abdominal portion of the cord (typically between the abdominal wall and the liver) which is then termed a fetal intra-abdominal umbilical vein varix (FIUVV) or the intra-amniotic portion of the umbilical vein.
Radiographic features
Ultrasound
Using antenatal ultrasound, an intra-abdominal UVV may be seen as a cyst-like structure in the fetal upper abdomen with venous flow within on color Doppler interrogation. The term umbilical varix is defined when the caliber is greater than 9 mm or with a ratio of more than 50% between the dilated and a more distal normal intra-abdominal portion of the vein.
Treatment and prognosis
The overall clinical course is variable and unpredictable ranging from favorable in some to unfavorable in others . Most cases with an isolated varix have a very good prognosis; most neonates will have a normal outcome.
Complications
- development of hydrops fetalis: ~5%
- due to thrombosis
- possibly from an associated cardiovascular anomaly
Differential diagnosis
Practical points
Due to its association with other fetal anomalies and relatively high mortality rates (when not an isolated finding), a careful fetal search for other abnormalities as well as close monitoring is recommended if detected prenatally. Follow-up is warranted when an umbilical vein varix is diagnosed (growth and well being), more so if other abnormalities are identified .
See also
Siehe auch:
- Hydrops fetalis
- umbilical arterial aneurysm
- congenital cardiovascular anomaly
- fetale intraabdominelle Zysten
- umbilical venous dilatation