1Division of Gastroenterology, Toranomon Hospital, 2Division of Radiology, Toranomon Hospital, 3Division of Clinical Physiology, Toranomon Hospital, 4Department of Surgery, Hiratsuka Gastrointestinal Hospital
Ultrasonography, Anomaly of the umbilical portion of the portal vein, Preduodenal portal vein, Azygos continuation of inferior vena cava, Polysplenia syndrome
Sonographic findings of multiple developmental anomalies, including preduodenal portal vein,
azygos continuation of the inferior vena cava, left-sided gallbladder and polysplenia, demonstrated
in an asymptomatic 30-year-old male are reported.
In addition to the preduodenal portal vein, anomalous positioning of the umbilical portion (UP)
of the portal vein (PV) was also noted.
The anomalous UP was formed by the base of the right anterior segmental branch of the portal
vein (PV), while the normal UP in the left hepatic lobe was absent. The round ligament was found
on sonography to originate from the top of the anomalous UP.
We have named this anomalous UP of the PV "right-sided UP".