北村 隆信^{1, 4}, 竹内 和男¹, 村島 直哉¹, 橋本 光代¹, 吉田 行哉¹, 中島 正男¹, 黒崎 敦子², 桑山 美知子³

Takanobu KITAMURA^{1, 4}, Kazuo TAKEUCHI¹, Naoya MURASHIMA¹, Mitsuyo HASHIMOTO¹, Yukiya YOSHIDA¹, Masao NAKAJIMA¹, Atsuko KUROSAKI², Michiko KUWAYAMA³

¹虎の門病院消化器科, ²虎の門病院放射線診断学科, ³虎の門病院臨床生理検査室, ⁴平塚胃腸病院外科

¹Division of Gastroenterology, Toranomon Hospital, ²Division of Radiology, Toranomon Hospital, ³Division of Clinical Physiology, Toranomon Hospital, ⁴Department of Surgery, Hiratsuka Gastrointestinal Hospital

キーワード : 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".