Analysis of right‐sided ligamentum teres: The novel anatomical findings and classification

Abstract

Right-sided ligamentum teres (RSLT) is a rare congenital anomaly in which the fetal umbilical vein is connected to the right paramedian trunk. It was first described as left-sided gallbladder (LSGB) by Hochstetter et al. 1 This anomaly was initially thought to involve displacement of the gallbladder to the left side of the ligamentum teres (LT), but in 1997, Nagai et al 2 reported that LSGB resulted from anomalous attachment of the LT to the right paramedian trunk. Confusion regarding this anatomy persists due to the thought that the gallbladder position changed in patients with RSLT. A previous report proposed that LSGB occurred owing to ectopic gallbladder attachment to the left lobe of the liver, 3 whereas others suggested that sinistroposition of the gallbladder occurred due to developmental failure of the quadrate lobe. 4 The origin of this anomaly has not been fully explained but confusion has increased with a report of rightsided gallbladder in patients with RSLT. 5 Although we are likely to encounter patients with RSLT because it has an estimated prevalence of around 1%,

Laparoscopic Extended Left Lateral Sectionectomy for Hepatocellular Carcinoma in a Patient with Right-Sided Ligamentum Teres: A Case Report and Literature Review

“…Our patient exhibited an independent posterior branch of the portal venous system, which is present in more than half of patients with RSLT [1,2,5]. Shindoh et al classified RSLT into three types based on the portal branching pattern: bifurcation, trifurcation, and independent right lateral (posterior) type [1].…”

“…To the best of our knowledge, laparoscopic sectionectomy for a malignant liver tumor in a patient with RSLT has been reported only once previously [6]. Most patients with RSLT are treated using open surgery because of the high frequency of vascular and bile duct abnormalities [5]. However, the laparoscopic approach can be safe and effective with adequate preoperative and intraoperative imaging evaluations.…”

“…Shindoh et al classified RSLT into three types based on the portal branching pattern: bifurcation, trifurcation, and independent right lateral (posterior) type [1]. In contrast, Terasaki et al classified patients into four types: one bilateral ligamentum teres group and three RSLT groups (bifurcation, trifurcation, and independent posterior branch types) [5,7]. The newer Terasaki system may become the standard in the future.…”

“…However, a left-sided gallbladder associated with RSLT is actually an abnormality of the position of the ligamentum teres and should be distinguished from a "true" left-sided gallbladder, which is an abnormality of the position of the gallbladder itself [2,4]. Liver resection in patients with RSLT should be performed cautiously because this variant is associated with a high frequency of portal vein, hepatic vein, and bile duct abnormalities [5]. For this reason, most liver tumor patients with RSLT undergo open hepatectomy [6].…”

In‐utero evaluation of the fetal umbilical–portal venous system among fetuses with persistent right umbilical vein: Two‐and three‐dimensional ultrasonographic study

“…Our observation is consistent with this finding. In a recent large study by Terasaki et al, 24 computed tomography data of 76 patients with right‐sided Ligamnetum Teres were analyzed. Cases were classified into the four subtypes, accounted for the different types of main portal vein branching.…”