Liang KW, et al. Korean J Radiol. 2025 Mar;26(3):230-238. https://doi.org/10.3348/kjr.2024.0883

Right-sided ligamentum teres (RSLT) hepatis is a rare anatomical variant in which the fetal umbilical vein is connected to the right paramedian trunk of the portal vein. Despite its rarity, it is crucial for surgeons and intervention specialists because of its frequent association with intrahepatic vascular and biliary anomalies. Inattention to these anomalies before intervention, especially living-donor liver transplantation, can have life-threatening consequences. The relationship between gallbladder location and RSLT is still controversial, with RSLT regarded as one of the critical features of left-sided gallbladder in most studies. According to these hypotheses, once RSLT is present, left-sided gallbladder must be found as well. Here, we report three cases in which RSLT was associated with intrahepatic portal vein anomalies. In one case, the gallbladder was left-sided, but in the other two cases, it had a normal cholecystic axis to the right of the umbilical fissure. Therefore, the relationship between RSLT and gallbladder location may require redefinition, and surgeons should be aware of vascular anomalies once RSLT has been detected, even in the absence of left-sided gallbladder or biliary anomalies.

Right-sided ligamentum teres (RSLT) is often associated with portal venous anomalies (PVA) and is regarded as a concerning feature for hepatobiliary intervention. Most studies consider RSLT to be one of the causes of left-sided gallbladder (LGB), leading to the hypothesis that LGB must always be present with RSLT. However, some cases have shown that right-sided gallbladder (RGB) can also be present in livers with RSLT. To highlight the rare variation that RSLT may not come with LGB and to determine whether ligamentum teres (LT) or gallbladder location is reliable to predict PVA. This study retrospectively assessed 8552 contrast-enhanced abdominal computed tomography examinations from 2018 to 2021 [4483 men, 4069 women; mean age, 59.5 ± 16.2 (SD) years]. We defined the surrogate outcome as major PVAs. The cases were divided into 4 subgroups according to gallbladder and LT locations. On one hand, we analyzed PVA prevalence by LT locations using gallbladder location as a controlled variable (n = 36). On the other hand, we controlled LT location and computed PVA prevalence by gallbladder locations (n = 34). Finally, we investigated LT location as an independent factor of PVA by using propensity score matching (PSM) and inverse probability of treatment weighting (IPTW). We found 9 cases of RSLT present with RGB. Among the LGB cases, RSLT is associated with significantly higher PVA prevalence than typical LT [80.0% vs 18.2%, P = 0.001; OR = 18, 95% confidence interval (CI): 2.92-110.96]. When RSLT is present, we found no statistically significant difference in PVA prevalence for RGB and LGB cases (88.9 % vs 80.0%, P > 0.99). Both PSM and IPTW yielded balanced cohorts in demographics and gallbladder locations. The RSLT group had a significantly higher PVA prevalence after adjusted by PSM (77.3% vs 4.5%, P < 0.001; OR = 16.27, 95%CI: 2.25-117.53) and IPTW (82.5% vs 4.7%, P < 0.001). RSLT doesn't consistently coexist with LGB. RSLT can predict PVA independently while the gallbladder location does not serve as a sufficient predictor.