Newly found variations of the right posterior portal vein identified radiologically in 1,003 Chinese patients: a cross-sectional study

BACKGROUND: The anatomy of the right posterior portal vein (RPPV) plays an important role in planning hepatic resection, living transplantation and interventional radiological procedures, yet the incidence of variations of RPPV without a common trunk in Chinese persons is still unclear. Therefore, we conducted this study and discussed its clinical implications. METHODS: A retrospective analysis of multidetector computed tomography (MDCT) scans was performed in 1,933 patients with various abdominal pathologies between September 28, 2018 through May 23, 2019. After excluding 930 patients, a total of 1,003 patients were included in this study. Variations of the RPPV without a common trunk were classified according to classification standards. RESULTS: A total of 1,003 patients were included. RPPV without a common trunk was found in 216 (21.54%, 216/1,003) patients. Among them, we identified three variations of the origin from the right portal vein (RPV): first separate origin of P6, P7, or simultaneous separate origin of P6 and P7, and the incidences of these three variations were 1.50% (15/1,003), 6.58% (66/1,003) and 13.46% (135/1,003), respectively. Among 1,003 patients included in this study, 787 patients (78.46%, 787/1,003) showed that RPPV normally divided into P6 and P7 branches. CONCLUSIONS: Variations of the RPPV without a common trunk were not rare in Chinese population. Knowledge of this anatomic variation of the RPPV is extremely important for hepatic and transplant surgeons and interventional radiologists.