[Morphology and anatomical variations of the left gastric vein].

摘要

Objective: To explore the gross morphology and variation characteristics of the left gastric vein (LGV) by means of cadaveric anatomical measurement and three-dimensional imaging reconstruction. Methods: A total of 39 adult cadaver specimens fixed with 4% formaldehyde solution from Zhongshan School of Medicine, Sun Yat-sen University, and 40 cases of abdominal contrast-enhanced CT imaging data of patients with gastric cancer admitted to the Seventh Affiliated Hospital of Sun Yat-sen University between January 2023 and December 2024 were included in this study. Specimens with obvious decomposition, tissue deformation, structural damage, or a history of upper abdominal surgery were excluded; patients with pathologically confirmed gastric cancer and CT images suitable for three-dimensional vascular reconstruction were selected, while those complicated with liver cirrhosis, portal hypertension, or a history of major upper abdominal surgery were excluded. The perigastric and perihepatic vessels were exposed in cadaver specimens to observe the morphology and course of the LGV and measure related anatomical parameters; the imaging data were scanned with dual-source CT using standardized parameters, and three-dimensional vascular reconstruction was performed on a post-processing workstation. The LGV was classified according to the Lee criteria. Results: Cadaveric dissection showed that the LGV originated from the middle of the lesser curvature of the stomach, coursed leftward along the lesser curvature, received 2-3 esophageal veins at the inferior margin of the esophageal hiatus, and then obliquely descended rightward to drain into the hepatic portal vein. Both cadaveric dissection and imaging detected three drainage sites of the LGV: the hepatic portal vein, the portal vein angle, and the splenic vein. CT angiography (coronal plane) and cadaver specimens both showed that the proportion of drainage into the hepatic portal vein was the highest [52.5% (21/40) vs. 53.8% (21/39)], followed by the splenic vein [35.0% (14/40) vs. 41.0% (16/ 39)], and the least common was drainage into the portal vein angle [12.5% (5/40) vs. 5.1% (2/39)]. The length of the LGV was (40.3±7.4) mm in cadaver specimens and (48.4±11.9) mm on imaging; the distance from the drainage site to the portal vein angle was (13.8±8.1) mm in cadaver specimens and (13.1±8.2) mm on imaging. In both the imaging group and the cadaver group, the type Ip accounted for the highest proportion of LGV classification, at 40.0% (16/40) and 41.0% (16/39), respectively, and no type IV was detected in either group. The proportion of type II in the imaging group was 22.5% (9/40), which was higher than that in the cadaver group (7.7%, 3/39); the proportion of type Ia in the cadaver group was 25.6% (10/39), which was higher than that in the imaging group (15.0%, 6/40); the proportions of type IIIa (20.0% in the imaging group vs. 20.5% in the cadaver group) and type IIIp (2.5% in the imaging group vs. 5.1% in the cadaver group) were similar between the two groups. Conclusions: There are certain variations in the anatomical course and diameter of the LGV. The LGV most commonly drains into the hepatic portal vein, and is mainly classified as type I. 目的： 采用尸体解剖学测量与影像学三维重建的方法，探究胃左静脉大体形态和变异特点。 方法： 本研究纳入中山大学中山医学院的39具经4%甲醛溶液固定的成人尸体标本以及中山大学附属第七医院于2023年1月至2024年12月期间收治的40例胃癌患者腹部增强CT影像资料。标本排除腐败变形、结构损毁及有上腹部手术史者；患者选取病理确诊胃癌、CT图像可完成血管三维重建病例，排除合并肝硬化、门静脉高压及上腹部重大手术史者。对尸体标本解剖暴露胃周及肝周血管，观察胃左静脉形态走行并测量相关解剖参数；影像学资料采用双源CT规范参数扫描，经后处理工作站行血管三维重建。参照Lee标准对胃左静脉进行分型。 结果： 尸体标本解剖显示，胃左静脉始于胃小弯中部，沿胃小弯左行，于食管裂孔下缘收纳2~3条食管静脉，继而向下斜行向右汇入肝门静脉。尸体解剖和影像学均测得胃左静脉汇入点位置有：肝门静脉、门静脉角、脾静脉。CT血管影像（冠状面）和尸体标本均显示，汇入肝门静脉的比例最高［分别为：52.5%（21/40）、53.8%（21/39）］，其次是脾静脉［分别为：35.0%（14/40）、41.0%（16/39）］，最少汇入到门静脉角［分别为：12.5%（5/40）、5.1%（2/39）］。胃左静脉的尸体标本长度（40.3±7.4）mm，影像学为（48.4±11.9）mm，汇入点与门静脉角距离（13.8±8.1）mm，影像学为（13.1±8.2）mm。影像组与尸体标本组胃左静脉（胃左静脉）分型均以Ⅰp型占比最高，分别为40.0%（16/40）与41.0%（16/39），且均未检出Ⅳ型。影像组中Ⅱ型占比为22.5%（9/40），高于标本组的7.7%（3/39）；而Ⅰa型占比在标本组为25.6%（10/39），高于影像组的15.0%（6/40）；两组间Ⅲa型（影像组20.0%、标本组20.5%）与Ⅲp型（影像组2.5%、标本组5.1%）占比相近。 结论： 胃左静脉解剖走行及管径存在一定变异，胃左静脉汇入肝门静脉比例最高，分型以Ⅰ型为主。.