In pelvic surgery, it is important to anticipate potential anatomic variations, which may be unknown, and inter-relationships among intrapelvic vessels. Here, we comprehensively analyzed intrapelvic vessel patterns. This retrospective analysis included 81 patients that underwent colorectal surgery in our institution in 2016. A total of 162 half-pelvises were imaged with contrast-enhanced computed tomography. We scrutinized thin-slice images. We found variations in the number of internal iliac veins. In 47.5% of cases, one internal iliac vein drained into the ipsilateral common iliac vein in both halves of the pelvis. In the other cases, several internal iliac veins were observed in one or both halves of the pelvis. We analyzed the inter-relationships between the superior gluteal artery and the sacral nerve plexus in pelvic halves. Superior gluteal arteries ran between the 5th lumbar nerve and 1st sacral nerves, in 82% of halves, and lateral to the 5th lumbar nerve, in 17% of halves. Dorsally, the superior gluteal artery ran on the medial side of the internal iliac vein in 15% of halves. In 28% of half-pelvises, two superior gluteal veins were observed. Superior gluteal veins passed through the sacral nerve plexus lateral to 5th lumbar, between 5th lumbar and 1st sacral, and between 1st and 2nd sacral nerve, in 42.0, 47.5, and 37.7% of halves, respectively. We evaluated the rate of symmetric pelvic anatomies, and found that all anatomic variations formed symmetrically, except the number of internal iliac veins. This study clarified the anatomical variations of intrapelvic vessels and their inter-relationships. These findings will benefit our understanding of pelvic anatomy and enhance the safety of radical surgery for treating pelvic diseases.

中文翻译：

---

骨盆内血管的解剖变异分析，用于高级骨盆手术。

在骨盆手术中，重要的是要预见可能不知道的潜在解剖学变化，以及骨盆内血管之间的相互关系。在这里，我们全面分析了骨盆内血管的形态。这项回顾性分析包括2016年在我们机构进行了结直肠手术的81例患者。通过对比增强计算机断层扫描对总共162个半骨盆进行了成像。我们检查了薄片图像。我们发现内静脉的数量存在差异。在47.5％的病例中，一条内静脉排入骨盆两半的同侧common总静脉。在其他情况下，在骨盆的一个或两个半部中观察到了几条内静脉。我们分析了骨盆两半中臀上动脉和the神经丛之间的相互关系。臀上动脉介于第5腰神经和第1神经之间，占82％的一半，而在第5腰神经旁，占17％的一半。背臀上动脉位于15内静脉的内侧，约占一半。在28％的半骨盆中，观察到两条臀上静脉。臀上静脉穿过腰椎旁至第5腰，第5腰与第1 ac之间，第1和第2神经之间的the神经丛，分别占一半的42.0、47.5和37.7％。我们评估了对称的骨盆解剖的速率，发现除了内静脉的数目以外，所有解剖变异都是对称形成的。这项研究阐明了盆腔内血管的解剖变异及其相互关系。