Anatomy of the nerves and ganglia of the aortic plexus in males

Abstract

It is well accepted that the aortic plexus is a network of pre-and post-ganglionic nerves overlying the abdominal aorta, which is primarily involved with the sympathetic innervation to the mesenteric, pelvic and urogenital organs. Because a comprehensive anatomical description of the aortic plexus and its connections with adjacent plexuses are lacking, these delicate structures are prone to unintended damage during abdominal surgeries. Through dissection of fresh, frozen human cadavers (n = 7), the present study aimed to provide the first complete mapping of the nerves and ganglia of the aortic plexus in males. Using standard histochemical procedures, ganglia of the aortic plexus were verified through microscopic analysis using haematoxylin & eosin (H&E) and anti-tyrosine hydroxylase stains. All specimens exhibited four distinct sympathetic ganglia within the aortic plexus: the right and left spermatic ganglia, the inferior mesenteric ganglion and one previously unidentified ganglion, which has been named the prehypogastric ganglion by the authors. The spermatic ganglia were consistently supplied by the L1 lumbar splanchnic nerves and the inferior mesenteric ganglion and the newly characterized prehypogastric ganglion were supplied by the left and right L2 lumbar splanchnic nerves, respectively. Additionally, our examination revealed the aortic plexus does have potential for variation, primarily in the possibility of exhibiting accessory splanchnic nerves. Clinically, our results could have significant implications for preserving fertility in men as well as sympathetic function to the hindgut and pelvis during retroperitoneal surgeries.

Retroperitoneal Lymph Node Dissection: Anatomical and Technical Considerations from a Cadaveric Study

“…4). Following the right LSNs anteriorly will reveal the right cord of the aortic plexus, a longitudinal nerve running along the antero-medial aspect of the infrarenal abdominal aorta which contributes to the formation of the superior hypogastric plexus [21]. With the right-sided nerves spared, the preaortic nodes can be split, with care to preserve any preaortic nerves that may connect with the contralateral cord of the aortic plexus.…”

“…While the aortic plexus is usually bilaterally symmetric in its organization [21], it should be appreciated that it rarely exhibits a bilateral symmetric position . Thus, the position of the right LSNs cannot be used to landmark the left LSNs.…”

“…1). Note that retroaortic LSNs will course between the left common iliac artery and vein to join the superior hypogastric plexus directly [21]. …”

“…Studies have also described the anatomy of the sympathetic nerves comprising the aortic plexus. Specifically, it has been shown that the aortic plexus is supplied by at least two lumbar splanchnic nerves (LSN) 1 on each side and is composed of two parallel nerves (cords), each containing two major ganglia [21]. Collectively, these studies provide a strong foundation for understanding the retroperitoneal neurovascular anatomy.…”

Histological verification of the prehypogastric and ovarian ganglia confirms a bilaterally symmetrical organization of the ganglia comprising the aortic plexus in female human cadavers

“…Motivated by this, our group recently published the first detailed anatomical description of the aortic plexus and its ganglia in human males through dissection, followed by a histological examination of fresh frozen cadavers (Beveridge et al. ). Importantly, our study characterized the prehypogastric ganglion, a novel structure which we suggested could be the right‐sided equivalent of the well‐acknowledged inferior mesenteric ganglion.…”