Right gonadal arteries passing dorsally to the inferior vena cava: embryological hypotheses

Abstract

The right gonadal artery (RGA) usually arises from the anterior wall of the abdominal aorta below the level of the renal arteries and veins, passes ventrally to the inferior vena cava (IVC), and then runs obliquely downward to reach the pelvic cavity. In this study, we observed 59 Japanese cadavers and found that in eight of them (13.6%), the RGA's passed dorsally to the IVC. Together with the various courses of RGAs reported in the literature, we here divided the courses into four subtypes, due to the relationship to the left renal vein and the IVC, of superior, middle and lower types (L1 = ventrally, L2 = dorsal of IVC). Superior type was seen in 3.6%. Lower types were fount to in the most cases (L1: 83.5%, L2: 13.6%). The middle type was not realized. The classification of this variations make it easy to describe the RGA's passing below the level of the left renal vein. RGA can pass either ventrally or dorsally to the IVC. RGAs passing at or above the level of the left renal vein run dorsally but not ventrally to the IVC. The variations in the origin, course and branching of RGAs are attributed to development of the IVC.

Variations in the gonadal artery with a single common trunk: embryological hypotheses by observation

“…In general, the variations in the origin, course, and branching out of the right GAs are attributed to the development of the IVC. Only Terayama et al [18] reported on the development of the RTA and IVC system together. Several successive networks participate in the formation of the IVC through the initial appearance of complex capillary plexuses and preferential utilisation and expansion or regression of individual channels within the plexus [2,18].…”

“…Only Terayama et al [18] reported on the development of the RTA and IVC system together. Several successive networks participate in the formation of the IVC through the initial appearance of complex capillary plexuses and preferential utilisation and expansion or regression of individual channels within the plexus [2,18]. The sub-cardinal veins arise in association with the ventral margin of the mesonephros and form the sub-cardinal anastomosis, which is the origin of the gonadal and renal veins [4,18].…”

“…Several successive networks participate in the formation of the IVC through the initial appearance of complex capillary plexuses and preferential utilisation and expansion or regression of individual channels within the plexus [2,18]. The sub-cardinal veins arise in association with the ventral margin of the mesonephros and form the sub-cardinal anastomosis, which is the origin of the gonadal and renal veins [4,18]. Thereafter, the supracardinal veins appear dorsal to the sub-cardinal veins, and the supracardinal and sub-cardinal veins anastomose (Fig.…”

Bilateral variations of the testicular vessels: Embryological background and clinical implications

“…This type of right testicular artery was reported in 1 case, [9,16] in 0.8% cases [17] and in 0% (0/59) cases. [18] The retrocaval passage of the right testicular artery can also be explained in terms of embryology. Testicular arteries represent persistent lateral splanchnic branches of dorsal aorta that enter the mesonephros, crossing ventral to the supracardinal vein and dorsal to subcardinal vein.…”

Multi-Acupuncture Point Injections and Their Anatomical Study in Relation to Neck and Shoulder Pain Syndrome (So-Called Katakori) in Japan

“…1758: 78 years old, colon cancer; NO. 1781: 73 years old, gastric cancer) from the anatomy laboratory of the Tokai University School of Medicine (from the Association of Tokai University donations), Japan, during routine educational dissections carried out in 2013 [ 20 – 23 ]. The needles used for acupuncture point injections were 25 gauge.…”