Systematic Review and Meta‐analysis of the Anatomical Variants in Renal Vascularization and their Clinical Implication using Anatomical Quality Assurance (AQUA) checklist
Authors: Matta Josefa I. , Beas Antonia , Benitez Javiera , Orellana Mathias , Santana Andres , Valenzuela Juan J. 
Published: May 2022

Introduction

Anatomically, the vascularization and venous drainage of the kidney is provided by the renal artery and vein. Generally, the kidney consists of a renal artery originating in the abdominal aorta, which later divides into an anterior and posterior branch, however it is not uncommon to find more than one emerging from the abdominal part of the aorta, in addition to some iliac artery or rarely originating from the lower thoracic aorta or mesenteric arteries. On the other hand, the renal veins drain on the inferior vena cava, but the left renal vein a longer course, crossing the midline anterior to the abdominal aorta and posterior to the superior mesenteric artery.

Materials and methods

We considered specific scientific articles and books of human anatomy, written in Spanish or English, published between 2000 and 2021. The search process was carried out in the following databases: MEDLINE, SCIELO, WOS, CINHAL, SCOPUS and GOOGLE SCHOLAR, using as search terms “renal artery ”, “anatomical variation”, “renal veins”, “” and “renal vascularization” for which the following Boolean connectors “AND”, “OR” and “NOT” were used, also to see the bias was used The Anatomical Quality Assurance (AQUA) checklist.

Results

Regarding the incidence of the variants in renal vascularization, these are reported as follows; variants only of the renal artery, variants only of the renal vein and finally variants of both the artery and the renal vein. For the variants of the origin of the renal artery, four studies with an N greater than 1 in their sample, reported variation in the origin of the renal artery where this artery has two branches that originate from the aorta artery, one that is polar superior or lower and the other is directed towards the renal hilum. In these studies, the incidence varied between 16.66% and 31% with a mean of 25.54% and a cumulative n of 1594 patients. For the variant of the origin of Renal artery in studies with N equal to 1, three studies were presented, of which two presented an accessory inferior polar artery, while one study presented origin of the renal artery at the level of the thoracic aorta. Regarding the incidence of variation in the trajectory of the renal artery, eight studies were found, which reported variations in the trajectory of the renal artery, which were mainly multiple renal arteries that bifurcated laterally to their origin in the abdominal aorta artery. While one study showed multiple renal artery surrounding the abdominal aorta artery, the incidence of these variations fluctuated between 6.7% and 100% with a mean of 62.45% with a total accumulated N of 879 in the sample of the included studies.

Conclusions

The amount of variations in renal vascularization is very wide, so the knowledge of professionals who treat pathological conditions of the abdominal region becomes crucial, since ignoring these variations could lead to complications in the surgical approach or in the diagnosis. We also believe that future studies that associate these variations with some pathologies would also be important.