Variability of origin of splanchnic and renal vessels from the thoracoabdominal aorta

Objective: To analyze the variability of origin of the celiac trunk (CT), the superior mesenteric artery (SMA), the right renal artery (RRA), and the left renal artery (LRA) in terms of mutual distances, angle from the sagittal aortic axis (clock position), and ostial diameters on computed tomography angiographies (CTAs) in three groups of patients. Methods: One hundred and fifty CTAs of 50 patients with a non-dilated thoracoabdominal aorta (group A), 50 with thoracoabdominal aneurysm (B), and 50 with infrarenal aneurysm (C) were reviewed. The measurements performed on CTAs, as well as the patients' age, sex, and body surface area, were analyzed. p values <.05 were considered statistically significant. Results: The clock position of the CT and the SMA, the diameters of all vessels, and the distance of the CT SMA followed a Gaussian distribution. In contrast, the clock position of the renal vessels did not follow a normal distribution, and nor did the distances of the SMA RRA, SMA LRA, RRA LRA or the distances between the renal arteries and the aortic bifurcation. The same values did not differ significantly among the three groups, with the exception of the distances between the renal arteries and the aortic bifurcation, significantly greater in group C. The clock position of the LRA and the distances of the SMA LRA, SMA RRA, RRA LRA and between both renal arteries and the aortic bifurcation showed a significant correlation with the increase of aortic diameter. Conclusion: The anatomic variability of the origin of both the CT and the SMA in terms of. clock position and mutual distances followed a Gaussian distribution, regardless of group. The same applies to the ostial diameters of renal and visceral vessels. In contrast, the origin of the renal vessels had a statistically significant heterogeneity that seemed to be correlated with the increase of aortic diameter in the mesenteric and renal aortic region.