Morphological assessments on the arteries of the superior renal segment.

The study was performed on 461 renal arteries in order to assess some morphological aspects regarding the arteries that supply the superior renal segment using as study methods: dissection, injection of contrast medium, injection of plastic followed by corrosion together with the examination of MRI and renal angiographies (simple and angio CT). The posterior arteries of the superior renal segment originate mostly from the posterior terminal branch of the renal artery as 1-3 arterial branches. In only 42 cases, we found posterior branches that do not participate in the supply of the superior renal pole. In 190 cases, the anterior arteries of the superior segment originated from the anterior division of the renal artery and in 73 cases directly from the trunk of the renal artery. 34 cases were assessed as a terminal division of the renal artery, while the origin from the posterior division of the renal artery was encountered in 18 cases. In 138 cases, the artery of the superior segment originated from a supplementary renal artery, double (118 cases) or triple (20 cases); in this situation, from the polar artery started the inferior suprarenal artery, except five cases where it originated from the aorta. Of the total of 461 samples, in 244 cases the renal approach was performed above the renal hilum, as proper superior polar arteries and in 217 cases the artery entered through the upper part of the hilum as an apical artery. The morphology of the arteries of the superior renal segment shows a significant degree of variability mostly in what concerns the anterior ones. Frequently we encountered a clear delimitation of the superior renal segment (in 61% of the cases), a situation that allows a relatively facile nephrectomy.

The morphology and the surgical importance of the gonadal arteries originating from the renal artery.

Using dissection and plastic injection followed by corrosion as study methods, we describe 16 cases of gonadal arteries originating from the renal artery. Among them, in 12 cases (75%), we assessed this variation on a single gonadal artery while two gonadal arteries appeared in four cases (25%). In 13 cases (81.25%) the gonadal arteries were located on the left side and in only three cases (18.75%) they were on the right. In seven cases (43.75%), a unique gonadal artery that originated from a single renal artery, in three cases (18.75%) the gonadal artery started from the artery of the inferior segment that started from the anterior branch of the renal artery, in other three cases (18.75%), from the trunk of the renal artery, prior to its terminal ramification and in one case (6.25%), from the artery of the superior segment that started from the anterior branch of the renal artery. In five cases (31.25%), a single gonadal artery started from a supplementary renal artery, in four cases (25%), from double renal arteries (three from the inferior and one from the superior one) and in a single case, from triple renal arteries (from the inferior one). All the four cases (25%) of double gonadal arteries were located on the left. Within them, in two cases, the two gonadal arteries started from the renal artery (unique or supplementary) and in the other two cases, the lateral gonadal artery originated from the renal artery (unique or supplementary) and the medial one from the aorta. This vascular variation shows a significant importance for renal surgery, in partial or total nephrectomy or in the renal transplant as long as it may lead to the compromise of the gonadal blood supply, mostly when the gonadal artery with renal origin is unique, without a second one with aortic or other arterial origin. A gonadal artery with origin from an inferior polar renal artery may be injured during the percutaneous treatment of the syndrome of pielo-ureteral junction, so it becomes a major contraindication. Also, this anatomical variation enhances the importance of the arteriography or Doppler ultrasound examination of the renal hylum. Sometimes, the gonadal artery may pass posterior to the proximal ureter that can be disturbed in traject, leading to hydronephrosis.