[Endopyelotomy. Anatomical study of the vascular relationships to ureteropelvic junction].

In order to assist endourologists in performing endopyelotomy safely and efficiently, we have made an anatomical study on the vascular relationships to ureteropelvic junction (UPJ). Our material consisted of 82 3-dimensional polyester resin corrosion endocasts of pelviocaliceal system together with intrarenal arteries and 52 casts of pelviocaliceal system together with intrarenal veins. Relationships to renal arteries: in 53.6% of the cases (44/82 casts) we found a close relationship between the inferior segmental artery and the anterior surface of the UPJ (among these, in 1 case, there was 1 artery anterior and 1 artery posterior to UPJ). In the other cases (38/82 casts), the UPJ was not related to arteries. Relationships to renal veins: in 40.4% of the cases (21/52 casts) we found a close relationship between an important tributary of the renal vein and the anterior aspect of the UPJ (among these, in 1 one case, existed 1 vein anterior and 1 vein posterior to UPJ). In the other cases (31/52 casts), the UPJ was not related to veins. Due to our findings, we can advise that UPJ must be incised just laterally, avoiding arteries and veins.