Additional renal veins: incidence and morphometry.

Modern surgical and radiological techniques dictate a reappraisal and definition of the renal venous anatomy. The purpose of this study was to investigate the incidence and morphometry of additional renal veins. One hundred fifty-three morphologically normal en bloc renal specimens were randomly selected from post-mortem examinations. Single additional renal veins were common on the right side (26%), while it was rare on the left side (2.6%). Second additional renal veins occurred infrequently on the right side (5%). Since additional renal veins may be encountered more than occasionally, it is worthwhile emphasizing their presence particularly to the transplant surgeon and the angiologist.