Anatomic variation in the origin of the main renal arteries: spiral CTA evaluation

The aim of this study was provide quantitative data on the origin and traje ctory of the main renal arteries using spiral CT angiography and arteriogra phy, Normal renal artery anatomy was assessed on spiral CT angiography (axi al transverse-sections and shaded-surface-display reconstructions) in 100 p atients referred for renal arteriography who had no significant renal arter y stenosis. Two hundred major renal arteries were studied. The vast majorit y of right (88%) and left (87%) renal arteries originated between the lower third of the first lumbar vertebra and the-lower borde of the second lumba r vertebra. In 50 patients both ostia were at the same level; in the remain ing 50 patients, the right ostium was located above the left in 37 patients . On the right, the angle of origin varied from -10 to +55 degrees (mean 24 degrees). On the left, the angle of the origin varied from +30 to -55 de grees (mean -11 degrees). Spiral CT angiography provides additional anatomi c data, notably regarding the angle of origin of the renal arteries, that i s potentially useful. for planning interventional procedures.