[Retroperitoneal pathology].

The retroperitoneum is one of the most complex regions of human anatomy as it contains a variety organs and structures from different systems, in particular those belonging to the urinary and digestive tracts and the vascular systems. The emergence of different diagnostic imaging techniques has made easier to study the retroperitoneum. Thanks to ultrasonography, computerised tomography and magnetic resonance the assessment of retroperitoneal conditions has taken a great leap forwards permitting the anatomical connections and characteristics of the structures in this region to be reliably established. Owing to the location in the retroperitoneal space of the different organs of the digestive tract and the vascular system, a multidisciplinary approach is required involving the different surgical specialties. The urologist performs a large proportion of his surgical activity in this region and must, therefore, have a good knowledge of the different retroperitoneal organs belonging to the urinary tract and also the connections between these and other organs and structures of the retroperitoneal region.