[Up-to-date computed tomographic findings on the para- and perirenal spaces under normal and pathologic conditions].

The anatomy of the peri- and pararenal spaces was critically reviewed, supported by high-definition CT images. In the past, CT did not allow the visualization of such structures as the perirenal septa. Nowadays, on the contrary, such anatomical structures can be demonstrated, which allows their involvement to be monitored in pathologic conditions. The perirenal septa appear thus to prevent fluid collections from spreading, while they seem to be the preferential pathways for the diffusion of malignant lesions.