A prospective radiological anatomical study of the variations of the position of the colon in the left pararenal space

Percutaneous puncture of the kidney allows direct access to the pyelocalici al cavities. The posterior approach of this retroperitoneal organ can be co mplicated of transcolic punctures due to the postrenal position of the colo n. A prospective radiological anatomical study of the relationship between the left kidney and the descending colon was undertaken. One hundred comput ed tomograms of adult subjects were obtained from which the anatomy of the left perirenal area was determined: the descending colon is more frequently behind the kidney in the young females. Two main factors determinants of t his situation are: 1) colon ontogenesis in relation to the attachment of th e primitive mesocolon, permitting a 'fixed' left colon, or 'moving' left co lon at the end of a long mesocolon, allowing it to pass behind the kidney; 2) a mechanical factor whereby the accumulation of perirenal fat with incre asing age may be a limiting factor in lateral displacement of the colon.