Size of normal retroperitoneal lymph nodes.

The CT diagnosis of diseases in the retroperitoneal lymph nodes is based mainly on an evaluation of the size of the nodes in the transverse plane. Opinions on the normal size of the nodes vary, however. With the aim of obtaining a normal material, the diameters of the lymph nodes were measured on lymphograms that had been considered to be normal, from 95 patients. The upper limit for the diameter is not the same for all lymph nodes, but varies with the position of the node in the para-aortic chains, ranging from 7 to 15 mm, with increasing diameters in the caudal direction.