GROUPS OF PELVIC LYMPH-NODES IN COMPUTED- TOMOGRAPHY - TOPOGRAPHIC ATLAS

This atlas was prepared to facilitate the diagnosis of lymph mode enla rgement in the pelvic region and to improve topographic diagnosis. Fif ty computed tomographies were performed after lymphography using centi metric pelvic slices in order to select eight levels for reference. A statistical analysis was conducted to establish a diagram of the mean number of lymph nodes on the right and left side for each level. A tab le was established indicating the mean number and standard deviation f or each group of nodes for the 8 different levels. In addition, a cont rol slice (chosen among 50) accounts for the morphology of the iliac v essels, of the lymph nodes and psoas muscle most frequently encountere d at each level. The distribution of the groups of nodes shows why int erpretation can be difficult, particularly at vessel bifucations and c onfluents. Precise morphology based on effective opacification, especi ally in the pelvic area, is required for positive and especially topog raphic diagnosis. Finally, the description of the medial border of the psoas muscle and its close relations with certain groups of lymph nod es can cause some problems because of the similar densities. The atlas is of great help here.