Size of Normal Hilar Lymph Nodes Measured in Autopsy Specimens

The normal size of lymph nodes for each region of the hilum was determined by direct measurement of the short and long diameters of each node in the transverse plane of the node and the longitudinal diameter in the vertical plane of the node in 30 adult cadavers. The mean short transverse diameters ranged from 3.2 to 6.4 mm, the mean long transverse diameters ranged from 4.9 to 10.0 mm, and the mean longitudinal diameters ranged from 5.7 to 11.3 mm. The largest mean transverse diameters were found in the anterior upper lobe (AUL) and the inferior interlobar (IIL) regions. We noted a different maximum normal size for lymph nodes in each region of the hilum and determined the standard maximum normal short transverse diameters to be as follows: 12 mm for nodes in the right AUL and IIL regions, 10 mm for nodes in the right superior interlobar region and the left AUL and IIL regions, and 8 mm for nodes in other regions. Both the maximum normal long transverse diameters and the longitudinal diameters showed a wider variation, ranging from 18 to 10 mm and from 20 to 12 mm, respectively.