Size of noncancerous hilomediastinal lymph nodes measured on coronal and sagittal reconstruction CT images

To determine the sizes of hilomediastinal lymph nodes on coronal and sagittal reconstruction computed tomographic images of subjects without known malignancies. We evaluated 560 lymph nodes of 246 consecutive patients who underwent multidetector-row computed tomography (MDCT) of the chest, then reconstructed coronal and sagittal images on a viewer and measured short-axis diameters of lymph nodes in each station according to the American Thoracic Society (ATS) map for axial, coronal, and sagittal images. On coronal images, short-axis diameters were signifi cantly larger than on axial images in station #4R (P < 0.01). On sagittal images, short-axis diameters were signifi cantly smaller than on axial images in stations #4L (P < 0.01), #10R (P < 0.001), and #10L (P < 0.05). On coronal and sagittal images, short-axis diameters were signifi cantly smaller than on axial images in stations #11R (P < 0.001). In #7, diameters were signifi cantly larger on coronal images than on axial and sagittal images (P < 0.001), and diameters were signifi cantly smaller on sagittal images than on axial images (P < 0.01). In stations #4R, #4L, #7, #10R, #10L, and #11R, measurements of short-axis diameters of hilomediastinal lymph nodes differed on coronal and sagittal images. On coronal and sagittal images, evaluation of hilomediastinal lymph nodes requires unique size criteria for every station.