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

Objective: To determine the sizes of hilomediastinal lymph nodes on coronal and sagittal reconstruction computed tomographic images of subjects without known malignancies.

Methods: 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.

Results: On coronal images, short-axis diameters were significantly larger than on axial images in station #4R (P < 0.01). On sagittal images, short-axis diameters were significantly 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 significantly smaller than on axial images in stations #11R (P < 0.001). In #7, diameters were significantly larger on coronal images than on axial and sagittal images (P < 0.001), and diameters were significantly smaller on sagittal images than on axial images (P < 0.01).

Conclusions: 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.