Fig. 1.

Manual measurement of the cortical diameter and segmentation of all visible LNs in axillary level I. A 49-year-old woman diagnosed with invasive ductal carcinoma underwent preoperative MRI, including high-resolution 3D T2-weighted imaging. The LN with the largest cortical diameter was selected to manually measure the cortical diameter (a). Manual 3D segmentation of all visible LNs in axillary level I was performed using ITK-SNAP (b–f), and the 3D volumes of interest for all visible LNs were obtained to extract the texture features. Six LNs were identified on 3D rendering from the coronal view (g). In this case, the manual measurement of cortical diameter was 6.41 mm. The volume of all LNs was 1359 mm³, and the texture-volume model indicated positive LN metastasis. The case was diagnosed as sentinel LN metastasis with a 1.5 mm metastatic nest by sentinel LN biopsy. LN, lymph node.