Fig. 2

Measurement of the distance between the tracheostoma and brachiocephalic artery (TB length) using straight lines; the orange dot line passed from the tracheostoma to the anterior part of the trachea, while the red dot line passed from the trachea along the tracheal tube. A representative case is shown in A (case 2 in the LTS group) and B (Case 21 in the GC group). When the tracheostomy tube tract was not traced in one sagittal image because of deformity of the trachea in a patient with severe scoliosis (C, case 15 in the GC group), the axial image was reconstructed to measure the TB length in one image (D). The arrowhead indicates the brachiocephalic artery