Fig. 3

Measurement of spinal canal cross-sectional area at different levels. The left and middle panels show sagittal and coronal views, with colored lines indicating the measurement planes (a-d). The right panel presents the corresponding axial CT slices, where the spinal canal cross-sectional area was manually delineated (green outline). (a) C6-7 level. (b) T2-3 level. (c) T9-10 level. (d) L2-3 level