FIG 1. CT scans obtained from patient 2, a 52-year-old woman.

A, Coronal multiplanar reconstruction scan shows the ASA along the anterior midsagittal surface of the spinal cord (small white arrows). The large radiculomedullary artery (black arrow), which is defined as the AKA, arises from the left T10 level and joins the ASA. Both the ascending and descending branches of the ASA distal to the junction with the AKA are seen, but the ascending branch is narrower than the descending branch. The spinal branch (curved white arrow) arises from the left 10th intercostal artery (large white arrow).

B, On the dorsal section of the coronal view, the continuity of the radiculomedullary artery and intercostal artery (large white arrow) via the spinal branch (curved white arrow) is confirmed.

C and D, Axial scans show the ASA (small white arrows) and AKA (black arrows) in the dural sac. The continuity of the intercostal artery (large white arrow), spinal branch (curved white arrows), and radiculomedullary artery (black arrows) is also seen.

E, Curved multiplanar reconstruction scan allows the visualization of the continuity of the intercostal artery (large white arrow), spinal branch (curved white arrow), radiculomedullary artery (black arrow), and ASA (small white arrows) on a single section. The change of caliber of these vessels is also seen.